Hand features the engine instead of guessing it from a viewer

No code outside src/globe calls isGlobeEngine or engineFromViewer any more (14 calls left before this). The features that still sniffed take the engine from their caller: - Projection and surface helpers (focus de-emphasis, icon orientation, ground snap, the mesh floor sampler, ground picks) take the engine; the engine view's scene carries its projector instead of registering itself as a viewer. - Credits go only through engine.credits, so annotations and layers share one OSM credit state on Cesium too (it could show twice). - The annotation board and the resolver work on the engine: camera assists, visibility and picks go through engine.camera, engine.projector and src/geo, without Cesium. - The Recent Imagery box tool has one implementation for both engines, on capture-phase canvas pointer events with the layer's engine.ground preview; the Navara copy goes. On Cesium the preview outline is solid now, as on Navara. - Scene interactions take the engine, and the render governor has an engine variant beside the Cesium one. Remaining engine-specific features stay behind explicit seams until the contract covers them: the draw tool's Cesium surface (stock click actions cannot be suspended), the annotation drapes (animated materials), share follow, Cesium post effects and cyber sonar, and data packs (meshes). Coupling: Cesium-importing files fall from 31 to 27, `viewer` lines from 1367 to 1234, engine sniffing calls from 14 to 0.
2026-11-09 21:02:19 +00:00 · 2026-11-07 08:46:30 +04:00
1 parent 406dd9122e
commit f1ec9d4a22
@@ -2,15 +2,15 @@
  "metrics": {
    "cesiumLayerRendererLines": 330,
    "navaraLayerRendererLines": 2304,
-    "cesiumImportFiles": 31,
-    "viewerLines": 1367,
-    "navaraKindChecks": 6,
-    "engineSniffCalls": 14,
+    "cesiumImportFiles": 27,
+    "viewerLines": 1234,
+    "navaraKindChecks": 5,
+    "engineSniffCalls": 0,
    "engineExtensionReads": 12,
    "groundEffectPasses": 3,
    "cesiumSdkLoads": 4,
    "screenSpaceHandlerFiles": 4,
-    "engineNameLines": 78
+    "engineNameLines": 73
  },
-  "measuredAt": "after engine.imagery with FIRMS heat and Recent Imagery on it, 2026-11-07"
+  "measuredAt": "after the phase 7 feature moves, 2026-11-07"
 }
@@ -1401,7 +1401,6 @@
  "scripts/fixtures/w2/radio.mjs",
  "scripts/qa-map-policy.mjs",
  "scripts/qa-map-policy.test.mjs",
-  "src/ui/imageryBoxNavara.test.mjs",
  "scripts/qa-w2-imagery.mjs",
  "src/globe/navara/postSamplingPass.test.mjs",
  "src/globe/navara/emptySceneRender.test.mjs",
@@ -3415,7 +3415,6 @@
      "src/layers/vessels/icons.js",
      "src/maps/sceneApply.js",
      "src/layers/localAdsb/qaDrawn.js",
-      "src/ui/imageryBoxNavara.js",
      "src/geo/",
      "src/time/clock.js",
      "src/globe/navara/overlay.js",
@@ -6,9 +6,10 @@ import { FEATURE_SOURCE_METHODS } from '../sources/featureSource.js';
 import { createAnnotationResolver } from './resolver.js';
 import { createAnnotationEngine } from './annotationEngine.js';
 import { _resetRenderGovernorForTest } from '../renderGovernor.js';
+import { cameraOnlyEngine } from '../testSupport/viewerEngine.mjs';

 function viewerAt(lat, lon, height = 20_000) {
-  return {
+  return cameraOnlyEngine({
    camera: {
      positionCartographic: {
        latitude: (lat * Math.PI) / 180,
@@ -16,7 +17,7 @@ function viewerAt(lat, lon, height = 20_000) {
        height,
      },
    },
-  };
+  });
 }

 /** A resolver whose boundary lookups and geocoder record every call. */
@@ -45,7 +46,7 @@ function harness(place = null) {
  const resolve = (target, viewer, extra = {}) =>
    resolveAnnotationTarget({
      placeSearch,
-      viewer,
+      engine: viewer,
      target,
      footprint: true,
      deferFootprint: true,
@@ -287,7 +288,7 @@ test('the engine keeps every part on the mark, drawn at once or upgraded', async
    destroy() {},
  };
  const engine = createAnnotationEngine({
-    viewer: {},
+    globe: {},
    renderer,
    resolveTarget: async ({ target }) =>
      target === 'now'
@@ -1,8 +1,6 @@
 import { isUnavailableCapability } from '../sources/capability.js';
 import { defaultGeospatial } from '../search/defaults.js';
-import * as Cesium from 'cesium';
 import * as geo from '../geo/index.js';
-import { isGlobeEngine } from '../globe/contract.js';
 import { greatCircleMeters } from '../geoDistance.js';
 import {
  holdContinuousRender,
@@ -22,16 +20,6 @@ import {
 } from '../sources/phaseTiming.js';
 import { formatDistanceText } from '../data/distanceFormat.js';

-// Dev convenience: expose the app's Cesium instance for console/preview probing
-// (single shared module instance — avoids dual-Cesium state bugs when testing).
-// A getter, because the production build's Cesium global loads only with the
-// first Cesium globe.
-if (typeof window !== 'undefined' && !('__CESIUM__' in window))
-  Object.defineProperty(window, '__CESIUM__', {
-    configurable: true,
-    get: () => Cesium,
-  });
-
 /**
 * Annotation engine — the voice agent's "whiteboard" over the 3D world.
 *
@@ -148,7 +136,7 @@ const DETACHED_RENDERER = Object.freeze({

 export function createAnnotationEngine({
  placeSearch = defaultGeospatial,
-  viewer = null,
+  globe = null,
  renderer = DETACHED_RENDERER,
  outlineRetryDelaysMs = OUTLINE_RETRY_DELAYS_MS,
  resolveTarget = resolveAnnotationTarget,
@@ -428,7 +416,7 @@ export function createAnnotationEngine({
   * @returns {Promise<{ok, drawn, failed, ids, results}>}
   */
  async function annotate(requests, opts = {}) {
-    if (destroyed || !viewer)
+    if (destroyed || !globe)
      return {
        ok: false,
        drawn: 0,
@@ -437,7 +425,7 @@ export function createAnnotationEngine({
        results: [],
        error: destroyed
          ? 'destroyed'
-          : 'Annotations are drawn on the Cesium globe only.',
+          : 'Annotations are drawn on a globe only.',
      };
    const list = (Array.isArray(requests) ? requests : [requests]).map(
      promoteStreetHighlight,
@@ -914,7 +902,7 @@ export function createAnnotationEngine({
    const type = normalizeType(spec?.type);
    // MANUAL geometry (drawTool.js): the person clicked the vertices, so there is
    // nothing to resolve. Same record shapes as a resolved spec, source 'manual'.
-    if (isManualSpec(spec, type)) return resolveManualSpec(spec, type, viewer);
+    if (isManualSpec(spec, type)) return resolveManualSpec(spec, type, globe);
    if (type === 'route') {
      const points = Array.isArray(spec.points) ? spec.points : [];
      if (points.length < 2)
@@ -925,7 +913,7 @@ export function createAnnotationEngine({
        const name = pt.target ?? pt.name ?? null;
        const r = await resolveTarget({
          placeSearch,
-          viewer,
+          engine: globe,
          target: name,
          latitude: pt.latitude,
          longitude: pt.longitude,
@@ -983,7 +971,7 @@ export function createAnnotationEngine({
    if (type === 'arrow') {
      const from = await resolveTarget({
        placeSearch,
-        viewer,
+        engine: globe,
        target: spec.target,
        latitude: spec.latitude,
        longitude: spec.longitude,
@@ -995,7 +983,7 @@ export function createAnnotationEngine({
      });
      const to = await resolveTarget({
        placeSearch,
-        viewer,
+        engine: globe,
        target: spec.toTarget,
        latitude: spec.toLatitude,
        longitude: spec.toLongitude,
@@ -1028,7 +1016,7 @@ export function createAnnotationEngine({
      type === 'area' ? spec.footprint !== false : Boolean(spec.footprint);
    return resolveTarget({
      placeSearch,
-      viewer,
+      engine: globe,
      target: spec.target,
      latitude: spec.latitude,
      longitude: spec.longitude,
@@ -1669,7 +1657,7 @@ export function createAnnotationEngine({
  /** Fly the camera to one mark; a line is framed whole, not by its start. */
  function frame(id) {
    const anno = annotations.get(id);
-    if (!anno || !viewer) return false;
+    if (!anno || !globe) return false;
    if (anno.type === 'route' && anno.path?.length) {
      const ring = anno.path.map((p) => [p.lon, p.lat]);
      // Unwrap around the first vertex, as ringRange does, so a line across
@@ -1739,7 +1727,7 @@ export function createAnnotationEngine({
      const cart = points.map((p) =>
        geo.cartesian3.fromDegrees(p.lon, p.lat, p.height || 0),
      );
-      const sphere = Cesium.BoundingSphere.fromPoints(cart);
+      const sphere = geo.boundingSphere.fromPoints(cart);
      flyToSphere(sphere.center, sphere.radius, {
        pitch: geo.math.toRadians(-35),
        range: Math.max(900, sphere.radius * 2.6),
@@ -1755,23 +1743,7 @@ export function createAnnotationEngine({
  function isPointOnScreen(p) {
    try {
      const pos = geo.cartesian3.fromDegrees(p.lon, p.lat, p.height || 0);
-      if (isGlobeEngine(viewer)) return engineSeesPoint(viewer, pos);
-      const camera = viewer.camera;
-      const cv = camera.frustum.computeCullingVolume(
-        camera.position,
-        camera.direction,
-        camera.up,
-      );
-      if (
-        cv.computeVisibility(new Cesium.BoundingSphere(pos, 1)) ===
-        Cesium.Intersect.OUTSIDE
-      )
-        return false;
-      const occluder = new Cesium.EllipsoidalOccluder(
-        Cesium.Ellipsoid.WGS84,
-        camera.position,
-      );
-      return occluder.isPointVisible(pos);
+      return engineSeesPoint(globe, pos);
    } catch {
      return true;
    }
@@ -1810,28 +1782,13 @@ export function createAnnotationEngine({
  }

  /**
-   * Fly to a sphere keeping the camera's heading: Cesium's
-   * flyToBoundingSphere on a viewer, the contract's flyToSphere on a globe
-   * engine (the same offset semantics).
+   * Fly to a sphere keeping the camera's heading (the contract's
+   * flyToSphere: Cesium's flyToBoundingSphere offset).
   */
  function flyToSphere(center, radius, { pitch, range, duration }) {
-    if (isGlobeEngine(viewer)) {
-      viewer.camera.flyToSphere(
-        { center, radius },
-        { heading: viewer.camera.pose().heading, pitch, range, duration },
-      );
-      return;
-    }
-    viewer.camera.flyToBoundingSphere(
-      new Cesium.BoundingSphere(center, radius),
-      {
-        offset: new Cesium.HeadingPitchRange(
-          viewer.camera.heading,
-          pitch,
-          range,
-        ),
-        duration,
-      },
+    globe.camera.flyToSphere(
+      { center, radius },
+      { heading: globe.camera.pose().heading, pitch, range, duration },
    );
  }

@@ -1861,7 +1818,7 @@ export function createAnnotationEngine({
      generation++;
      const previous = renderer;
      renderer = DETACHED_RENDERER;
-      viewer = null;
+      globe = null;
      for (const anno of annotations.values()) {
        anno.pendingOutline = false;
        try {
@@ -1877,13 +1834,13 @@ export function createAnnotationEngine({
      }
    },
    /**
-     * Draw the board on a globe: `viewer` and the `renderer` built for it.
-     * Marks kept while no globe drew them appear again as they were.
+     * Draw the board on a globe: its `engine` and the `renderer` built for
+     * it. Marks kept while no globe drew them appear again as they were.
     */
-    attachRenderer({ viewer: nextViewer, renderer: nextRenderer }) {
+    attachRenderer({ engine: nextGlobe = null, renderer: nextRenderer }) {
      if (destroyed) return;
      engine.detachRenderer();
-      viewer = nextViewer;
+      globe = nextGlobe;
      renderer = nextRenderer ?? DETACHED_RENDERER;
      for (const anno of annotations.values()) {
        try {
@@ -2093,7 +2050,7 @@ export function createAnnotationEngine({
  }) {
    if (destroyed) return;
    try {
-      viewer?.camera.flyTo({
+      globe?.camera.flyTo({
        destination: geo.cartesian3.fromDegrees(lon, lat, height),
        orientation: {
          heading: geo.math.toRadians(heading),
@@ -2371,7 +2328,7 @@ function manualPairs(list) {
 * (not synthesized) outline so it drapes solid; a line is a `route` with mode
 * 'manual', its length as distance and no travel time; a pin is a point.
 */
-function resolveManualSpec(spec, type, viewer) {
+function resolveManualSpec(spec, type, globe) {
  if (type === 'route') {
    // height 0 is a placeholder, not a placement: the world renderer draws a
    // route with clampToGround + CESIUM_3D_TILE classification, so the line is
@@ -2412,7 +2369,7 @@ function resolveManualSpec(spec, type, viewer) {
    return {
      lon,
      lat,
-      height: sampleGroundHeight(viewer, lon, lat),
+      height: sampleGroundHeight(globe, lon, lat),
      ring,
      ...(polygons ? { polygons } : {}),
      footprintKind: 'area',
@@ -2427,7 +2384,7 @@ function resolveManualSpec(spec, type, viewer) {
  return {
    lon,
    lat,
-    height: sampleGroundHeight(viewer, lon, lat),
+    height: sampleGroundHeight(globe, lon, lat),
    ring: null,
    source: 'manual',
  };
@@ -2490,8 +2447,8 @@ function appendDistance(baseLabel, distM) {

 /**
 * Whether a globe engine shows a world point: in front of the camera, inside
- * the canvas and on the near side of the globe (what the Cesium path's
- * culling volume and ellipsoid occluder answer).
+ * the canvas and on the near side of the globe (what Cesium's culling
+ * volume and ellipsoid occluder answer).
 */
 function engineSeesPoint(engine, position) {
  if (!engine.projector.horizonVisible(position)) return false;
@@ -241,7 +241,7 @@ test('outline queue: an 8-spec batch keeps at most two FIFO upgrades in flight',
    };
  };
  const engine = createAnnotationEngine({
-    viewer: {},
+    globe: {},
    renderer,
    resolveTarget,
  });
@@ -313,7 +313,7 @@ test('outline queue: clear drops queued-but-unstarted upgrades without a later f
      }),
  });
  engine = createAnnotationEngine({
-    viewer: {},
+    globe: {},
    renderer,
    resolveTarget,
  });
@@ -379,7 +379,7 @@ test('retry: HTTP 429 Retry-After 5s gets one ladder-spaced retry; a second 429
  });

  const resolved = await resolveAnnotationTarget({
-    viewer: {},
+    globe: {},
    target: 'PT2 rate-limit fixture',
    latitude: 12.345,
    longitude: 67.89,
@@ -453,7 +453,7 @@ test('retry: a plain HTTP 500 still exhausts the existing 8s/25s transient ladde
  });

  const resolved = await resolveAnnotationTarget({
-    viewer: {},
+    globe: {},
    target: 'PT2 transient fixture',
    latitude: -12.345,
    longitude: -67.89,
@@ -603,8 +603,8 @@ test('outline upgrade updates the rendered element in place without remove/add',
    remove() { calls.remove += 1; },
    sync() {},
  };
-  const viewer = {};
-  const engine = createAnnotationEngine({ viewer, renderer, placeSearch: createStandalonePlaceSearch({ resolveApiKey: () => 'unit-test-key' }) });
+  const globe = {};
+  const engine = createAnnotationEngine({ globe, renderer, placeSearch: createStandalonePlaceSearch({ resolveApiKey: () => 'unit-test-key' }) });
  const upgraded = new Promise((resolve) => engine.onOutlineEvent(resolve));

  const result = await engine.annotate([{
@@ -715,7 +715,7 @@ test('fresh async building batch reserves slots together and releases failed/cle
  t.after(() => _resetRenderGovernorForTest());
  const h = controlledBuildingRenderer();
  const engine = createAnnotationEngine({
-    viewer: {},
+    globe: {},
    renderer: h.renderer,
    resolveTarget: async ({ target }) => ({
      ...BUILDING_FP,
@@ -762,7 +762,7 @@ test('outline workers retain completion ownership and clear cancels resolved-but
  const h = controlledBuildingRenderer();
  const started = [];
  const engine = createAnnotationEngine({
-    viewer: {},
+    globe: {},
    renderer: h.renderer,
    resolveTarget: async ({ target }) => ({
      ...FIXED_POINT,
@@ -805,7 +805,7 @@ test('building recaption timeout retains old route and a newer replacement owns
  installAnimationFrameStubs(t);
  const h = controlledBuildingRenderer();
  const engine = createAnnotationEngine({
-    viewer: {},
+    globe: {},
    renderer: h.renderer,
    resolveTarget: async () => ({ ...BUILDING_FP }),
  });
@@ -860,7 +860,7 @@ test('replacement cleanup failure still removes the old route and retains failed
  installAnimationFrameStubs(t);
  const h = controlledBuildingRenderer();
  const engine = createAnnotationEngine({
-    viewer: {}, renderer: h.renderer, resolveTarget: async () => ({ ...BUILDING_FP }),
+    globe: {}, renderer: h.renderer, resolveTarget: async () => ({ ...BUILDING_FP }),
  });
  const initial = engine.annotate([{ type: 'area', target: 'Capitol', label: 'Old' }]);
  await flushMicrotasks();
@@ -905,7 +905,7 @@ test('identical refresh revokes an older building replacement even if cancellati
  installAnimationFrameStubs(t);
  const h = controlledBuildingRenderer();
  const engine = createAnnotationEngine({
-    viewer: {}, renderer: h.renderer, resolveTarget: async () => ({ ...BUILDING_FP }),
+    globe: {}, renderer: h.renderer, resolveTarget: async () => ({ ...BUILDING_FP }),
  });
  const initial = engine.annotate([{ type: 'area', target: 'Capitol', label: 'Old' }]);
  await flushMicrotasks(); h.pending[0].finish(); await initial;
@@ -936,7 +936,7 @@ test('successful replacement survives failed old-route retirement and keeps clea
  installAnimationFrameStubs(t);
  const h = controlledBuildingRenderer();
  const engine = createAnnotationEngine({
-    viewer: {}, renderer: h.renderer, resolveTarget: async () => ({ ...BUILDING_FP }),
+    globe: {}, renderer: h.renderer, resolveTarget: async () => ({ ...BUILDING_FP }),
  });
  const initial = engine.annotate([{ type: 'area', target: 'Capitol', label: 'Old' }]);
  await flushMicrotasks(); h.pending[0].finish(); await initial;
@@ -975,7 +975,7 @@ test('pending fresh predecessor failure cannot erase a newer building intent', a
  globalThis.requestAnimationFrame = (callback) => { frames.push(callback); return frames.length; };
  const h = controlledBuildingRenderer();
  const engine = createAnnotationEngine({
-    viewer: {}, renderer: h.renderer, resolveTarget: async () => ({ ...BUILDING_FP }),
+    globe: {}, renderer: h.renderer, resolveTarget: async () => ({ ...BUILDING_FP }),
  });
  const first = engine.annotate([{ type: 'area', target: 'Capitol', label: 'First' }]);
  await flushMicrotasks();
@@ -1004,7 +1004,7 @@ test('duplicate pending building results reflect final failure rather than a dea
  installAnimationFrameStubs(t);
  const h = controlledBuildingRenderer();
  const engine = createAnnotationEngine({
-    viewer: {}, renderer: h.renderer, resolveTarget: async () => ({ ...BUILDING_FP }),
+    globe: {}, renderer: h.renderer, resolveTarget: async () => ({ ...BUILDING_FP }),
  });
  const spec = { type: 'area', target: 'Capitol', label: 'Same' };
  const batch = engine.annotate([spec, spec]);
@@ -1023,7 +1023,7 @@ test('separate duplicate callers observe the original building install outcome',
  for (const outcome of ['installed', 'failed', 'timeout', 'clear']) {
    const h = controlledBuildingRenderer();
    const engine = createAnnotationEngine({
-      viewer: {},
+      globe: {},
      renderer: h.renderer,
      resolveTarget: async () => ({ ...BUILDING_FP }),
    });
@@ -1077,7 +1077,7 @@ test('a duplicate joins the physical deferred install but not another outline lo
  const h = controlledBuildingRenderer();
  let lookups = 0;
  const engine = createAnnotationEngine({
-    viewer: {},
+    globe: {},
    renderer: h.renderer,
    resolveTarget: async () => ({
      ...FIXED_POINT,
@@ -1119,7 +1119,7 @@ test('duplicate-replacement: a renderer throw leaves no phantom mark and no leak

  const { renderer, failAddOnce } = throwingRendererHarness();
  const engine = createAnnotationEngine({
-    viewer: {},
+    globe: {},
    renderer,
    resolveTarget: async () => ({ ...FIXED_POINT }),
  });
@@ -1173,7 +1173,7 @@ test('fresh path: a renderer throw is rolled back the same way', async (t) => {

  const { renderer, failAddOnce } = throwingRendererHarness();
  const engine = createAnnotationEngine({
-    viewer: {},
+    globe: {},
    renderer,
    resolveTarget: async () => ({ ...FIXED_POINT }),
  });
@@ -1237,7 +1237,7 @@ test('fresh path: a throw AFTER partial renderer state leaves nothing on the boa

  const { renderer, failAddOnce, live } = partialStateRendererHarness();
  const engine = createAnnotationEngine({
-    viewer: {},
+    globe: {},
    renderer,
    resolveTarget: async () => ({ ...FIXED_POINT }),
  });
@@ -1278,7 +1278,7 @@ test('duplicate-replacement: a throw AFTER partial renderer state leaves nothing

  const { renderer, failAddOnce, live } = partialStateRendererHarness();
  const engine = createAnnotationEngine({
-    viewer: {},
+    globe: {},
    renderer,
    resolveTarget: async () => ({ ...FIXED_POINT }),
  });
@@ -1335,7 +1335,7 @@ test('destroy releases the renderer and prevents subsequent annotation work', as
  renderer.destroy = () => {
    destroyed++;
  };
-  const engine = createAnnotationEngine({ viewer: {}, renderer });
+  const engine = createAnnotationEngine({ globe: {}, renderer });
  const drawn = await engine.annotate([
    { type: 'pin', longitude: -97.74, latitude: 30.27 },
  ]);
@@ -1360,7 +1360,7 @@ test('a late annotation resolver cannot redraw after destruction', async (t) =>
  let release;
  let signal;
  const engine = createAnnotationEngine({
-    viewer: {},
+    globe: {},
    renderer,
    resolveTarget: (options) => {
      signal = options.signal;
@@ -1385,9 +1385,10 @@ test('caller cancellation prevents a late annotation and camera mutation', async
  let resolverSignal;
  let flights = 0;
  const engine = createAnnotationEngine({
-    viewer: {
+    globe: {
      camera: {
-        flyToBoundingSphere() {
+        pose: () => ({ heading: 0 }),
+        flyToSphere() {
          flights += 1;
        },
      },
@@ -1424,7 +1425,7 @@ test('only an explicit navigation request permits resolving distant annotation t
  renderer.destroy = () => {};
  const received = [];
  const engine = createAnnotationEngine({
-    viewer: {},
+    globe: {},
    renderer,
    resolveTarget: async (options) => {
      received.push(options);
@@ -1448,7 +1449,7 @@ test('recaption inherits outline credit from borrowed geometry rather than its n
  const { renderer } = fakeRenderer();
  let first = true;
  const ring = [[-99,31],[-98.99,31],[-98.99,31.01],[-99,31]];
-  const engine = createAnnotationEngine({ viewer: {}, renderer,
+  const engine = createAnnotationEngine({ globe: {}, renderer,
    resolveTarget: async () => {
      if (first) { first = false; return { ...FIXED_POINT, ring, footprintKind: 'area', outlineCredit: 'tiles' }; }
      return { ...FIXED_POINT, source: 'osm-local', resolveOutline: async () => null };
@@ -1471,7 +1472,7 @@ test('hand-drawn marks: one mark can be hidden, renamed, recoloured, framed and
  const { renderer, calls } = fakeRenderer();
  const flights = [];
  const engine = createAnnotationEngine({
-    viewer: { camera: { heading: 0, flyToBoundingSphere: (sphere) => flights.push(sphere) } },
+    globe: { camera: { pose: () => ({ heading: 0 }), flyToSphere: (sphere) => flights.push(sphere) } },
    renderer,
  });
  let changes = 0;
@@ -1540,10 +1541,10 @@ test('hand-drawn marks: remove, hide, clear, expiry and framing have their effec
  const { renderer, calls } = fakeRenderer();
  const flights = [];
  const engine = createAnnotationEngine({
-    viewer: {
+    globe: {
      camera: {
-        heading: 0,
-        flyToBoundingSphere: (sphere) => flights.push(sphere),
+        pose: () => ({ heading: 0 }),
+        flyToSphere: (sphere) => flights.push(sphere),
      },
    },
    renderer,
@@ -1638,7 +1639,7 @@ test('hand-drawn marks: a voice mark or a hidden mark is not taken as their dupl
  _resetRenderGovernorForTest();
  t.after(() => _resetRenderGovernorForTest());
  const { renderer } = fakeRenderer();
-  const engine = createAnnotationEngine({ viewer: {}, renderer });
+  const engine = createAnnotationEngine({ globe: {}, renderer });
  await engine.annotate(
    [
      {
@@ -1691,7 +1692,7 @@ test('hand-drawn marks: only a manual mark can be restyled', async (t) => {
  t.after(() => _resetRenderGovernorForTest());
  const { renderer } = fakeRenderer();
  const engine = createAnnotationEngine({
-    viewer: {},
+    globe: {},
    renderer,
    resolveTarget: async () => ({ ...FIXED_POINT }),
  });
@@ -1706,7 +1707,7 @@ test('a drawn line that rounds up to the next unit is labelled in it, not as 100
  installAnimationFrameStubs(t);
  const labels = [];
  const renderer = { add(anno) { labels.push(anno.label); }, update() {}, remove() {}, sync() {}, destroy() {} };
-  const engine = createAnnotationEngine({ viewer: {}, renderer });
+  const engine = createAnnotationEngine({ globe: {}, renderer });
  const metresPerDegree = (6371.0088 * 1000 * Math.PI) / 180;
  for (const metres of [994, 996, 9940, 9960]) {
    await engine.annotate([
@@ -1722,7 +1723,7 @@ test('hand-drawn marks: two unnamed pins close together are two pins, whatever t
  _resetRenderGovernorForTest();
  t.after(() => _resetRenderGovernorForTest());
  const { renderer } = fakeRenderer();
-  const engine = createAnnotationEngine({ viewer: {}, renderer });
+  const engine = createAnnotationEngine({ globe: {}, renderer });
  const pin = (lon, color) => ({ type: 'pin', manual: true, latitude: 30.27, longitude: lon, label: '', color });
  await engine.annotate([pin(-97.74, 'primary')], { persist: true });
  await engine.annotate([pin(-97.7402, 'primary')], { persist: true });
@@ -1740,7 +1741,7 @@ test('hand-drawn marks: hiding a mark before its first frame takes it off at onc
  t.after(() => _resetRenderGovernorForTest());
  let syncs = 0;
  const renderer = { add() {}, update() {}, remove() {}, sync() { syncs += 1; }, destroy() {} };
-  const engine = createAnnotationEngine({ viewer: {}, renderer });
+  const engine = createAnnotationEngine({ globe: {}, renderer });
  await engine.annotate([{ type: 'pin', manual: true, latitude: 1, longitude: 1 }], { persist: true });
  const [mark] = engine.list();
  const before = syncs;
@@ -1759,7 +1760,7 @@ test('hand-drawn marks: with every mark hidden the scene idles, and showing one
  let renders = 0;
  installRenderGovernor({ scene: { requestRenderMode: true, requestRender: () => (renders += 1) } });
  const { renderer } = fakeRenderer();
-  const engine = createAnnotationEngine({ viewer: {}, renderer });
+  const engine = createAnnotationEngine({ globe: {}, renderer });
  await engine.annotate([
    { type: 'pin', manual: true, latitude: 1, longitude: 1 },
    { type: 'pin', manual: true, latitude: 2, longitude: 2 },
@@ -1784,7 +1785,7 @@ test('hand-drawn marks: a restyle the renderer cannot draw takes the mark off an
  const { renderer, failAddOnce } = throwingRendererHarness();
  let syncs = 0;
  renderer.sync = () => (syncs += 1);
-  const engine = createAnnotationEngine({ viewer: {}, renderer });
+  const engine = createAnnotationEngine({ globe: {}, renderer });
  await engine.annotate([{ type: 'pin', manual: true, latitude: 1, longitude: 1 }], { persist: true });
  const [mark] = engine.list();
  let changes = 0;
@@ -1811,7 +1812,7 @@ test('hand-drawn marks: a mark shown again right after it was drawn appears at o
  });
  const tick = () => queued.splice(0).forEach((callback) => callback());
  const { renderer } = fakeRenderer();
-  const engine = createAnnotationEngine({ viewer: {}, renderer });
+  const engine = createAnnotationEngine({ globe: {}, renderer });
  await engine.annotate([{ type: 'pin', manual: true, latitude: 1, longitude: 1 }], { persist: true });
  const [mark] = engine.list();
  engine.setHidden(mark.id, true);
@@ -1832,7 +1833,7 @@ test('removing one mark whose cleanup fails keeps it addressable for a retry', a
    calls.remove += 1;
    if (failRemove) throw new Error('renderer remove failed');
  };
-  const engine = createAnnotationEngine({ viewer: { camera: { heading: 0 } }, renderer });
+  const engine = createAnnotationEngine({ globe: { camera: { pose: () => ({ heading: 0 }) } }, renderer });
  await engine.annotate([
    { type: 'pin', manual: true, latitude: 30.27, longitude: -97.74, label: 'Camp' },
  ], { persist: true });
@@ -1850,7 +1851,7 @@ test('a building install in the batch does not re-judge marks that never install
  installAnimationFrameStubs(t);
  const h = controlledBuildingRenderer();
  const engine = createAnnotationEngine({
-    viewer: {},
+    globe: {},
    renderer: h.renderer,
    resolveTarget: async ({ target }) =>
      target === 'Tower' ? { ...BUILDING_FP, lon: -97.7 } : { ...FIXED_POINT },
@@ -1873,7 +1874,7 @@ test('plain recaption keeps the old mark addressable when its removal throws', a
  installAnimationFrameStubs(t);
  const { renderer } = fakeRenderer();
  const engine = createAnnotationEngine({
-    viewer: {}, renderer, resolveTarget: async () => ({ ...FIXED_POINT }),
+    globe: {}, renderer, resolveTarget: async () => ({ ...FIXED_POINT }),
  });
  await engine.annotate([{ type: 'point', target: 'Capitol', label: 'Capitol' }]);
  const old = engine.list()[0];
@@ -19,6 +19,7 @@ import {
  refineScope,
  isGroundsLikeAsk,
 } from './annotationResolver.js';
+import { cameraOnlyEngine } from '../testSupport/viewerEngine.mjs';

 // Build a square way of ~`areaM2` centred `dLatM`/`dLonM` metres from an anchor,
 // in Overpass `out geom` element shape ({ tags, geometry: [{lat,lon}...] }).
@@ -157,7 +158,7 @@ test('refineScope: entityKind refines only an unresolved (auto) scope', () => {
 });

 function closeViewportViewer() {
-  return {
+  return cameraOnlyEngine({
    camera: {
      positionCartographic: {
        latitude: 30.2672 * Math.PI / 180,
@@ -165,7 +166,7 @@ function closeViewportViewer() {
        height: 1000,
      },
    },
-  };
+  });
 }

 function geocodePayload({ lat, lon, types, label }) {
@@ -221,7 +222,7 @@ test('ask-side admin bypass: "the Texas Capitol" recovers near-view despite a fa
  });

  const resolved = await resolveAnnotationTarget({
-    viewer: closeViewportViewer(),
+    engine: closeViewportViewer(),
    target: 'the Texas Capitol',
  });

@@ -245,7 +246,7 @@ test('ask-side admin bypass: explicit "state of Texas" skips recovery and proxim
  });

  const resolved = await resolveAnnotationTarget({
-    viewer: closeViewportViewer(),
+    engine: closeViewportViewer(),
    target: 'state of Texas',
  });

@@ -286,7 +287,7 @@ for (const fixture of [
    });

    const resolved = await resolveAnnotationTarget({
-      viewer: closeViewportViewer(),
+      engine: closeViewportViewer(),
      target: fixture.target,
    });

@@ -312,7 +313,7 @@ test('ask-side admin bypass: bare "Texas" remains on the guarded recovery path',
  });

  const resolved = await resolveAnnotationTarget({
-    viewer: closeViewportViewer(),
+    engine: closeViewportViewer(),
    target: 'Texas',
  });

@@ -351,7 +352,7 @@ test('ask-side admin bypass: admin level 2/3 result types never grant a township

  for (const target of fixtures.keys()) {
    const resolved = await resolveAnnotationTarget({
-      viewer: closeViewportViewer(),
+      engine: closeViewportViewer(),
      target,
    });
    assert.ok(resolved);
@@ -369,11 +370,11 @@ test('ask-side admin bypass: admin level 2/3 result types never grant a township
 // Synthetic footprints reproduce the real Capitol/YOTEL selection without live APIs.
 const CAPITOL_ANCHOR = { lat: 38.8899389, lon: -77.0090505 };
 function capitolViewer() {
-  return { camera: { positionCartographic: {
+  return cameraOnlyEngine({ camera: { positionCartographic: {
    latitude: CAPITOL_ANCHOR.lat * Math.PI / 180,
    longitude: CAPITOL_ANCHOR.lon * Math.PI / 180,
    height: 1000,
-  } } };
+  } } });
 }
 function installCapitolMocks(t, elements, components = [
  { long_name: 'Washington', types: ['locality', 'political'] },
@@ -401,7 +402,7 @@ for (const [target, deferFootprint] of [
    const capitol = squareWay(CAPITOL_ANCHOR, 0, 0, 20000, { building: 'yes', name: 'United States Capitol' });
    const hotel = squareWay(CAPITOL_ANCHOR, 620, -140, 3000, { building: 'yes', tourism: 'hotel', name: 'YOTEL Washington DC' });
    installCapitolMocks(t, [hotel, capitol]);
-    const result = await resolveAnnotationTarget({ viewer: capitolViewer(), target, entityKind: 'building', footprint: true, deferFootprint });
+    const result = await resolveAnnotationTarget({ engine: capitolViewer(), target, entityKind: 'building', footprint: true, deferFootprint });
    assert.ok(result);
    const outline = deferFootprint ? await result.resolveOutline() : result;
    assert.deepEqual(outline.ring, capitol.geometry.map(p => [p.lon, p.lat]));
@@ -412,7 +413,7 @@ for (const [target, deferFootprint] of [
 test('address-only landmark without a matching outline keeps its geocoded point', async t => {
  const hotel = squareWay(CAPITOL_ANCHOR, 620, -140, 3000, { building: 'yes', tourism: 'hotel', name: 'YOTEL Washington DC' });
  installCapitolMocks(t, [hotel]);
-  const result = await resolveAnnotationTarget({ viewer: capitolViewer(), target: 'US Capitol building, Washington', entityKind: 'building', footprint: true, deferFootprint: true });
+  const result = await resolveAnnotationTarget({ engine: capitolViewer(), target: 'US Capitol building, Washington', entityKind: 'building', footprint: true, deferFootprint: true });
  assert.ok(result);
  assert.deepEqual([result.lat, result.lon], [CAPITOL_ANCHOR.lat, CAPITOL_ANCHOR.lon]);
  assert.equal(await result.resolveOutline(), null);
@@ -422,7 +423,7 @@ test('missing address components do not turn a formatted city address into the l
  const capitol = squareWay(CAPITOL_ANCHOR, 0, 0, 20000, { building: 'yes', name: 'United States Capitol' });
  const hotel = squareWay(CAPITOL_ANCHOR, 620, -140, 3000, { building: 'yes', name: 'YOTEL Washington DC' });
  installCapitolMocks(t, [hotel, capitol], []);
-  const result = await resolveAnnotationTarget({ viewer: capitolViewer(), target: 'United States Capitol building', footprint: true });
+  const result = await resolveAnnotationTarget({ engine: capitolViewer(), target: 'United States Capitol building', footprint: true });
  assert.deepEqual(result.ring, capitol.geometry.map(p => [p.lon, p.lat]));
 });

@@ -430,7 +431,7 @@ test('a genuine geocoded feature name still canonicalizes an alternate user name
  const capitol = squareWay(CAPITOL_ANCHOR, 0, 0, 20000, { building: 'yes', name: 'United States Capitol' });
  const decoy = squareWay(CAPITOL_ANCHOR, 620, -140, 3000, { building: 'yes', name: 'Congress meeting building' });
  installCapitolMocks(t, [decoy, capitol], [{ long_name: 'United States Capitol', types: ['landmark'] }]);
-  const result = await resolveAnnotationTarget({ viewer: capitolViewer(), target: 'Congress meeting building', footprint: true });
+  const result = await resolveAnnotationTarget({ engine: capitolViewer(), target: 'Congress meeting building', footprint: true });
  assert.deepEqual(result.ring, capitol.geometry.map(p => [p.lon, p.lat]));
 });

@@ -479,7 +480,7 @@ test('keyless: a key that geocodes to nothing still anchors the annotation', asy
  });

  const resolved = await resolveAnnotationTarget({
-    viewer: closeViewportViewer(),
+    engine: closeViewportViewer(),
    target: 'Lady Bird Lake',
  });

@@ -534,7 +535,7 @@ test('keyless: OSM matching uses the feature\'s canonical name, not the user\'s
  });

  const resolved = await resolveAnnotationTarget({
-    viewer: closeViewportViewer(),
+    engine: closeViewportViewer(),
    target: 'the monument near the Texas Capitol, Austin',
    footprint: true,
  });
@@ -581,11 +582,11 @@ test('keyless: a Photon outage is not remembered as "no such place"', async (t)
  });

  const target = 'Waller Creek';
-  assert.equal(await resolveAnnotationTarget({ viewer: closeViewportViewer(), target }), null);
+  assert.equal(await resolveAnnotationTarget({ engine: closeViewportViewer(), target }), null);
  const duringOutage = requests.length;

  photonReachable = true;
-  const retried = await resolveAnnotationTarget({ viewer: closeViewportViewer(), target });
+  const retried = await resolveAnnotationTarget({ engine: closeViewportViewer(), target });

  assert.ok(retried, 'the same target must resolve once the network is back');
  assert.deepEqual([retried.lat, retried.lon], [30.2665, -97.7385]);
@@ -47,7 +47,7 @@ test('the marks survive a globe leaving and are drawn again on the next one', as
  withAnimationFrames(t);
  const log = [];
  const engine = createAnnotationEngine({
-    viewer: {},
+    globe: {},
    renderer: recordingRenderer(log, 'cesium'),
    resolveTarget: async () => ({ ...BUILDING }),
  });
@@ -69,7 +69,7 @@ test('the marks survive a globe leaving and are drawn again on the next one', as

  log.length = 0;
  engine.attachRenderer({
-    viewer: {},
+    engine: {},
    renderer: recordingRenderer(log, 'next'),
  });
  assert.deepEqual(log, ['next add Capitol']);
@@ -83,13 +83,13 @@ test('detaching twice and attaching over an attached globe release each drawing
  withAnimationFrames(t);
  const log = [];
  const engine = createAnnotationEngine({
-    viewer: {},
+    globe: {},
    renderer: recordingRenderer(log, 'a'),
  });
  engine.detachRenderer();
  engine.detachRenderer();
-  engine.attachRenderer({ viewer: {}, renderer: recordingRenderer(log, 'b') });
-  engine.attachRenderer({ viewer: {}, renderer: recordingRenderer(log, 'c') });
+  engine.attachRenderer({ engine: {}, renderer: recordingRenderer(log, 'b') });
+  engine.attachRenderer({ engine: {}, renderer: recordingRenderer(log, 'c') });
  assert.deepEqual(log, ['a destroy', 'b destroy']);
  engine.destroy();
 });
@@ -67,15 +67,17 @@ const PREVIEW = DRAW_COLOR_CSS;
 * through the actions it gives `connect`, which returns their disconnect.
 * A row's fly-to is an immediate navigation through `navigation`, like
 * Import's, so Cockpit can refuse it and a running orbit or follow lets go.
- * The globe it draws on is a Cesium `viewer` or a draw `surface` factory
- * (`surface({ session, cursor })`: the input and preview of a globe without
- * a viewer, src/annotations/drawInputNavara.js), which gets the open shape
- * and the rubber band's end as live getters.
- * @param {{viewer?: Cesium.Viewer, surface?: Function, annotations: {annotate: Function, clear: Function}, navigation?: object, publish?: Function, connect?: Function}} deps
+ * The globe it draws on is a Cesium `viewer` (with its `engine`, which
+ * answers the picks) or a draw `surface` factory (`surface({ session,
+ * cursor })`: the input and preview of a globe without a viewer,
+ * src/annotations/drawInputNavara.js), which gets the open shape and the
+ * rubber band's end as live getters.
+ * @param {{viewer?: Cesium.Viewer, engine?: object, surface?: Function, annotations: {annotate: Function, clear: Function}, navigation?: object, publish?: Function, connect?: Function}} deps
 * @returns {{destroy: Function}|null}
 */
 export function initDrawTool({
  viewer = null,
+  engine = null,
  surface: makeSurface = null,
  annotations,
  navigation = null,
@@ -119,7 +121,7 @@ export function initDrawTool({
  const live = { session: () => session, cursor: () => cursor };
  const surface = makeSurface
    ? makeSurface(live)
-    : cesiumDrawSurface(viewer, live);
+    : cesiumDrawSurface(viewer, engine, live);

  const present = () =>
    publish({
@@ -485,7 +487,7 @@ export function initDrawTool({
 * click actions on its own handler (select, track); they are borrowed while a
 * sketch is open and given back on the way out.
 */
-function cesiumDrawSurface(viewer, live) {
+function cesiumDrawSurface(viewer, engine, live) {
  const previewEntities = [];
  const dataSource = new Cesium.CustomDataSource(PREVIEW_DATA_SOURCE_NAME);
  // `add()` resolves on the NEXT tick, so an init-then-immediate-destroy would
@@ -526,12 +528,15 @@ function cesiumDrawSurface(viewer, live) {
  });
  return {
    canvas: viewer.scene.canvas,
-    /** The world point under a canvas position, or null. */
+    /** The world point under a canvas position (the engine's picks), or null. */
    pick(position) {
-      const canvas = viewer.scene.canvas;
-      const w = canvas.clientWidth || canvas.width || 1;
-      const h = canvas.clientHeight || canvas.height || 1;
-      return pickWorldFromScreen(viewer, position.x / w, position.y / h);
+      if (!engine) return null;
+      const { width, height } = engine.host.size();
+      return pickWorldFromScreen(
+        engine,
+        position.x / (width || 1),
+        position.y / (height || 1),
+      );
    },
    /** Show the open shape (null: none) in `color`. */
    sync(session, color) {
@@ -657,8 +662,8 @@ function cesiumDrawSurface(viewer, live) {
 * The Draw control for the page session. The marks live on the annotation
 * board and the chosen shape and colour here; the drawing tool itself (its
 * preview, click handler and Escape/Enter keys) belongs to the attached
- * globe. `attachScene({ viewer, navigation })` starts the tool on a Cesium
- * viewer, `attachScene({ surface, navigation })` on a globe without one
+ * globe. `attachScene({ viewer, engine, navigation })` starts the tool on
+ * a Cesium viewer, `attachScene({ surface, navigation })` on a globe without one
 * (Navara: src/annotations/drawInputNavara.js), with the shape and colour
 * last chosen; `detachScene()` ends it, an open shape included. Without a
 * globe the controls answer nothing. Same handle as initDrawTool's
@@ -731,6 +736,7 @@ export function createSessionDrawTool({
    whenSettled: () => inner?.whenSettled() ?? settled,
    attachScene({
      viewer = null,
+      engine = null,
      surface = null,
      navigation: next = navigation,
    } = {}) {
@@ -740,6 +746,7 @@ export function createSessionDrawTool({
      if (!viewer && !surface) return;
      inner = initDrawTool({
        viewer,
+        engine,
        surface,
        annotations,
        navigation,
@@ -53,7 +53,7 @@ test('the engine resolves manual geometry before any name resolution', () => {
    'async function resolveSpec(spec, signal) {',
  );
  const manualAt = engine.indexOf(
-    'if (isManualSpec(spec, type)) return resolveManualSpec(spec, type, viewer);',
+    'if (isManualSpec(spec, type)) return resolveManualSpec(spec, type, globe);',
    resolveAt,
  );
  const routeAt = engine.indexOf("if (type === 'route') {", resolveAt);
@@ -24,9 +24,10 @@ import { createScreenAnnotationRenderer } from './screenAnnotationRenderer.js';
 */
 export function createHybridAnnotationRenderer(
  viewer,
-  { screen: screenOptions, world: worldRenderer, screenScene } = {},
+  { screen: screenOptions, world: worldRenderer, screenScene, engine } = {},
 ) {
-  const world = worldRenderer ?? createWorldAnnotationRenderer(viewer);
+  const world =
+    worldRenderer ?? createWorldAnnotationRenderer(viewer, { engine });
  const screen = createScreenAnnotationRenderer(
    screenScene ?? viewer,
    screenOptions,
@@ -5,11 +5,18 @@ import { createPinia } from 'pinia';
 import { useScreenAnnotationsStore } from '../ui/stores/screenAnnotations.js';
 import { createHybridAnnotationRenderer } from './hybridAnnotationRenderer.js';
 import { showOsmCredit, hideOsmCredit } from '../data/dataCredits.js';
+import { createCesiumCredits } from '../globe/cesium/credits.js';
+
+/** The engine fakeViewer built for each viewer double (its credits). */
+const enginesOf = new WeakMap();

 /** A hybrid renderer whose screen board is presented to its own store. */
 function hybridWithBoard(viewer) {
  const store = useScreenAnnotationsStore(createPinia());
-  const renderer = createHybridAnnotationRenderer(viewer, { screen: { store } });
+  const renderer = createHybridAnnotationRenderer(viewer, {
+    screen: { store },
+    engine: enginesOf.get(viewer),
+  });
  return { store, renderer };
 }

@@ -107,10 +114,7 @@ function fakeViewer(lon, lat) {
      scene.renderRequests += 1;
    },
  };
-  return {
-    dataSources,
-    frames,
-    viewer: {
+  const viewer = {
      credits,
      creditDisplay: {
        addStaticCredit: (credit) => credits.add(credit),
@@ -130,8 +134,14 @@ function fakeViewer(lon, lat) {
          return index >= 0;
        },
      },
-    },
+    };
+  // The Cesium engine's credits over the viewer's credit display.
+  const engine = {
+    credits: createCesiumCredits(viewer).credits,
+    render: { request: () => scene.requestRender() },
  };
+  enginesOf.set(viewer, engine);
+  return { dataSources, frames, viewer, engine };
 }

 function controlledFrames() {
@@ -475,14 +485,14 @@ function workTrace() {

 test('buildings share one probe per frame and preserve probe geometry, filtering and fallback', async (t) => {
  installBrowserGlobals(t);
-  const { viewer, dataSources, frames } = fakeViewer(-99, 31);
-  const renderer = createHybridAnnotationRenderer(viewer);
+  const { viewer, engine, dataSources, frames } = fakeViewer(-99, 31);
+  const renderer = createHybridAnnotationRenderer(viewer, { engine });
  t.after(() => renderer.destroy());
  const first = buildingAnnotation('sampled-building');
  const second = buildingAnnotation('fallback-building', 0.01);
  second.outlineCredit = 'osm';
  const otherOwner = {};
-  showOsmCredit(viewer, otherOwner);
+  showOsmCredit(engine, otherOwner);
  const probes = [];
  const outcomes = [-500, 120, 30, null, new Error('tile unavailable'), 60, 9001, 90];
  viewer.scene.clampToHeight = (position) => {
@@ -583,7 +593,7 @@ test('buildings share one probe per frame and preserve probe geometry, filtering
    'removing the last tile proxy retains the OSM building and other owner');
  renderer.remove(second);
  assert.equal([...viewer.credits].filter(c => c.showOnScreen).length, 1);
-  hideOsmCredit(viewer, otherOwner);
+  hideOsmCredit(engine, otherOwner);
  assert.equal(viewer.credits.size, 0);
 });

@@ -12,22 +12,25 @@ import { createHybridAnnotationRenderer } from './hybridAnnotationRenderer.js';
 */
 export function initAnnotations({
  viewer,
+  engine: globe = null,
  tileset = null,
  placeSearch,
  resolver,
 }) {
  const engine = createSessionAnnotations({ placeSearch, resolver });
-  engine.attachScene({ viewer, tileset });
+  engine.attachScene({ viewer, engine: globe, tileset });
  return engine;
 }

 /**
 * The page's annotation board, kept across globe engine switches: the marks
- * belong to the page session, their drawing to the attached globe.
- * `attachScene({ viewer, tileset })` draws the board on a Cesium viewer;
- * `attachScene({ engine, renderer })` on a globe engine without a viewer
- * (Navara: src/annotations/navaraAnnotationRenderer.js, built by the caller
- * so this module never loads it); with neither the marks stay undrawn.
+ * belong to the page session, their drawing to the attached globe. The board
+ * works on the globe `engine` (camera, picks, surface); its drawing is the
+ * `renderer` built for that engine (Navara:
+ * src/annotations/navaraAnnotationRenderer.js, built by the caller so this
+ * module never loads it), or on a Cesium `viewer` the hybrid renderer built
+ * here. `attachScene({ engine, viewer, tileset })` or
+ * `attachScene({ engine, renderer })`; with neither the marks stay undrawn.
 * `detachScene()` releases the drawing and keeps the marks.
 */
 export function createSessionAnnotations({ placeSearch, resolver }) {
@@ -41,8 +44,7 @@ export function createSessionAnnotations({ placeSearch, resolver }) {
    engine: globe = null,
    renderer = null,
  } = {}) => {
-    if (!viewer && globe && renderer)
-      return engine.attachRenderer({ viewer: globe, renderer });
+    if (renderer) return engine.attachRenderer({ engine: globe, renderer });
    if (!viewer) return engine.detachRenderer();
    // World-space footprint draping; clamped marks can use the photoreal tiles.
    if (tileset) {
@@ -53,8 +55,8 @@ export function createSessionAnnotations({ placeSearch, resolver }) {
      }
    }
    engine.attachRenderer({
-      viewer,
-      renderer: createHybridAnnotationRenderer(viewer),
+      engine: globe,
+      renderer: createHybridAnnotationRenderer(viewer, { engine: globe }),
    });
  };
  engine.detachScene = () => engine.detachRenderer();
@@ -52,7 +52,7 @@ test('outlines sharing an outer ring but not their holes stay two marks', async
    footprintKind: 'area',
  });
  const engine = createAnnotationEngine({
-    viewer: {},
+    globe: {},
    renderer,
    resolveTarget,
  });
@@ -108,7 +108,7 @@ test('the engine resolves a bare street highlight with its footprint', async (t)
    };
  };
  const engine = createAnnotationEngine({
-    viewer: {},
+    globe: {},
    renderer,
    resolveTarget,
  });
@@ -138,7 +138,7 @@ test('a duplicate that fails to clean up never costs the new outline', async (t)
  const stuck = new Set();
  const outcomes = [];
  const engine = createAnnotationEngine({
-    viewer: {},
+    globe: {},
    renderer: {
      ...renderer,
      add(anno) {
@@ -28,6 +28,7 @@ import {
  createNominatimGate,
 } from '../../server/providers/regional/nominatimGate.js';
 import { createVoiceAreas } from '../voice/areaActions.js';
+import { cameraOnlyEngine } from '../testSupport/viewerEngine.mjs';

 const TILES = [6745, 6746].map((y) =>
  decodeOpenFreeMapOutlineTile(
@@ -924,15 +925,16 @@ const PLACES = {
  },
 };

-const viewerAt = (lat, lon, height = 4000) => ({
-  camera: {
-    positionCartographic: {
-      latitude: (lat * Math.PI) / 180,
-      longitude: (lon * Math.PI) / 180,
-      height,
+const viewerAt = (lat, lon, height = 4000) =>
+  cameraOnlyEngine({
+    camera: {
+      positionCartographic: {
+        latitude: (lat * Math.PI) / 180,
+        longitude: (lon * Math.PI) / 180,
+        height,
+      },
    },
-  },
-});
+  });

 test('default settings: outline, street and building asks send nothing to Overpass', async (t) => {
  const prior = process.env.OVERPASS_UPSTREAMS;
@@ -979,9 +981,9 @@ test('default settings: outline, street and building asks send nothing to Overpa
  const placeSearch = {
    geocode: async (q) => ({ place: PLACES[q] || null, answered: true }),
  };
-  const resolve = async (viewer, args) => {
+  const resolve = async (engine, args) => {
    const result = await resolver.resolveAnnotationTarget({
-      viewer,
+      engine,
      placeSearch,
      footprint: true,
      deferFootprint: true,
@@ -1000,7 +1002,7 @@ test('default settings: outline, street and building asks send nothing to Overpa
  });

  const areas = createVoiceAreas({
-    viewer: viewerAt(27.7, 85.3, 40_000),
+    engine: viewerAt(27.7, 85.3, 40_000),
    annotationResolver: resolver,
    placeSearch,
  });
@@ -7,9 +7,10 @@ import { FEATURE_SOURCE_METHODS } from '../sources/featureSource.js';
 import { createAnnotationResolver } from './resolver.js';
 import { polygonsContain } from '../data/adminBoundaries.js';
 import { streetFootprint } from './outlineRungs.js';
+import { cameraOnlyEngine } from '../testSupport/viewerEngine.mjs';

 function viewerAt(lat, lon, height = 20_000) {
-  return {
+  return cameraOnlyEngine({
    camera: {
      positionCartographic: {
        latitude: (lat * Math.PI) / 180,
@@ -17,7 +18,7 @@ function viewerAt(lat, lon, height = 20_000) {
        height,
      },
    },
-  };
+  });
 }

 /** A resolver whose boundary lookups and geocoder record every call. */
@@ -47,7 +48,7 @@ function harness(place = null, { outlineRungs } = {}) {
  const resolve = (target, viewer, extra = {}) =>
    resolveAnnotationTarget({
      placeSearch,
-      viewer,
+      engine: viewer,
      target,
      footprint: true,
      deferFootprint: true,
@@ -710,7 +711,7 @@ test('configured OSM geometry retains its origin through inline, deferred and ca
  });
  for (const deferFootprint of [false, true]) {
    const result = await resolver.resolveAnnotationTarget({
-      viewer: viewerAt(31, -99, 3000),
+      engine: viewerAt(31, -99, 3000),
      latitude: 31,
      longitude: -99,
      target: 'Library',
@@ -14,7 +14,6 @@ import {
  nearestPointOnLines,
 } from '../sources/featureGeometry.js';
 import { defaultGeospatial } from '../search/defaults.js';
-import * as Cesium from 'cesium';
 import * as geo from '../geo/index.js';
 import { lookupNeighborhoodRing } from '../data/neighborhoodPolygons.js';
 import {
@@ -46,7 +45,6 @@ import {
 import { createOutlineRungs } from './outlineRungs.js';
 import { unavailablePlaceSearch } from '../search/placeSearch.js';
 import { isPickedWorldPosition } from '../data/scenePick.js';
-import { isGlobeEngine } from '../globe/contract.js';

 /** Prepare only local dateline outlines for planar admission and centering. */
 function localOutlineFrame(fp) {
@@ -180,7 +178,8 @@ export function createAnnotationResolver({
   * Resolve a single annotation target to a normalized world anchor.
   *
   * @param {object} opts
-   * @param {Cesium.Viewer} opts.viewer
+   * @param {object} [opts.engine]  The globe engine (view bias, screen picks,
+   *                                    ground heights, credits).
   * @param {string} [opts.target]      Place name to geocode.
   * @param {number} [opts.latitude]    Explicit latitude (wins over target).
   * @param {number} [opts.longitude]   Explicit longitude.
@@ -202,7 +201,7 @@ export function createAnnotationResolver({
   */
  async function resolveAnnotationTarget({
    placeSearch = unavailablePlaceSearch,
-    viewer,
+    engine,
    target,
    latitude,
    longitude,
@@ -273,7 +272,7 @@ export function createAnnotationResolver({
      !NON_ADMIN_ENTITY_KINDS.has(entityKind)
    ) {
      const center =
-        pickWorldFromScreen(viewer, 0.5, 0.5) || viewportProximity(viewer);
+        pickWorldFromScreen(engine, 0.5, 0.5) || viewportProximity(engine);
      bundledCenter = center;
      const admin = await findAdminArea(trace.query, { near: center }).catch(
        () => null,
@@ -282,7 +281,7 @@ export function createAnnotationResolver({
      if (admin && !askNamesAdmin && isCoarseCityShape(admin))
        coarseCityShape = admin;
      else if (admin)
-        return bundledAdminTarget(viewer, admin, trace.query, signal);
+        return bundledAdminTarget(engine, admin, trace.query, signal);
      // Bundled US places and neighborhoods named at or near the view. A
      // campus, grounds or monument ask ("Stanford" as a compound, "the
      // Capitol grounds") wants that feature, not a district of its name,
@@ -290,10 +289,10 @@ export function createAnnotationResolver({
      if (intent !== 'around_the_thing' && !isMonumentLikeQuery(trace.query)) {
        const area = await bundledAreaNear(trace.query, center, {
          entityKind,
-          viewRadiusKm: viewportProximity(viewer)?.radiusKm ?? null,
+          viewRadiusKm: viewportProximity(engine)?.radiusKm ?? null,
        });
        signal?.throwIfAborted();
-        if (area) return bundledAdminTarget(viewer, area, trace.query, signal);
+        if (area) return bundledAdminTarget(engine, area, trace.query, signal);
      }
    }

@@ -301,7 +300,7 @@ export function createAnnotationResolver({
      const query = String(target || '').trim();
      if (query) {
        const center =
-          pickWorldFromScreen(viewer, 0.5, 0.5) || viewportProximity(viewer);
+          pickWorldFromScreen(engine, 0.5, 0.5) || viewportProximity(engine);
        // Monument / grounds names scatter under Geocoding — try a view-biased Places Text Search FIRST.
        // A hit near the view centre is trusted (skips the proximity gate, like the osm-local snap); on a
        // miss we fall through to geocode + fetchLocalMonument below. The model's entityKind counts too:
@@ -338,7 +337,7 @@ export function createAnnotationResolver({
        if (source !== 'places') {
          const geocoded = await geocodePlace(
            query,
-            viewportBias(viewer),
+            viewportBias(engine),
            signal,
            placeSearch,
          );
@@ -411,7 +410,7 @@ export function createAnnotationResolver({
      Number.isFinite(Number(screenY))
    ) {
      const picked = pickWorldFromScreen(
-        viewer,
+        engine,
        Number(screenX),
        Number(screenY),
      );
@@ -424,7 +423,7 @@ export function createAnnotationResolver({

    if (!Number.isFinite(lat) || !Number.isFinite(lon))
      return coarseCityHolds(bundledCenter)
-        ? bundledAdminTarget(viewer, coarseCityShape, trace.query, signal)
+        ? bundledAdminTarget(engine, coarseCityShape, trace.query, signal)
        : null;

    // Monument/memorial/statue names geocode unreliably — Google scatters them across the city (e.g.
@@ -437,7 +436,7 @@ export function createAnnotationResolver({
      (isMonumentLikeQuery(target) || entityKind === 'point_feature')
    ) {
      const center =
-        pickWorldFromScreen(viewer, 0.5, 0.5) || viewportProximity(viewer);
+        pickWorldFromScreen(engine, 0.5, 0.5) || viewportProximity(engine);
      if (center) {
        const mon = await fetchLocalMonument(
          center.lat,
@@ -470,7 +469,7 @@ export function createAnnotationResolver({
    // footprint resolution below re-checks its own recentered centroid against the same bound — a
    // polygon that would drag a good anchor out of plausibility is dropped (the mark stays an
    // honest point) rather than rejecting the whole annotation.
-    const vpGate = viewportProximity(viewer);
+    const vpGate = viewportProximity(engine);
    const gateDrift = (gLat, gLon) => {
      if (!vpGate) return null; // no camera info → pass
      const driftKm =
@@ -491,7 +490,7 @@ export function createAnnotationResolver({
          );
        }
        return coarseCityHolds(bundledCenter)
-          ? bundledAdminTarget(viewer, coarseCityShape, trace.query, signal)
+          ? bundledAdminTarget(engine, coarseCityShape, trace.query, signal)
          : null;
      }
    }
@@ -581,7 +580,7 @@ export function createAnnotationResolver({
        );
        signal?.throwIfAborted();
        if (ne) {
-          registerDynamicCredit(viewer, NATURAL_EARTH_CREDIT);
+          registerDynamicCredit(engine, NATURAL_EARTH_CREDIT);
          traceBundledOutline(ne.name, 'natural-earth');
          const neCentroid = ringCentroid(ne.ring);
          return {
@@ -594,7 +593,7 @@ export function createAnnotationResolver({
            lat: neCentroid?.lat ?? lat,
            lon: neCentroid?.lon ?? lon,
            height: sampleGroundHeight(
-              viewer,
+              engine,
              neCentroid?.lon ?? lon,
              neCentroid?.lat ?? lat,
            ),
@@ -642,7 +641,7 @@ export function createAnnotationResolver({
          signal?.throwIfAborted();
          if (admin && !askNamesAdmin && isCoarseCityShape(admin))
            coarseCityShape ||= admin;
-          else if (admin) return bundledAdminOutline(viewer, admin, signal);
+          else if (admin) return bundledAdminOutline(engine, admin, signal);
        }
        // A geocoded US city, town or CDP: the Census place that holds it.
        if (scope === 'city') {
@@ -652,7 +651,7 @@ export function createAnnotationResolver({
            lon,
          ).catch(() => null);
          signal?.throwIfAborted();
-          if (place) return bundledAdminOutline(viewer, place, signal);
+          if (place) return bundledAdminOutline(engine, place, signal);
        }
        // Pure admin: only an admin boundary is correct — never fall back to a
        // building/landuse (a city is never a single building).
@@ -676,7 +675,7 @@ export function createAnnotationResolver({
            lon,
          ).catch(() => null);
          signal?.throwIfAborted();
-          if (wof) return bundledAdminOutline(viewer, wof, signal);
+          if (wof) return bundledAdminOutline(engine, wof, signal);
        }
        // Else fall through to the OSM admin/place → named-landuse → synthesis ladder. Each
        // returns a footprint, null (definitively no polygon), or undefined (transient
@@ -875,7 +874,7 @@ export function createAnnotationResolver({
        ...(fp.adminLevel ? { adminLevel: fp.adminLevel } : {}),
        lat: centroid.lat,
        lon: centroid.lon,
-        height: sampleGroundHeight(viewer, centroid.lon, centroid.lat),
+        height: sampleGroundHeight(engine, centroid.lon, centroid.lat),
      };
    };

@@ -891,11 +890,11 @@ export function createAnnotationResolver({
      pointLike,
      groundsLike,
      around: intent === 'around_the_thing',
-      view: viewportProximity(viewer),
+      view: viewportProximity(engine),
      signal,
      credit: (kind) =>
        registerDynamicCredit(
-          viewer,
+          engine,
          kind === 'tiles' ? OPENMAPTILES_CREDIT : OSM_CREDIT,
        ),
    };
@@ -911,7 +910,7 @@ export function createAnnotationResolver({
        coarseCityHolds({ lat, lon }) &&
        !(result?.ring && !result.synthesized)
      )
-        return bundledAdminOutline(viewer, coarseCityShape, signal);
+        return bundledAdminOutline(engine, coarseCityShape, signal);
      return result;
    };

@@ -939,7 +938,7 @@ export function createAnnotationResolver({
      }
    }

-    const height = sampleGroundHeight(viewer, lon, lat);
+    const height = sampleGroundHeight(engine, lon, lat);
    // One concise line per target so the resolution path is visible in the browser console.
    if (trace.query) {
      console.log(
@@ -1004,13 +1003,13 @@ export function createAnnotationResolver({
  const COARSE_CITY_MAX_VERTICES = 32;

  /** Credit the pack a bundled boundary came from. */
-  function creditAdminSource(viewer, admin) {
+  function creditAdminSource(engine, admin) {
    const credit = {
      'natural-earth': NATURAL_EARTH_CREDIT,
      'us-census': US_CENSUS_CREDIT,
      wof: WOF_CREDIT,
    }[admin.source];
-    if (credit) registerDynamicCredit(viewer, credit);
+    if (credit) registerDynamicCredit(engine, credit);
  }

  /**
@@ -1113,9 +1112,9 @@ export function createAnnotationResolver({
   * draw them. Like the Natural Earth rung, it bypasses the scope caps and the
   * centroid drift bound: the unit IS the asked scope.
   */
-  function bundledAdminOutline(viewer, admin, signal) {
+  function bundledAdminOutline(engine, admin, signal) {
    signal?.throwIfAborted();
-    creditAdminSource(viewer, admin);
+    creditAdminSource(engine, admin);
    traceBundledOutline(admin.name, admin.source, admin.polygons?.length);
    const { lat, lon } = admin.label;
    return {
@@ -1128,7 +1127,7 @@ export function createAnnotationResolver({
      outlineSource: admin.source,
      lat,
      lon,
-      height: sampleGroundHeight(viewer, lon, lat),
+      height: sampleGroundHeight(engine, lon, lat),
    };
  }

@@ -1158,8 +1157,8 @@ export function createAnnotationResolver({
  }

  /** A complete resolved target for a bundled administrative unit (no outline pending). */
-  function bundledAdminTarget(viewer, admin, query, signal) {
-    const outline = bundledAdminOutline(viewer, admin, signal);
+  function bundledAdminTarget(engine, admin, query, signal) {
+    const outline = bundledAdminOutline(engine, admin, signal);
    const [west, south, east, north] = admin.bbox;
    console.log(
      `[Resolver] "${query}": bundled ${admin.kind} "${admin.name}"` +
@@ -2200,7 +2199,7 @@ export function createAnnotationResolver({
    return matches;
  }

-  // --- viewer helpers ---------------------------------------------------------
+  // --- engine helpers ---------------------------------------------------------

  /**
   * Current view rectangle as a Google `bounds` string `swLat,swLng|neLat,neLng`,
@@ -2216,12 +2215,9 @@ export function createAnnotationResolver({
   * Radius is scaled from camera height (a generous proxy for how much ground is on screen), with a
   * floor so a super-zoomed-in view doesn't over-reject genuinely nearby places.
   */
-  function viewportProximity(viewer) {
+  function viewportProximity(engine) {
    try {
-      // A globe engine (search) or a Cesium viewer (annotations until 1c).
-      const carto = isGlobeEngine(viewer)
-        ? viewer.camera.pose().cartographic
-        : viewer?.camera?.positionCartographic;
+      const carto = engine?.camera.pose().cartographic;
      if (!carto) return null;
      const lat = geo.math.toDegrees(carto.latitude);
      const lon = geo.math.toDegrees(carto.longitude);
@@ -2234,11 +2230,9 @@ export function createAnnotationResolver({
  }

  /** Exported for searchAndFlyTo (src/locations.js), which shares this bias. */
-  function viewportBias(viewer) {
+  function viewportBias(engine) {
    try {
-      const rect = isGlobeEngine(viewer)
-        ? viewer.camera.viewRectangle()
-        : viewer?.camera?.computeViewRectangle?.();
+      const rect = engine?.camera.viewRectangle();
      if (!rect) return null;
      const swLat = geo.math.toDegrees(rect.south).toFixed(4);
      const swLng = geo.math.toDegrees(rect.west).toFixed(4);
@@ -2262,14 +2256,14 @@ export function createAnnotationResolver({
   * ({ lat, lon, label, types, viewport, distanceM, … }) or null.
   */
  async function placesNearViewRecovery(
-    viewer,
+    engine,
    query,
    geocoded = null,
    signal = undefined,
    placeSearch = defaultGeospatial,
  ) {
    const center =
-      pickWorldFromScreen(viewer, 0.5, 0.5) || viewportProximity(viewer);
+      pickWorldFromScreen(engine, 0.5, 0.5) || viewportProximity(engine);
    if (!center) return null;
    const geocodeFar =
      !geocoded ||
@@ -2313,9 +2307,28 @@ export function createAnnotationResolver({
    return geo.cartesian3.distance(hit, camera) < Math.max(2, 0.01 * reference);
  }

-  /** pickWorldFromScreen through a globe engine: the same cascade. */
-  function enginePickWorldFromScreen(engine, nx, ny) {
-    const { width: w, height: h } = engine.host.size();
+  /**
+   * Convert a NORMALIZED screen point (x,y in [0,1] of the current viewport) into
+   * a world lon/lat using the depth-aware pick cascade — the inverse of the
+   * project-to-screen used by the renderers. This is the "point at the pixel"
+   * fallback: the agent indicates a spot in the viewport screenshot when it can't
+   * name the place, and we anchor the mark to the actual world point under it.
+   *
+   * Each stage is validated before it is accepted: a depth pick over empty sky
+   * can return a NaN or centre-of-the-earth Cartesian. A degenerate pick IS a
+   * missed pick, so it falls through to the next stage and ultimately to the
+   * caller's null. The answer carries the height the pick landed on (a roof, a
+   * hillside, or 0 on the ellipsoid): the draw tool's live preview needs it,
+   * or the rubber band sinks to sea level while the pointer is on a hill.
+   */
+  function pickWorldFromScreen(engine, nx, ny) {
+    let size;
+    try {
+      size = engine?.host.size();
+    } catch {
+      return null;
+    }
+    const { width: w, height: h } = size ?? {};
    if (!w || !h) return null;
    const screen = {
      x: Math.max(0, Math.min(1, nx)) * w,
@@ -2343,107 +2356,13 @@ export function createAnnotationResolver({
  }

  /**
-   * Convert a NORMALIZED screen point (x,y in [0,1] of the current viewport) into
-   * a world lon/lat using the depth-aware pick cascade — the inverse of the
-   * project-to-screen used by the renderers. This is the "point at the pixel"
-   * fallback: the agent indicates a spot in the viewport screenshot when it can't
-   * name the place, and we anchor the mark to the actual world point under it.
+   * Best-effort ground height at a coordinate. The globe is hidden behind
+   * the Google 3D tiles, so we try to clamp onto the rendered surface; if the
+   * tiles for that spot aren't loaded we fall back to the terrain, else the
+   * ellipsoid (0).
   */
-  function pickWorldFromScreen(viewer, nx, ny) {
-    if (isGlobeEngine(viewer)) return enginePickWorldFromScreen(viewer, nx, ny);
-    const scene = viewer?.scene;
-    if (!scene) return null;
-    const canvas = scene.canvas;
-    const w = canvas.clientWidth || canvas.width || 0;
-    const h = canvas.clientHeight || canvas.height || 0;
-    if (!w || !h) return null;
-    const px = Math.max(0, Math.min(1, nx)) * w;
-    const py = Math.max(0, Math.min(1, ny)) * h;
-    const pos = new Cesium.Cartesian2(px, py);
-
-    // Each stage is validated before it is accepted: a depth pick over empty sky
-    // can return a NaN or centre-of-the-earth Cartesian, and converting one of
-    // those throws inside Cesium. A degenerate pick IS a missed pick, so it falls
-    // through to the next stage and ultimately to the caller's null.
-    let cart = null;
-    if (
-      scene.pickPositionSupported &&
-      typeof scene.pickPosition === 'function'
-    ) {
-      try {
-        cart = scene.pickPosition(pos);
-      } catch {
-        cart = null;
-      }
-    }
-    if (
-      !isPickedWorldPosition(cart) &&
-      typeof viewer.camera.pickEllipsoid === 'function'
-    ) {
-      try {
-        cart = viewer.camera.pickEllipsoid(pos, Cesium.Ellipsoid.WGS84);
-      } catch {
-        cart = null;
-      }
-    }
-    if (
-      !isPickedWorldPosition(cart) &&
-      typeof viewer.camera.getPickRay === 'function'
-    ) {
-      try {
-        const ray = viewer.camera.getPickRay(pos);
-        cart = ray ? scene.globe?.pick(ray, scene) || null : null;
-      } catch {
-        cart = null;
-      }
-    }
-    if (!isPickedWorldPosition(cart)) return null;
-    const carto = geo.cartographic.fromCartesian(cart);
-    if (!carto) return null;
-    return {
-      lat: geo.math.toDegrees(carto.latitude),
-      lon: geo.math.toDegrees(carto.longitude),
-      // The height the pick actually landed on — a roof, a hillside, or 0 on
-      // the ellipsoid. Callers that only want a coordinate ignore it; the draw
-      // tool's live preview needs it, or the rubber band sinks to sea level
-      // while the pointer is on a hill.
-      height: Number.isFinite(carto.height) ? carto.height : 0,
-    };
-  }
-
-  /**
-   * Best-effort ground height at a coordinate. The Cesium globe is hidden behind
-   * the Google 3D tiles, so we try to clamp onto the photoreal tile surface; if
-   * the tiles for that spot aren't loaded we fall back to the ellipsoid (0).
-   */
-  function sampleGroundHeight(viewer, lon, lat) {
-    if (isGlobeEngine(viewer)) return engineGroundHeight(viewer, lon, lat);
-    const scene = viewer?.scene;
-    if (!scene) return 0;
-    try {
-      if (
-        scene.clampToHeightSupported &&
-        typeof scene.clampToHeight === 'function'
-      ) {
-        const carto = geo.cartographic.fromDegrees(lon, lat);
-        const surface = geo.cartographic.toCartesian(carto);
-        const clamped = scene.clampToHeight(surface);
-        if (clamped) {
-          const h = geo.cartographic.fromCartesian(clamped).height;
-          if (Number.isFinite(h)) return h;
-        }
-      }
-    } catch {
-      /* tiles not ready — fall through */
-    }
-    const globeHeight = scene.globe?.getHeight?.(
-      geo.cartographic.fromDegrees(lon, lat),
-    );
-    return Number.isFinite(globeHeight) && globeHeight > 0 ? globeHeight : 0;
-  }
-
-  /** sampleGroundHeight on a globe engine: the rendered surface, else terrain. */
-  function engineGroundHeight(engine, lon, lat) {
+  function sampleGroundHeight(engine, lon, lat) {
+    if (!engine) return 0;
    try {
      if (engine.surface.clampToHeightSupported) {
        const clamped = engine.surface.clampToHeight(
@@ -1,6 +1,5 @@
-// The view-centred search helpers read the camera through a globe engine as
-// well as through a viewer (src/locations.js searchAndFlyTo hands them the
-// engine).
+// The view-centred search helpers read the camera through the globe engine
+// (src/locations.js searchAndFlyTo and the annotation board hand it to them).
 import test from 'node:test';
 import assert from 'node:assert/strict';
 import * as geo from '../geo/index.js';
@@ -47,7 +47,12 @@ const PALETTE = {
 * BOTH paints onto terrain AND onto 3D tiles, so one value covers both worlds.
 */

-export function createWorldAnnotationRenderer(viewer) {
+/**
+ * @param {Cesium.Viewer} viewer
+ * @param {{ engine?: object }} [options] `engine`: the globe engine whose
+ *   credits show the OpenStreetMap attribution of the marks drawn from it.
+ */
+export function createWorldAnnotationRenderer(viewer, { engine = null } = {}) {
  const CLASSIFY = Cesium.ClassificationType.BOTH;
  const CLAMP = Cesium.HeightReference.CLAMP_TO_GROUND;
  const dataSource = new Cesium.CustomDataSource('gev-annotations');
@@ -522,7 +527,7 @@ export function createWorldAnnotationRenderer(viewer) {
        }),
      );
      osmAnnotations.add(anno);
-      showOsmCredit(viewer, anno);
+      showOsmCredit(engine, anno);
    } else if (anno.type === 'arrow' && anno.to) {
      // Connector draped across the ground from origin to destination.
      const positions = [
@@ -577,7 +582,7 @@ export function createWorldAnnotationRenderer(viewer) {
    ) {
      // The actual world proxy owns both geometry and credit, including rollback.
      osmAnnotations.add(anno);
-      showOsmCredit(viewer, anno, {
+      showOsmCredit(engine, anno, {
        openMapTiles: anno.outlineCredit === 'tiles',
      });
    }
@@ -600,7 +605,7 @@ export function createWorldAnnotationRenderer(viewer) {

  function remove(anno) {
    pendingGround.get(anno)?.finish('cancelled');
-    hideOsmCredit(viewer, anno);
+    hideOsmCredit(engine, anno);
    osmAnnotations.delete(anno);
    drawn.delete(anno);
    if (!anno?._entities) return;
@@ -630,7 +635,7 @@ export function createWorldAnnotationRenderer(viewer) {
  function destroy() {
    destroyed = true;
    for (const task of [...pendingGround.values()]) task.finish('cancelled');
-    for (const anno of osmAnnotations) hideOsmCredit(viewer, anno);
+    for (const anno of osmAnnotations) hideOsmCredit(engine, anno);
    osmAnnotations.clear();
    drawn.clear();
    try {
@@ -13,11 +13,11 @@ import {
 } from './layers/renderers.js';
 import {
  governorRequestRender,
-  installRenderGovernor,
+  installEngineRenderGovernor,
  uninstallRenderGovernor,
 } from '../renderGovernor.js';
 import { attachSessionVoice } from './sessionVoice.js';
-import { initNavaraImageryBoxTool } from '../ui/imageryBoxNavara.js';
+import { initImageryBoxTool } from '../ui/imageryBoxTool.js';
 import {
  attachNavaraAnnotations,
  attachNavaraDraw,
@@ -368,7 +368,7 @@ export function attachViewerlessTools(
  });
  const recentImagery = dataManager.layers.get('recent-imagery')?.module;
  if (recentImagery) {
-    const tool = initNavaraImageryBoxTool({
+    const tool = initImageryBoxTool({
      engine,
      onBox: (box) => recentImagery.setBox(box),
      onPreview: (box) => recentImagery.setBoxPreview(box),
@@ -397,7 +397,7 @@ export function attachViewerlessTools(
  }
  // Holds drive engine.render.setContinuous; requests go to the engine. A
  // parked engine uninstalls it (createNavaraScene suspend).
-  installRenderGovernor(engine);
+  installEngineRenderGovernor(engine);
  const syncVisibility = () => {
    if (document.hidden && !isEmbeddedInline()) return;
    data.presentation.flushVisible();
@@ -3,7 +3,7 @@ import assert from 'node:assert/strict';
 import { createApplicationScene } from './scene.js';
 import { createFakeEngine } from '../globe/testing/fakeEngine.js';
 import {
-  installRenderGovernor,
+  installEngineRenderGovernor,
  isRenderGovernorInstalled,
 } from '../renderGovernor.js';

@@ -164,7 +164,7 @@ test('the Navara scene tears down the controller, then the globe', async (t) =>
  const run = await startScene();
  // The tools install the governor on the engine (src/app/tools.js); the
  // scene removes it before the engine goes.
-  installRenderGovernor(run.engine);
+  installEngineRenderGovernor(run.engine);
  const view = globalThis.window;
  await run.teardown();
  assert.equal(run.globeDestroyed(), 1);
@@ -275,7 +275,7 @@ function attachViewerTools(
    resolver: operations.annotationResolver,
    defer,
  });
-  annotations.attachScene({ viewer, tileset });
+  annotations.attachScene({ viewer, engine, tileset });
  defer(() => annotations.detachScene());
  // UTILITIES ▸ Draw on this viewer (src/app/sessionTools.js): the tool
  // claims this viewer's pointer while a sketch is open.
@@ -285,7 +285,7 @@ function attachViewerTools(
    styleManager,
    defer,
  });
-  drawTool?.attachScene({ viewer, navigation: styleManager });
+  drawTool?.attachScene({ viewer, engine, navigation: styleManager });
  defer(() => drawTool?.detachScene());
  // UTILITIES ▸ Import on this viewer: the next Cesium viewer reads the
  // session's files again. The drop listeners belong to this viewer.
@@ -309,8 +309,9 @@ function attachViewerTools(
  if (recentImagery) {
    recentImagery.attachTileset(tileset);
    const imageryBoxTool = initImageryBoxTool({
-      viewer,
+      engine,
      onBox: (box) => recentImagery.setBox(box),
+      onPreview: (box) => recentImagery.setBoxPreview(box),
      onCancel: (reason, message, box) => {
        if (message) recentImagery.reportBoxRefusal(message, box);
      },
@@ -6,6 +6,16 @@ import {
  globeOutOfFrame,
 } from '../globeInView.js';

+// Dev convenience: expose the app's Cesium instance for console/preview probing
+// (single shared module instance — avoids dual-Cesium state bugs when testing).
+// A getter, because the production build's Cesium global loads only with the
+// first Cesium globe.
+if (typeof window !== 'undefined' && !('__CESIUM__' in window))
+  Object.defineProperty(window, '__CESIUM__', {
+    configurable: true,
+    get: () => Cesium,
+  });
+
 const PINCH_ZOOM_MULTIPLIER = 8;
 const MAX_PINCH_PIXEL_DELTA = 120;

@@ -3569,7 +3569,7 @@ export function createBhoteKoshiEventLayer({
      else await _viewer.dataSources.add(_floodDataSource);
      if (!current()) return;
    }
-    registerDynamicCredit(engine ?? viewer, BHOTE_KOSHI_CREDIT);
+    registerDynamicCredit(engine, BHOTE_KOSHI_CREDIT);
    _scenePathPositionCache.clear();
    _lastCinematicProgress = null;
    const terrain = syncTerrainComparison();
@@ -3640,7 +3640,7 @@ export function createBhoteKoshiEventLayer({
    try {
      const event = await loadEvent();
      throwIfEnableCancelled(signal, _enabled);
-      registerDynamicCredit(_engine ?? viewer, BHOTE_KOSHI_CREDIT);
+      registerDynamicCredit(_engine, BHOTE_KOSHI_CREDIT);
      if (_mapStackController) {
        _comparisonLease = acquireImageryComparison(_mapStackController, {
          owner: BHOTE_KOSHI_LAYER_ID,
@@ -291,7 +291,6 @@ export function createBhoteKoshiLocatorLayer({
  let _native = null;
  let _pausedApproach = null;
  const cameraForScene = () => _engine?.camera ?? _viewer?.camera;
-  const creditTarget = () => _engine ?? _viewer;
  const requestRender = (reason) =>
    _engine?.kind === 'navara'
      ? _engine.render.request(reason)
@@ -1049,8 +1048,8 @@ export function createBhoteKoshiLocatorLayer({
    if (!_dataSource) return;
    if (_viewer) _viewer.dataSources.add(_dataSource);
    else if (_engine) _native = createNativeRenderer(_engine, _dataSource);
-    registerDynamicCredit(creditTarget(), BHOTE_KOSHI_LOCATOR_CREDIT);
-    showOsmCredit(creditTarget(), BHOTE_KOSHI_LOCATOR_LAYER_ID);
+    registerDynamicCredit(_engine, BHOTE_KOSHI_LOCATOR_CREDIT);
+    showOsmCredit(_engine, BHOTE_KOSHI_LOCATOR_LAYER_ID);
  }

  function attachRenderer(viewer, { engine = null } = {}) {
@@ -1080,7 +1079,7 @@ export function createBhoteKoshiLocatorLayer({
    _native?.destroy();
    _native = null;
    if (_viewer && _dataSource) _viewer.dataSources.remove(_dataSource, false);
-    hideOsmCredit(creditTarget(), BHOTE_KOSHI_LOCATOR_LAYER_ID);
+    hideOsmCredit(_engine, BHOTE_KOSHI_LOCATOR_LAYER_ID);
    _engine = _viewer = null;
  }

@@ -1137,7 +1136,7 @@ export function createBhoteKoshiLocatorLayer({
  }

  async function disable() {
-    hideOsmCredit(creditTarget(), BHOTE_KOSHI_LOCATOR_LAYER_ID);
+    hideOsmCredit(_engine, BHOTE_KOSHI_LOCATOR_LAYER_ID);
    _pausedApproach = null;
    _enabled = false;
    _boundaryReady = false;
@@ -9,6 +9,7 @@ import * as Cesium from 'cesium';
 import { FEATURE_SOURCE_METHODS } from '../sources/featureSource.js';
 import { createAnnotationResolver } from '../annotations/resolver.js';
 import { createWorldAnnotationRenderer } from '../annotations/worldAnnotationRenderer.js';
+import { cameraOnlyEngine } from '../testSupport/viewerEngine.mjs';

 const read = (path) => readFileSync(new URL(path, import.meta.url), 'utf8');

@@ -135,8 +136,8 @@ test('drawing bundled place and neighborhood outlines creates no Cesium label',
      3000,
    );
    const resolved = await resolveAnnotationTarget({
-      // The resolver reads only the camera (no scene to pick from).
-      viewer: { camera: viewer.camera },
+      // The resolver reads only the camera (no canvas to pick from).
+      engine: cameraOnlyEngine({ camera: viewer.camera }),
      target,
      footprint: true,
      deferFootprint: true,
@@ -1,8 +1,5 @@
-import { isGlobeEngine } from '../globe/contract.js';
-import { createCesiumCredits } from '../globe/cesium/credits.js';
-
 /**
- * Per-layer data attribution registered into Cesium's credit display.
+ * Per-layer data attribution registered into the globe engine's credits.
 *
 * Legal requirement (see DATA_SOURCES.md, findings H10/H11 in
 * docs/pre-ship-audit-2026-07-01.md): every third-party data layer this app can
@@ -13,7 +10,7 @@ import { createCesiumCredits } from '../globe/cesium/credits.js';
 *
 * These credits are registered ONCE at init as STATIC credits with
 * showOnScreen=false, so they live in the expandable bottom-left "Data
- * attribution" lightbox (Cesium's credit popover) rather than cluttering the
+ * attribution" lightbox (the engine's credit popover) rather than cluttering the
 * on-globe line. Always-present is intentional and reversible: the lightbox is
 * the app's canonical attribution surface and DATA_SOURCES.md is the
 * machine-readable index. Strings are copied verbatim from DATA_SOURCES.md — if
@@ -49,29 +46,18 @@ export const ACARTIA_CREDIT = Object.freeze({

 const osmDisplays = new WeakMap();
 const googlePlacesDisplays = new WeakMap();
-const viewerCredits = new WeakMap();

 /**
- * Credits of a globe engine, or of a Cesium viewer's credit display for
- * callers that still hold a viewer (Cesium layers); null without one.
+ * Credits of a globe engine (engine.credits, shown on its next frame); null
+ * without one.
 * @returns {{ addStatic: Function, request: () => void } | null}
 */
-function creditsOf(target) {
-  if (isGlobeEngine(target))
-    return {
-      addStatic: (html, options) => target.credits.addStatic(html, options),
-      request: () => target.render.request('credits'),
-    };
-  if (typeof target?.creditDisplay?.addStaticCredit !== 'function') return null;
-  let credits = viewerCredits.get(target);
-  if (!credits) {
-    credits = {
-      addStatic: createCesiumCredits(target).credits.addStatic,
-      request: () => target.scene?.requestRender?.(),
-    };
-    viewerCredits.set(target, credits);
-  }
-  return credits;
+function creditsOf(engine) {
+  if (typeof engine?.credits?.addStatic !== 'function') return null;
+  return {
+    addStatic: (html, options) => engine.credits.addStatic(html, options),
+    request: () => engine.render?.request('credits'),
+  };
 }

 function updateOsmDisplay(credits, state) {
@@ -713,7 +699,7 @@ const dynamicCreditKeys = new WeakMap();
 * Register a conditional credit at the moment its data source activates.
 * Idempotent per `credit.key`; lands in the same "Data attribution" popover
 * as the static credits (showOnScreen=false).
- * @param {object} target — the globe engine, or the initialized Cesium viewer
+ * @param {object} target — the globe engine
 * @param {{ key: string, html: string }} credit — e.g. `TOMTOM_CREDIT`
 * @returns {boolean} True when the credit is (now) registered.
 */
@@ -730,10 +716,10 @@ export function registerDynamicCredit(target, credit) {
 }

 /**
- * Register every per-layer data credit into the viewer's credit display.
+ * Register every per-layer data credit into the engine's credit display.
 * Idempotent: safe to call once at init. Credits are static and always
 * present in the "Data attribution" popover.
- * @param {object} target — the globe engine, or the initialized Cesium viewer
+ * @param {object} target — the globe engine
 */
 export function registerDataCredits(target, credits = DATA_CREDITS) {
  const display = creditsOf(target);
@@ -56,17 +56,25 @@ test('OpenStreetMap has one generic data credit with separate tile and names dis
  );
 });

+// A Cesium engine's credits over a viewer double's credit display.
+async function cesiumCreditsEngine(viewer) {
+  const { createCesiumCredits } = await import('../globe/cesium/credits.js');
+  return {
+    credits: createCesiumCredits(viewer).credits,
+    render: { request() {} },
+  };
+}
+
 test('inline OSM attribution persists until its last display owner leaves', async (t) => {
  const { showOsmCredit, hideOsmCredit } = await import('./dataCredits.js');
  t.mock.timers.enable({ apis: ['setTimeout'] });
  const visible = new Set();
-  const viewer = {
+  const viewer = await cesiumCreditsEngine({
    creditDisplay: {
      addStaticCredit: (c) => visible.add(c),
      removeStaticCredit: (c) => visible.delete(c),
    },
-    scene: { requestRender() {} },
-  };
+  });
  assert.equal(showOsmCredit(viewer, 'alpr'), true);
  assert.equal(showOsmCredit(viewer, 'alpr'), false);
  assert.equal(visible.size, 1);
@@ -96,29 +104,31 @@ test('inline OSM attribution persists until its last display owner leaves', asyn
  assert.equal(visible.size, 1, 'reenabling restores the short credit');
 });

-test('tile attribution follows source changes and viewers have independent ownership', async () => {
+test('tile attribution follows source changes and engines have independent ownership', async () => {
  const { showOsmCredit, hideOsmCredit } = await import('./dataCredits.js');
-  const create = () => {
+  const create = async () => {
    const credits = new Set();
    return {
-      credits,
-      creditDisplay: {
-        addStaticCredit: (c) => credits.add(c),
-        removeStaticCredit: (c) => credits.delete(c),
-      },
+      shown: credits,
+      ...(await cesiumCreditsEngine({
+        creditDisplay: {
+          addStaticCredit: (c) => credits.add(c),
+          removeStaticCredit: (c) => credits.delete(c),
+        },
+      })),
    };
  };
-  const a = create(),
-    b = create();
+  const a = await create(),
+    b = await create();
  showOsmCredit(a, 'installations', { openMapTiles: true });
  showOsmCredit(b, 'installations');
-  assert.equal(a.credits.size, 2);
-  assert.equal(b.credits.size, 1);
+  assert.equal(a.shown.size, 2);
+  assert.equal(b.shown.size, 1);
  showOsmCredit(a, 'installations');
-  assert.equal(a.credits.size, 1, 'wide names no longer use tiles');
+  assert.equal(a.shown.size, 1, 'wide names no longer use tiles');
  hideOsmCredit(a, 'installations');
-  assert.equal(a.credits.size, 0);
-  assert.equal(b.credits.size, 1);
+  assert.equal(a.shown.size, 0);
+  assert.equal(b.shown.size, 1);
 });

 test('data credits go through the globe engine credits', async () => {
@@ -1,15 +1,13 @@
 import { worldToWindowCoordinates } from './render/cesiumProjection.js';
 import * as geo from '../geo/index.js';
-import { engineFromViewer } from '../globe/cesium/engineFromViewer.js';

-// A window position through the engine's projector when `scene` has a
-// registered engine (a Cesium scene in the app, the Navara aircraft
-// renderer's scene adapter), else Cesium's SceneTransforms (bare scenes in
-// tests). The two agree on Cesium (the engine projector is SceneTransforms).
+// A window position through the engine projector the scene carries (the
+// layers' engine views, src/layers/shared/render/engineView.js), else
+// Cesium's SceneTransforms (a Cesium scene). The two agree on Cesium (the
+// engine projector is SceneTransforms).
 function worldToWindow(scene, position, result) {
-  const projector = engineFromViewer(scene)?.projector;
-  return projector
-    ? projector.worldToWindow(position, result)
+  return scene.projector
+    ? scene.projector.worldToWindow(position, result)
    : worldToWindowCoordinates(scene, position, result);
 }

@@ -163,12 +163,9 @@ test('NearFarScalar rendered-size interpolation matches Cesium clamp endpoints',
  assert.ok(middle > 0.5 && middle < 3);
 });

-test('a focus target projects through the engine registered for its scene', async () => {
+test('a focus target projects through the projector its scene carries', async () => {
  const { publishFocusTargetFromCachedPosition, clearFocusTarget } =
    await import('./focusDeemphasis.js');
-  const { registerViewerEngine } = await import(
-    '../globe/cesium/engineFromViewer.js'
-  );
  const { createFakeEngine } = await import('../globe/testing/fakeEngine.js');
  const engine = createFakeEngine();
  const projected = [];
@@ -176,9 +173,11 @@ test('a focus target projects through the engine registered for its scene', asyn
    projected.push(position);
    return Object.assign(result, { x: 300, y: 200 });
  };
-  // A scene with no Cesium behind it (the Navara renderer's adapter).
-  const scene = { frameState: { frameNumber: 7 } };
-  const unregister = registerViewerEngine(scene, engine);
+  // A scene with no Cesium behind it (a layer's engine view).
+  const scene = {
+    frameState: { frameNumber: 7 },
+    projector: engine.projector,
+  };
  try {
    const target = publishFocusTargetFromCachedPosition({
      ownerLayer: 'flights',
@@ -201,7 +200,6 @@ test('a focus target projects through the engine registered for its scene', asyn
    assert.equal(target.frameNumber, 7);
  } finally {
    clearFocusTarget('flights');
-    unregister();
    engine.destroy();
  }
 });
@@ -26,14 +26,12 @@ import {
  horizonOccluder,
 } from './render/cesiumProjection.js';
 import * as geo from '../geo/index.js';
-import { engineFromViewer } from '../globe/cesium/engineFromViewer.js';

-// A window position through the engine's projector when `scene` has a
-// registered engine (engineFromViewer), else Cesium's SceneTransforms.
+// A window position through the engine projector the scene carries (the
+// layers' engine views), else Cesium's SceneTransforms (a Cesium scene).
 function worldToWindow(scene, position, result) {
-  const projector = engineFromViewer(scene)?.projector;
-  return projector
-    ? projector.worldToWindow(position, result)
+  return scene.projector
+    ? scene.projector.worldToWindow(position, result)
    : worldToWindowCoordinates(scene, position, result);
 }

@@ -746,13 +746,12 @@ test('the perspective helper is continuous through the sub-pixel band, not a 23
    );
 });

-test('the exact projection asks the engine projector of a registered scene', async () => {
+test('the exact projection asks the engine projector its scene carries', async () => {
  const geo = await import('../geo/index.js');
-  const { registerViewerEngine } = await import('../globe/cesium/engineFromViewer.js');
  const { perspectiveProjectedRotation: rotation } = await import('./iconOrientation.js');
-  const scene = { camera: { rightWC: { x: 0, y: 1, z: 0 }, upWC: { x: 0, y: 0, z: 1 } } };
  const asked = [];
-  const unregister = registerViewerEngine({ scene }, {
+  const scene = {
+    camera: { rightWC: { x: 0, y: 1, z: 0 }, upWC: { x: 0, y: 0, z: 1 } },
    projector: {
      // Screen-right for every point further east (the probe), so 90° on screen.
      worldToWindow(position, result = geo.cartesian2.create()) {
@@ -760,12 +759,8 @@ test('the exact projection asks the engine projector of a registered scene', asy
        return Object.assign(result, { x: asked.length === 1 ? 100 : 120, y: 100 });
      },
    },
-  });
-  try {
-    const value = rotation(scene, geo.cartesian3.fromDegrees(0, 0, 0), 90, null);
-    assert.equal(asked.length, 2, 'the anchor and the probe');
-    assert.ok(Math.abs(value - -Math.PI / 2) < 1e-9, `rotation ${value}`);
-  } finally {
-    unregister();
-  }
+  };
+  const value = rotation(scene, geo.cartesian3.fromDegrees(0, 0, 0), 90, null);
+  assert.equal(asked.length, 2, 'the anchor and the probe');
+  assert.ok(Math.abs(value - -Math.PI / 2) < 1e-9, `rotation ${value}`);
 });
@@ -1,5 +1,3 @@
-import { isGlobeEngine } from '../globe/contract.js';
-
 /**
 * Validation for positions that came back from a Cesium screen pick.
 *
@@ -54,28 +52,18 @@ export function isPickedWorldPosition(position) {
 * The world position under a screen point: the rendered surface where the
 * depth buffer has it, else the ellipsoid; null over the sky.
 *
- * @param {object} target The globe engine (`engine.picker.pickPosition`, then
- *   `engine.camera.pickEllipsoid`), or a Cesium viewer from callers that
- *   still hold one (`scene.pickPosition`, then `camera.pickEllipsoid`).
+ * @param {object} engine The globe engine (`engine.picker.pickPosition`,
+ *   then `engine.camera.pickEllipsoid`); without one, null.
 * @param {{x: number, y: number}} screenPosition
 * @returns {{x: number, y: number, z: number}|null} A Cartesian3.
 */
-export function pickGroundPosition(target, screenPosition) {
-  if (isGlobeEngine(target)) {
-    const { picker, camera } = target;
-    return groundUnder(
-      screenPosition,
-      picker.pickPositionSupported ? picker : null,
-      camera,
-    );
-  }
-  const scene = target?.scene;
+export function pickGroundPosition(engine, screenPosition) {
+  if (!engine) return null;
+  const { picker, camera } = engine;
  return groundUnder(
    screenPosition,
-    scene?.pickPositionSupported && typeof scene.pickPosition === 'function'
-      ? scene
-      : null,
-    typeof target?.camera?.pickEllipsoid === 'function' ? target.camera : null,
+    picker.pickPositionSupported ? picker : null,
+    camera,
  );
 }

@@ -162,20 +162,6 @@ test('the guard rejects each way Cesium mishandles a degenerate pick', () => {
  assert.ok(Math.abs(Cesium.Math.toDegrees(carto.latitude) - 30.2672) < 1e-6);
 });

-test('the ground under a click: the rendered surface, else the ellipsoid, never the sky', async () => {
-  const { pickGroundPosition } = await import('./scenePick.js');
-  const ground = { x: 6378137, y: 0, z: 0 };
-  const sky = { x: 500, y: 0, z: 0 };
-  const viewer = (picked, ellipsoid) => ({
-    scene: { pickPositionSupported: true, pickPosition: () => picked },
-    camera: { pickEllipsoid: () => ellipsoid },
-  });
-  assert.equal(pickGroundPosition(viewer(ground, null), {}), ground);
-  assert.equal(pickGroundPosition(viewer(sky, ground), {}), ground);
-  assert.equal(pickGroundPosition(viewer(undefined, undefined), {}), null);
-  assert.equal(pickGroundPosition(null, {}), null);
-});
-
 test('a surface pick is nothing, or Google 3D tile content without an id', async () => {
  const { isSurfacePick } = await import('./scenePick.js');
  assert.equal(isSurfacePick(undefined), true);
@@ -210,6 +196,9 @@ test('on a globe engine the ground is the picked surface, else the ellipsoid, ne
  unsupported.fake.script('pickEllipsoid', ground);
  assert.equal(pickGroundPosition(unsupported, screen), ground);
  assert.equal(unsupported.fake.callsOf('picker.pickPosition').length, 0);
+  unsupported.fake.script('pickEllipsoid', undefined);
+  assert.equal(pickGroundPosition(unsupported, screen), null);
+  assert.equal(pickGroundPosition(null, screen), null, 'no engine');
 });

 test('engine pick results classify like the Cesium picks they wrap', async () => {
@@ -10,6 +10,7 @@ import { createDirectionsSource } from '../layers/directions/source.js';
 import { createLifecycle as createCctvLifecycle } from '../layers/cctv/lifecycle.js';
 import { createCctvDisplay } from '../layers/cctv/render/display.js';
 import { createFakeEngine } from '../globe/testing/fakeEngine.js';
+import { createCesiumCredits } from '../globe/cesium/credits.js';
 import * as input from './inputOwnership.js';
 import { createOverpassAlprSource } from '../layers/alpr/source.js';

@@ -34,6 +35,11 @@ function viewer(t) {
  };
  return v;
 }
+// The Cesium engine's credits over the viewer double's credit display.
+const cesiumCredits = (v) => ({
+  credits: createCesiumCredits(v).credits,
+  render: { request: noop },
+});
 function assertCredit(v) {
  assert.ok(v.credits.some((credit) => credit.showOnScreen && credit.html.includes('>© OpenStreetMap<')));
 }
@@ -55,13 +61,13 @@ for (const index of [0, 1]) test(`${index ? 'dams' : 'datacenters'} introduce th
 test('Nepal locator introduces the shared OSM credit', async (t) => {
  const v = viewer(t);
  const layer = createBhoteKoshiLocatorLayer({ boundaryResolver: async () => ({ name: 'Nepal', ring: [[80, 26], [88, 26], [88, 30], [80, 30]] }), overlayHost, requestRender: noop, scheduleFrame: () => 1, cancelFrame: noop });
-  await layer.init(v); await layer.enable(v, { origin: 'scene' });
+  await layer.init(v, { engine: cesiumCredits(v) }); await layer.enable(v, { origin: 'scene' });
  assertCredit(v); await layer.destroy(v);
  assert.equal(v.credits.filter(c => c.showOnScreen).length, 0);
 });

 test('voice route geometry introduces the shared OSM credit', (t) => {
-  const v = viewer(t), renderer = createWorldAnnotationRenderer(v);
+  const v = viewer(t), renderer = createWorldAnnotationRenderer(v, { engine: cesiumCredits(v) });
  renderer.add({ id: 'route', type: 'route', color: 'primary', anchor: { lat: 0, lon: 0 }, path: [{ lat: 0, lon: 0 }, { lat: 0.01, lon: 0.01 }] });
  assertCredit(v); renderer.destroy();
  assert.equal(v.credits.filter(c => c.showOnScreen).length, 0);
@@ -173,8 +173,8 @@ function viewerAtHeight(height, { tilesLoaded = true, sampleHeight = () => undef
    trackedEntity: undefined,
    entities: { remove() {} },
  };
-  // The ground snap samples through the viewer's engine (engineFromViewer):
-  // the engine surface over this stub's tileset and scene.sampleHeight.
+  // The ground snap samples through the viewer's engine (the test
+  // renderer's surfaceOwner, engineFromViewer): the engine surface over this stub's tileset and scene.sampleHeight.
  registerViewerEngine(viewer, {
    isDestroyed: () => false,
    surface: {
@@ -34,8 +34,8 @@
 // rightWC, heading, pitch, roll, frustum.fovy) and `scene` scene-shaped
 // ({ camera, canvas.clientHeight, frameState.frameNumber }) for the shared
 // helpers that take them (iconOrientation, focusDeemphasis): adapters over
-// engine.camera.pose(), with the engine registered for the scene
-// (engineFromViewer) so projections go through its projector.
+// engine.camera.pose(), the scene carrying the engine's `projector` so
+// projections go through it.

 /**
 * @typedef {object} AircraftView
@@ -1364,8 +1364,7 @@ test('with SELECT BOX armed, Escape clears the preview first and the next Escape
  const fakes = boxToolFakes();
  const cancels = [];
  const tool = initImageryBoxTool({
-    viewer: fakes.viewer,
-    cesium: fakes.cesium,
+    engine: fakes.engine,
    pickWorld: fakes.pickWorld,
    documentRef: fakes.documentRef,
    onBox: (box) => f.layer.setBox(box),
@@ -1,6 +1,6 @@
 /**
 * Test doubles shared by the Recent Imagery tests: manual timers, fetch
- * responses, and the Cesium/viewer/document fakes the box tool needs.
+ * responses, and the engine and document fakes the box tool needs.
 */
 import { thumbnailOrder } from './model.js';

@@ -60,139 +60,116 @@ export function response({
  };
 }

-const EVENT_TYPES = {
-  LEFT_DOWN: 'down',
-  MOUSE_MOVE: 'move',
-  LEFT_UP: 'up',
-  LEFT_CLICK: 'click',
-  LEFT_DOUBLE_CLICK: 'dblclick',
-};
-
-/**
- * Cesium, viewer and document fakes for `initImageryBoxTool`. The canvas is
- * 1000 × 500 px mapped linearly onto 0.2° near Austin; y < 40 px is sky.
- */
-export function boxToolFakes() {
-  const handlers = [];
-  class ScreenSpaceEventHandler {
-    constructor(canvas) {
-      this.canvas = canvas;
-      this.actions = new Map();
-      this.destroyed = false;
-      handlers.push(this);
-    }
-    setInputAction(fn, type) {
-      this.actions.set(type, fn);
-    }
-    getInputAction(type) {
-      return this.actions.get(type);
-    }
-    removeInputAction(type) {
-      this.actions.delete(type);
-    }
-    destroy() {
-      this.destroyed = true;
-    }
-  }
-  class CustomDataSource {
-    constructor(name) {
-      this.name = name;
-      const values = [];
-      this.entities = {
-        values,
-        add: (entity) => (values.push(entity), entity),
-        removeAll: () => values.splice(0),
-      };
-    }
-  }
-  const color = { withAlpha: (alpha) => ({ alpha }) };
-  const cesium = {
-    ScreenSpaceEventHandler,
-    ScreenSpaceEventType: EVENT_TYPES,
-    CustomDataSource,
-    CallbackProperty: class {},
-    PolylineDashMaterialProperty: class {},
-    ClassificationType: { BOTH: 'both' },
-    Color: { fromCssColorString: () => color },
-    Rectangle: { fromDegrees: () => ({}) },
-    Cartesian3: { fromDegreesArray: (values) => values },
-  };
-
-  const stock = new ScreenSpaceEventHandler('stock');
-  const originalClick = () => 'select';
-  const originalDouble = () => 'track';
-  stock.setInputAction(originalClick, EVENT_TYPES.LEFT_CLICK);
-  stock.setInputAction(originalDouble, EVENT_TYPES.LEFT_DOUBLE_CLICK);
-  const sources = [];
-  const viewer = {
-    renders: 0,
-    scene: {
-      canvas: { clientWidth: 1000, clientHeight: 500 },
-      screenSpaceCameraController: { enableInputs: true },
-      requestRender: () => {
-        viewer.renders += 1;
-      },
-    },
-    screenSpaceEventHandler: stock,
-    dataSources: {
-      sources,
-      add: (source) => (sources.push(source), Promise.resolve(source)),
-      remove: (source) => sources.splice(sources.indexOf(source), 1),
-    },
-  };
-
+/** A DOM event target that keeps its listeners by type. */
+function eventTarget(extra = {}) {
  const listeners = [];
-  const classes = new Set();
-  const documentRef = {
+  return {
    listeners,
-    classes,
    addEventListener: (type, fn) => listeners.push([type, fn]),
    removeEventListener: (type, fn) => {
-      const index = listeners.findIndex((entry) => entry[1] === fn);
+      const index = listeners.findIndex(
+        (entry) => entry[0] === type && entry[1] === fn,
+      );
      if (index >= 0) listeners.splice(index, 1);
    },
+    dispatch(type, event) {
+      for (const [name, fn] of [...listeners]) if (name === type) fn(event);
+      return event;
+    },
+    ...extra,
+  };
+}
+
+/** A pointer or key event that records whether it was consumed. */
+function domEvent(fields) {
+  return {
+    prevented: false,
+    stopped: false,
+    preventDefault() {
+      this.prevented = true;
+    },
+    stopImmediatePropagation() {
+      this.stopped = true;
+    },
+    ...fields,
+  };
+}
+
+/**
+ * Globe engine and document fakes for `initImageryBoxTool`. The canvas is
+ * 1000 × 500 px mapped linearly onto 0.2° near Austin; y < 40 px is sky.
+ * `suspend: true` gives the engine input a counted suspendCameraInputs
+ * (Navara's); without it the tool turns setCameraInputs off and on.
+ */
+export function boxToolFakes({ suspend = false } = {}) {
+  const camera = { inputs: true, suspended: 0 };
+  const captured = new Set();
+  const canvas = eventTarget({
+    getBoundingClientRect: () => ({ left: 0, top: 0 }),
+    setPointerCapture: (id) => captured.add(id),
+    hasPointerCapture: (id) => captured.has(id),
+    releasePointerCapture: (id) => captured.delete(id),
+  });
+  const input = {
+    setCameraInputs(enabled) {
+      camera.inputs = Boolean(enabled);
+    },
+  };
+  if (suspend)
+    input.suspendCameraInputs = () => {
+      camera.suspended += 1;
+      return () => {
+        camera.suspended -= 1;
+      };
+    };
+  const engine = {
+    host: { canvas, size: () => ({ width: 1000, height: 500 }) },
+    input,
+  };
+  const windowRef = eventTarget();
+  const classes = new Set();
+  const documentRef = eventTarget({
+    classes,
+    defaultView: windowRef,
    body: {
      classList: {
        add: (name) => classes.add(name),
        remove: (name) => classes.delete(name),
      },
    },
-  };
-
-  const pickWorld = (_viewer, nx, ny) =>
+  });
+  const pickWorld = (_engine, nx, ny) =>
    ny * 500 < 40 ? null : { lon: -97.9 + nx * 0.2, lat: 30.4 - ny * 0.2 };
-  /** The live (non-stock) canvas handler, if the tool has one bound. */
-  const handler = () =>
-    handlers.find((h) => h.canvas !== 'stock' && !h.destroyed) || null;
-  const fire = (type, event) =>
-    handler()?.actions.get(EVENT_TYPES[type])?.(event);
+  const pointer = (at, fields = {}) =>
+    domEvent({
+      button: 0,
+      pointerId: 1,
+      clientX: at.x,
+      clientY: at.y,
+      ...fields,
+    });
+  /** Pointer events as the browser sends them: a press on the canvas, moves and the release on the document. */
+  const down = (at, fields) =>
+    canvas.dispatch('pointerdown', pointer(at, fields));
+  const move = (at, fields) =>
+    documentRef.dispatch('pointermove', pointer(at, fields));
+  const up = (at, fields) =>
+    documentRef.dispatch('pointerup', pointer(at, fields));
  /** Dispatch a keydown to the tool's document listener. */
-  const key = (name) => {
-    const event = {
-      key: name,
-      prevented: false,
-      stopped: false,
-      preventDefault() {
-        this.prevented = true;
-      },
-      stopImmediatePropagation() {
-        this.stopped = true;
-      },
-    };
-    listeners.find(([type]) => type === 'keydown')?.[1](event);
-    return event;
-  };
+  const key = (name) =>
+    documentRef.dispatch('keydown', domEvent({ key: name }));
  return {
-    cesium,
-    viewer,
+    engine,
+    canvas,
+    camera,
+    captured,
    documentRef,
+    windowRef,
    pickWorld,
-    handler,
-    fire,
+    down,
+    move,
+    up,
    key,
-    types: EVENT_TYPES,
-    originalClick,
-    originalDouble,
  };
 }

@@ -1,13 +1,12 @@
 // An engine-contract view shared by layer renderers and the celestial HUD:
 // `camera` camera-shaped and `scene`
 // scene-shaped adapters over engine.camera.pose() (refreshed once per frame,
-// and whenever the camera moved), with the engine registered for the scene
-// (engineFromViewer) so the shared helpers (iconOrientation, focus) project
-// through its projector; the frame number, frustum and horizon tests, the
-// window projection and the frame/camera events. No three, no Cesium.
+// and whenever the camera moved), the scene carrying the engine's projector
+// so the shared helpers (iconOrientation, focus) project through it; the
+// frame number, frustum and horizon tests, the window projection and the
+// frame/camera events. No three, no Cesium.

 import * as geo from '../../../geo/index.js';
-import { registerViewerEngine } from '../../../globe/cesium/engineFromViewer.js';

 /**
 * @param {import('../../../globe/contract.js').GlobeEngine} engine
@@ -87,9 +86,9 @@ export function createEngineLayerView(
        return frameNumber;
      },
    },
+    // What the shared helpers project through.
+    projector: engine.projector,
  };
-  // Shared helpers project through the engine registered for their scene.
-  removers.push(registerViewerEngine(scene, engine));
  const horizon = {
    isPointVisible: (position) => engine.projector.horizonVisible(position),
  };
@@ -19,8 +19,8 @@
 // The view: `camera` camera-shaped (positionWC, positionCartographic,
 // rightWC, upWC, heading, pitch, roll, pickEllipsoid(screen)) and `scene`
 // scene-shaped ({ camera, canvas }) for the shared helpers that take them
-// (iconOrientation, the view-area request), with the engine registered for
-// the scene (engineFromViewer) so projections go through its projector.
+// (iconOrientation, the view-area request), the scene carrying the engine's
+// `projector` so projections go through it.

 /**
 * @typedef {object} VesselView
@@ -10,11 +10,11 @@ export class MapStackController extends MapSourceController {
    const googleApiKey =
      typeof window !== 'undefined' ? window.__GOOGLE_MAPS_API_KEY__ : '';
    // Sources for the page's engine: Navara builds its own from the
-    // descriptions (src/maps/defaultSources.js).
+    // descriptions (src/maps/defaultSources.js). Without an engine, Cesium's.
    const registry = createDefaultMapSources({
      ...options,
      googleApiKey,
-      engineKind: options.engine?.kind === 'navara' ? 'navara' : 'cesium',
+      engineKind: options.engine?.kind ?? 'cesium',
    });
    super(viewer, {
      registry,
@@ -1,5 +1,4 @@
 import * as geo from '../geo/index.js';
-import { isGlobeEngine } from '../globe/contract.js';
 import { WORLD_OVERLAY_OCCLUDER_SELECTORS } from './worldOverlayChrome.js';
 export { WORLD_OVERLAY_OCCLUDER_SELECTORS } from './worldOverlayChrome.js';
 import {
@@ -2727,7 +2726,8 @@ function createDevFacade() {
 * @param {import('../globe/contract.js').GlobeEngine} engine
 */
 export function initWorldOverlay(engine) {
-  if (!isGlobeEngine(engine))
+  // What the host reads of the engine: a Cesium viewer has none of it.
+  if (!engine?.projector || !engine.frames?.postRender || !engine.host)
    throw new TypeError('initWorldOverlay requires a globe engine');
  if (_engine === engine && _canvas && _removePostRender) return;
  if (_engine) destroyWorldOverlay();
@@ -410,7 +410,7 @@ test('annotation capability miss keeps its pin and exposes the unavailable label
    event,
    attempts = 0;
  const engine = createAnnotationEngine({
-    viewer: {},
+    globe: {},
    renderer: {
      add() {},
      update(mark) {
@@ -38,12 +38,10 @@
 * `scene.requestRender()`. It needs no frame events (`engine.frames`).
 *
 * Any other globe engine (Navara) is the governor's backend instead: install
- * it on the engine and the owner-counted holds drive
- * `engine.render.setContinuous`, requests go to `engine.render.request`.
+ * it on the engine (installEngineRenderGovernor) and the owner-counted holds
+ * drive `engine.render.setContinuous`, requests go to `engine.render.request`.
 */

-import { isGlobeEngine } from './globe/contract.js';
-
 let _viewer = null;
 /** The non-Cesium engine the governor drives, or null (Cesium: `_viewer`). */
 let _engine = null;
@@ -75,22 +73,14 @@ function applyMode() {
 }

 /**
- * Install the governor on the viewer. Idempotent. Before install,
- * hold/release still record into the holds set (and apply at install time);
- * requests are safe no-ops — so modules can call all three unconditionally
- * in tests without a viewer.
- * @param {Cesium.Viewer | import('./globe/contract.js').GlobeEngine} viewer
- *   The Cesium viewer, or a non-Cesium globe engine.
+ * Install the governor on a Cesium viewer, as the Cesium engine's render
+ * backend. Idempotent. Before install, hold/release still record into the
+ * holds set (and apply at install time); requests are safe no-ops — so
+ * modules can call all three unconditionally in tests without a viewer.
+ * @param {Cesium.Viewer} viewer
 * @returns {void}
 */
 export function installRenderGovernor(viewer) {
-  if (isGlobeEngine(viewer) && viewer.kind !== 'cesium') {
-    _engine = viewer;
-    _viewer = viewer;
-    _installed = true;
-    applyMode();
-    return;
-  }
  if (!viewer?.scene)
    throw new TypeError('installRenderGovernor requires a Cesium viewer');
  _engine = null;
@@ -103,6 +93,22 @@ export function installRenderGovernor(viewer) {
  applyMode();
 }

+/**
+ * Install the governor on a globe engine that renders by itself (Navara):
+ * the holds drive `engine.render.setContinuous`, requests go to
+ * `engine.render.request`. Idempotent, like installRenderGovernor.
+ * @param {import('./globe/contract.js').GlobeEngine} engine
+ * @returns {void}
+ */
+export function installEngineRenderGovernor(engine) {
+  if (typeof engine?.render?.setContinuous !== 'function')
+    throw new TypeError('installEngineRenderGovernor requires a globe engine');
+  _engine = engine;
+  _viewer = engine;
+  _installed = true;
+  applyMode();
+}
+
 /**
 * Register a continuous-render hold. Idempotent per owner.
 * Call where the owner's per-frame work BEGINS (scene listener installed,
@@ -2,6 +2,7 @@ import { test, beforeEach } from 'node:test';
 import assert from 'node:assert/strict';
 import {
  installRenderGovernor,
+  installEngineRenderGovernor,
  holdContinuousRender,
  releaseContinuousRender,
  governorRequestRender,
@@ -118,7 +119,7 @@ test('on a non-Cesium globe engine the governor drives engine.render with owner-
  _resetRenderGovernorForTest();
  const engine = createFakeEngine({ kind: 'navara' });
  holdContinuousRender('before-install');
-  installRenderGovernor(engine);
+  installEngineRenderGovernor(engine);
  assert.equal(engine.render.isContinuous(), true, 'a hold taken before install applies');
  releaseContinuousRender('before-install');
  assert.equal(engine.render.isContinuous(), false);
@@ -141,7 +142,7 @@ test('releasing an absent Navara hold does not wake an already idle engine', asy
  const { createFakeEngine } = await import('./globe/testing/fakeEngine.js');
  _resetRenderGovernorForTest();
  const engine = createFakeEngine({ kind: 'navara' });
-  installRenderGovernor(engine);
+  installEngineRenderGovernor(engine);
  engine.fake.resetCalls();
  for (let i = 0; i < 22; i++) releaseContinuousRender('cctv-projection');
  assert.equal(engine.fake.callsOf('render.request').length, 0);
@@ -116,7 +116,7 @@ export class SceneDirector {
    });
    this._sharing = createSceneSharing(this);
    this._interactionTransitions = 0;
-    this._interactions = createSceneInteractions(viewer, {
+    this._interactions = createSceneInteractions({
      engine,
      available: () =>
        !this._destroyed && !this._running && !this.viewer?.trackedEntity,
@@ -255,7 +255,7 @@ export class SceneDirector {
    });
    this._cameraHandoffUnsubscribe?.();
    this._removeCameraInput?.();
-    this._interactions.setScene(null, null);
+    this._interactions.setScene(null);
    this._dataPacks.setScene(null, null);
    this._flight?.suspend();
    this.engine = this.viewer = null;
@@ -268,7 +268,7 @@ export class SceneDirector {
    this._isMapStackAvailable = isAvailable;
    try {
      this._dataPacks.setScene(viewer, native, engine.host.container);
-      this._interactions.setScene(viewer, engine, this._dataPacks.getTargets());
+      this._interactions.setScene(engine, this._dataPacks.getTargets());
    } catch (error) {
      // Release any packs already drawn before the caller parks the failed globe.
      this.suspendScene();
@@ -1,4 +1,3 @@
-import * as Cesium from 'cesium';
 import { nextTick } from 'vue';
 import { isPointerFree } from '../data/inputOwnership.js';
 import { createInteractionSession } from '../director/interactions/session.js';
@@ -9,21 +8,19 @@ import { applicationPinia } from '../ui/vueRuntime.js';
 /**
 * Own the active shot's pick handler, accessible actions and plain-text
 * feedback. The Scene actions panel is presented to the scene interactions
- * store, which its view renders inside the viewer's container.
+ * store, which its view renders inside the globe engine's container. A
+ * feature is picked through engine.input (a click with its pick).
 */
 // Keys each activation's panel, so a new one never reuses an old one's DOM.
 let activations = 0;

-export function createSceneInteractions(
-  viewer,
-  {
-    execute,
-    engine = null,
-    available = () => true,
-    store = useSceneInteractionsStore(applicationPinia()),
-  },
-) {
-  let container = engine?.host?.container ?? viewer?.container;
+export function createSceneInteractions({
+  execute,
+  engine = null,
+  available = () => true,
+  store = useSceneInteractionsStore(applicationPinia()),
+}) {
+  let container = engine?.host?.container;
  let panel = null,
    handler,
    items = [],
@@ -79,7 +76,7 @@ export function createSceneInteractions(
    return ok;
  }
  function bindInput(owner) {
-    if (!engine && !viewer) return;
+    if (!engine) return;
    const click = (event) => {
      if (
        panel?.owner !== owner ||
@@ -88,9 +85,7 @@ export function createSceneInteractions(
        !available()
      )
        return;
-      const picked = engine
-        ? event.picked?.id
-        : viewer.scene.pick(event.position)?.id;
+      const picked = event.picked?.id;
      const matches = items.filter(
        (item) =>
          targets.get(
@@ -108,32 +103,26 @@ export function createSceneInteractions(
      void nextTick(() => {
        if (panel?.owner !== owner || !shown()) return;
        const id = globalThis.CSS?.escape?.(matches[0].id) ?? matches[0].id;
-        (engine?.host.container ?? viewer?.container)
+        engine?.host.container
          ?.querySelector?.(
            `[data-director-interactions] [data-director-action="${id}"]`,
          )
          ?.focus({ preventScroll: true });
      });
    };
-    if (engine) {
-      handler = { destroy: engine.input.on('click', click, { pick: true }) };
-    } else {
-      handler = new Cesium.ScreenSpaceEventHandler(viewer.scene.canvas);
-      handler.setInputAction(click, Cesium.ScreenSpaceEventType.LEFT_CLICK);
-    }
+    handler = { destroy: engine.input.on('click', click, { pick: true }) };
  }
  return {
    clear,
    destroy: clear,
    getState: session.getState,
-    setScene(nextViewer, nextEngine, registered) {
+    setScene(nextEngine, registered) {
      handler?.destroy();
      handler = null;
-      viewer = nextViewer;
      engine = nextEngine;
      if (registered) targets = registered;
-      if (!panel || (!engine && !viewer)) return;
-      container = engine?.host?.container ?? viewer?.container ?? container;
+      if (!panel || !engine) return;
+      container = engine.host?.container ?? container;
      update({ container });
      bindInput(panel.owner);
    },
@@ -1,5 +1,5 @@
 // src/scenes/interactionsView.test.mjs — the Scene actions panel renders in
-// the viewer's container from what the scene interactions owner presents.
+// the engine's container from what the scene interactions owner presents.
 import '../testSupport/registerDom.mjs';
 import test from 'node:test';
 import assert from 'node:assert/strict';
@@ -8,6 +8,7 @@ import { createPinia } from 'pinia';
 import { useSceneInteractionsStore } from '../ui/stores/sceneInteractions.js';
 import SceneInteractions from '../ui/views/panels/SceneInteractions.vue';
 import { createSceneInteractions } from './interactions.js';
+import { createFakeEngine } from '../globe/testing/fakeEngine.js';

 const target = (featureId) => ({ packId: 'qa', featureId });
 const key = (featureId) => JSON.stringify(['qa', featureId]);
@@ -36,25 +37,25 @@ function fixture(t, { execute = async () => true } = {}) {
  const app = createApp(SceneInteractions).use(pinia);
  app.mount(document.body.appendChild(document.createElement('div')));
  const executed = [];
-  const interactions = createSceneInteractions(
-    { container, scene: { canvas, pick: () => null } },
-    {
-      execute: (action, signal) => {
-        executed.push(action.type);
-        return execute(action, signal);
-      },
-      store: useSceneInteractionsStore(pinia),
+  const engine = createFakeEngine({ container, canvas });
+  const interactions = createSceneInteractions({
+    engine,
+    execute: (action, signal) => {
+      executed.push(action.type);
+      return execute(action, signal);
    },
-  );
+    store: useSceneInteractionsStore(pinia),
+  });
  t.after(() => {
    interactions.destroy();
    app.unmount();
+    engine.destroy();
  });
  const $ = (selector) => container.querySelector(selector);
  const settle = async () => {
    for (let flush = 0; flush < 4; flush += 1) await nextTick();
  };
-  return { interactions, container, executed, $, settle, pinia };
+  return { interactions, engine, container, executed, $, settle, pinia };
 }

 test('a shot with actions shows its panel in the viewer container', async (t) => {
@@ -175,11 +176,12 @@ test('a button reused before the next render still belongs to its own panel', as
 });

 test("an earlier owner leaves a later owner's panel alone", async (t) => {
-  const { interactions, container, $, settle, pinia } = fixture(t);
-  const later = createSceneInteractions(
-    { container, scene: { canvas: $('canvas'), pick: () => null } },
-    { execute: async () => true, store: useSceneInteractionsStore(pinia) },
-  );
+  const { interactions, engine, $, settle, pinia } = fixture(t);
+  const later = createSceneInteractions({
+    engine,
+    execute: async () => true,
+    store: useSceneInteractionsStore(pinia),
+  });
  t.after(() => later.destroy());
  interactions.activate(SHOT, new Map([[key('point'), {}]]));
  later.activate(SHOT, new Map([[key('point'), {}]]));
@@ -190,3 +192,28 @@ test("an earlier owner leaves a later owner's panel alone", async (t) => {
  await settle();
  assert.equal(later.getState().selected, 'fly');
 });
+
+test('a click on a feature of the shot outlines its actions through engine.input', async (t) => {
+  const { interactions, engine, $, settle } = fixture(t);
+  const feature = { kind: 'pack-feature' };
+  interactions.activate(SHOT, new Map([[key('point'), feature]]));
+  await settle();
+  engine.fake.script('pick', { id: { kind: 'other' } });
+  engine.fake.input('click', { position: { x: 10, y: 10 } });
+  await settle();
+  assert.deepEqual(interactions.getState().outlined ?? [], []);
+  assert.equal(
+    $('[data-director-action="card"]').style.outline,
+    '',
+    'another object selects nothing',
+  );
+  engine.fake.script('pick', { id: feature });
+  engine.fake.input('click', { position: { x: 10, y: 10 } });
+  await settle();
+  assert.equal(
+    $('[role=status]').textContent,
+    'Selected feature: point. Choose an action.',
+  );
+  assert.ok($('[data-director-action="card"]').style.outline);
+  assert.ok($('[data-director-action="fly"]').style.outline);
+});
@@ -47,7 +47,6 @@
 */

 import * as geo from '../geo/index.js';
-import { engineFromViewer } from '../globe/cesium/engineFromViewer.js';
 import { acceptedSurfaceHeight } from '../globe/surfaceDetail.js';
 import { MAX_FLOOR_TILE_SIZE_M } from './meshFloorSampler.js';

@@ -155,7 +154,7 @@ export function firstVisibleTileset(primitives) {
 /**
 * Create a per-layer ground-snap cache.
 * @returns {{
- *   heightFor: (target: object, icao: string, pos: Cesium.Cartesian3,
+ *   heightFor: (engine: object, icao: string, pos: Cesium.Cartesian3,
 *               getExclusions?: () => Array<unknown>) => number|null,
 *   forget: (icao: string) => void,
 *   clear: () => void,
@@ -266,9 +265,8 @@ export function createGroundSnap({ groundFloor }) {
   * A contact that HAS resolved once keeps that answer through a resample outage;
   * see `heldSnapM`.
   *
-   * @param {object} target - The globe engine (`engine.surface`:
-   *   sampleHeightDetailed and tilesLoaded), or a viewer whose engine is
-   *   registered (engineFromViewer); without one, no sample.
+   * @param {object} engine - The globe engine (`engine.surface`:
+   *   sampleHeightDetailed and tilesLoaded); without one, no sample.
   * @param {string} icao - Cache key (per-layer icao space).
   * @param {Cesium.Cartesian3} pos - Current display position. Cache movement
   *   is measured after projecting this input to the WGS84 ellipsoid, so a
@@ -279,8 +277,7 @@ export function createGroundSnap({ groundFloor }) {
   *   lands on its icon/model otherwise). Only invoked when a sample fires.
   * @returns {number|null}
   */
-  function heightFor(target, icao, pos, getExclusions) {
-    const engine = engineFromViewer(target);
+  function heightFor(engine, icao, pos, getExclusions) {
    const surfacePos = geo.ellipsoid.WGS84.scaleToGeodeticSurface(
      pos,
      scratchSurfacePos,
@@ -52,9 +52,7 @@ test('on a globe engine loading tiles or a miss return null without a sample cac
  assert.equal(engine.fake.callsOf('surface.sampleHeightDetailed').length, 1);
 });

-test('a coarse tile answer or only terrain is a miss; a viewer reaches its engine', async () => {
-  const { registerViewerEngine } =
-    await import('../globe/cesium/engineFromViewer.js');
+test('a coarse tile answer or only terrain is a miss', async () => {
  const snap = createGroundSnap({ groundFloor: groundFloor() });
  const engine = createFakeEngine();
  engine.fake.script('sampleHeightDetailed', () => ({
@@ -73,14 +71,8 @@ test('a coarse tile answer or only terrain is a miss; a viewer reaches its engin
    source: 'tiles',
    tileSizeM: 241,
  }));
-  const viewer = {};
-  const unregister = registerViewerEngine(viewer, engine);
-  try {
-    assert.equal(snap.heightFor(viewer, 'd3', KAUS), 122.5);
-  } finally {
-    unregister();
-  }
-  assert.equal(snap.heightFor({}, 'd4', KAUS), null, 'no engine: no sample');
+  assert.equal(snap.heightFor(engine, 'd3', KAUS), 122.5);
+  assert.equal(snap.heightFor(null, 'd4', KAUS), null, 'no engine: no sample');
 });

 const atDenverAirport = geo.cartesian3.fromDegrees(-104.6737, 39.8561, 0);
@@ -1,5 +1,4 @@
 import * as geo from '../geo/index.js';
-import { engineFromViewer } from '../globe/cesium/engineFromViewer.js';
 import { acceptedSurfaceHeight } from '../globe/surfaceDetail.js';

 /** Answers from tiles larger than this are too coarse to latch (m).
@@ -86,9 +85,8 @@ export function createMeshFloorSampler({
   * layer poll (never per contact, never per frame). Synchronous — Cesium's
   * sampleHeight is a CPU-side query against loaded tiles.
   *
-   * @param {object|undefined} target - The globe engine (engine.surface,
-   *   camera.height, maps.photorealActive), or a viewer or scene whose
-   *   engine is registered (engineFromViewer); without one, nothing.
+   * @param {object|undefined} engine - The globe engine (engine.surface,
+   *   camera.height, maps.photorealActive); without one, nothing.
   * @param {Array<{lat: number, lon: number}>} points - Contact/waypoint coords.
   * @param {object} [options]
   * @param {Array<object>} [options.excludeObjects] - What the probe passes
@@ -98,12 +96,11 @@ export function createMeshFloorSampler({
   *   Viewer subpoint (computed once by the caller's poll).
   */
  function sampleMeshFloorCells(
-    target,
+    engine,
    points,
    { excludeObjects = [], viewerLat, viewerLon } = {},
  ) {
    if (!meshFloorPreferred()) return;
-    const engine = engineFromViewer(target);
    if (!engine || engine.isDestroyed?.() || !engine.surface.supported) return;
    if (!Array.isArray(points) || !points.length) return;
    // Round-5 hardening (the CCTV projectionTilesReady lesson, ported late):
@@ -74,11 +74,13 @@ export function aircraftViewerRenderer({
    get scene() {
      return viewer?.scene;
    },
+    // The engine registered for the viewer (the surface samplers take an
+    // engine).
    get surfaceOwner() {
-      return viewer;
+      return engine ?? engineFromViewer(viewer);
    },
    get surfaceScene() {
-      return viewer?.scene;
+      return engine ?? engineFromViewer(viewer);
    },
    frameNumber: () => viewer?.scene?.frameState?.frameNumber ?? -1,
    viewportHeightPx: () => viewer.scene.canvas.clientHeight,
@@ -36,3 +36,19 @@ export function trackingEngine(viewer) {
  });
  return engine;
 }
+
+/**
+ * A globe engine with only the camera of a viewer test double: its pose at
+ * the double's positionCartographic and its view rectangle. It has no canvas
+ * (screen picks miss) and no surface (ground heights are 0).
+ */
+export function cameraOnlyEngine(viewer) {
+  const camera = viewer?.camera;
+  return {
+    camera: {
+      pose: () => ({ cartographic: camera?.positionCartographic }),
+      viewRectangle: () => camera?.computeViewRectangle?.(),
+    },
+    host: { size: () => ({ width: 0, height: 0 }) },
+  };
+}
@@ -1,159 +0,0 @@
-import * as geo from '../geo/index.js';
-import {
-  claimPointer,
-  pointerOwner,
-  releasePointer,
-} from '../data/inputOwnership.js';
-import { validateBox } from '../layers/recentImagery/model.js';
-
-/** Native DOM capture keeps a box drag out of Navara's camera controller. */
-export function initNavaraImageryBoxTool({
-  engine,
-  onBox,
-  onPreview,
-  onCancel,
-  onActive,
-  onEscape,
-  documentRef = globalThis.document,
-}) {
-  const canvas = engine.host.canvas;
-  let active = false,
-    destroyed = false,
-    anchor = null,
-    corner = null;
-  let lease = null,
-    thaw = null,
-    pointerId = null;
-  const box = () =>
-    anchor && {
-      west: Math.min(anchor.lon, corner.lon),
-      east: Math.max(anchor.lon, corner.lon),
-      south: Math.min(anchor.lat, corner.lat),
-      north: Math.max(anchor.lat, corner.lat),
-    };
-  function point(event) {
-    const rect = canvas.getBoundingClientRect(),
-      at = { x: event.clientX - rect.left, y: event.clientY - rect.top };
-    const hit = engine.picker.pickPosition(at) || engine.picker.pickGlobe(at);
-    const c = hit && geo.cartographic.fromCartesian(hit, geo.ellipsoid.WGS84);
-    return c
-      ? {
-          lon: (c.longitude * 180) / Math.PI,
-          lat: (c.latitude * 180) / Math.PI,
-        }
-      : null;
-  }
-  const consume = (event) => {
-    event.preventDefault?.();
-    event.stopImmediatePropagation?.();
-  };
-  function endDrag() {
-    anchor = corner = null;
-    if (pointerId !== null && canvas.hasPointerCapture?.(pointerId))
-      canvas.releasePointerCapture(pointerId);
-    pointerId = null;
-    thaw?.();
-    thaw = null;
-    onPreview(null);
-  }
-  function down(event) {
-    if (
-      !active ||
-      anchor ||
-      event.button !== 0 ||
-      event.shiftKey ||
-      event.ctrlKey ||
-      event.altKey
-    )
-      return;
-    consume(event);
-    const p = point(event);
-    if (!p) {
-      onCancel?.('sky', 'Press on the ground, not the sky');
-      return;
-    }
-    anchor = corner = p;
-    pointerId = event.pointerId;
-    thaw = engine.input.suspendCameraInputs();
-    canvas.setPointerCapture?.(pointerId);
-    onPreview(box());
-  }
-  function move(event) {
-    if (!anchor || event.pointerId !== pointerId) return;
-    consume(event);
-    corner = point(event) || corner;
-    onPreview(box());
-  }
-  function up(event) {
-    if (!anchor || event.pointerId !== pointerId) return;
-    consume(event);
-    corner = point(event) || corner;
-    const selected = box(),
-      result = validateBox(selected);
-    if (result.reason === 'degenerate') result.message = 'Drag to size the box';
-    stop();
-    if (result.ok) onBox(result.box);
-    else onCancel?.(result.reason, result.message, selected);
-  }
-  function key(event) {
-    if (!active || event.key !== 'Escape') return;
-    consume(event);
-    if (onEscape?.() !== true) cancel('escape');
-  }
-  function pointerCancel(event) {
-    if (anchor && event.pointerId === pointerId) cancel('pointer-cancel');
-  }
-  const bindings = [
-    [canvas, 'pointerdown', down],
-    [documentRef, 'pointermove', move],
-    [documentRef, 'pointerup', up],
-    [documentRef, 'pointercancel', pointerCancel],
-    [documentRef, 'keydown', key],
-  ];
-  if (documentRef.defaultView)
-    bindings.push([documentRef.defaultView, 'blur', () => cancel('blur')]);
-  function stop() {
-    if (!active) return;
-    for (const [target, type, listener] of bindings)
-      target.removeEventListener(type, listener, true);
-    endDrag();
-    releasePointer(lease);
-    lease = null;
-    active = false;
-    documentRef.body?.classList.remove('gev-imagery-box');
-    onActive?.(false);
-  }
-  function cancel(reason = 'cancel') {
-    if (active) {
-      stop();
-      onCancel?.(reason);
-    }
-  }
-  return {
-    start() {
-      if (destroyed) return false;
-      if (active) return true;
-      lease = claimPointer('recent-imagery-box');
-      if (!lease) {
-        onCancel?.(
-          'pointer-busy',
-          `${pointerOwner()} is using the pointer — close it first`,
-        );
-        return false;
-      }
-      active = true;
-      for (const [target, type, listener] of bindings)
-        target.addEventListener(type, listener, true);
-      documentRef.body?.classList.add('gev-imagery-box');
-      onActive?.(true);
-      return true;
-    },
-    cancel,
-    isActive: () => active,
-    destroy() {
-      if (destroyed) return;
-      stop();
-      destroyed = true;
-    },
-  };
-}
@@ -1,82 +0,0 @@
-import test from 'node:test';
-import assert from 'node:assert/strict';
-import * as geo from '../geo/index.js';
-import { pointerOwner } from '../data/inputOwnership.js';
-import { initNavaraImageryBoxTool } from './imageryBoxNavara.js';
-
-test('blur and destruction during a Navara box drag return input and pointer ownership', () => {
-  const target = () => {
-    const listeners = new Map();
-    return {
-      listeners,
-      addEventListener(type, fn) {
-        listeners.set(type, fn);
-      },
-      removeEventListener(type) {
-        listeners.delete(type);
-      },
-    };
-  };
-  const windowRef = target(),
-    documentRef = {
-      ...target(),
-      defaultView: windowRef,
-      body: { classList: { add() {}, remove() {} } },
-    };
-  const canvas = {
-    ...target(),
-    getBoundingClientRect: () => ({ left: 0, top: 0 }),
-    setPointerCapture() {},
-    hasPointerCapture: () => true,
-    releasePointerCapture() {},
-  };
-  let suspended = 0,
-    preview = null;
-  const engine = {
-    host: { canvas },
-    picker: { pickPosition: () => geo.cartesian3.fromDegrees(10, 20, 0) },
-    input: {
-      suspendCameraInputs() {
-        suspended++;
-        return () => suspended--;
-      },
-    },
-  };
-  const tool = initNavaraImageryBoxTool({
-    engine,
-    documentRef,
-    onBox() {},
-    onPreview: (b) => (preview = b),
-  });
-  const down = () =>
-    canvas.listeners.get('pointerdown')({
-      button: 0,
-      pointerId: 1,
-      clientX: 10,
-      clientY: 20,
-      preventDefault() {},
-      stopImmediatePropagation() {},
-    });
-  try {
-    assert.equal(tool.start(), true);
-    down();
-    assert.equal(suspended, 1);
-    assert.ok(preview);
-    windowRef.listeners.get('blur')();
-    assert.equal(suspended, 0);
-    assert.equal(preview, null);
-    assert.equal(pointerOwner(), null);
-    assert.equal(tool.isActive(), false);
-    tool.start();
-    down();
-    tool.destroy();
-    tool.destroy();
-    assert.equal(suspended, 0);
-    assert.equal(pointerOwner(), null);
-    assert.equal(canvas.listeners.size, 0);
-    assert.equal(documentRef.listeners.size, 0);
-    assert.equal(windowRef.listeners.size, 0);
-  } finally {
-    tool.destroy();
-  }
-});
@@ -1,11 +1,16 @@
 /**
 * Box selection for the Recent Imagery layer: press on the world, drag, and
 * release to hand the layer a degrees box. Follows the draw tool's ownership
- * rules — the pointer is claimed for the session, the viewer's own click
- * actions are borrowed and given back, and `destroy()` returns everything —
- * and freezes the camera only while a drag is in progress.
+ * rules — the pointer is claimed for the session and `destroy()` returns
+ * everything — and freezes the camera only while a drag is in progress.
+ *
+ * The same on every engine: the tool takes the pointer events of the
+ * engine's canvas in the capture phase, ahead of the engine's own handlers,
+ * so a press that starts a box and the drag it makes reach neither the
+ * camera nor any click (a layer's, or Cesium's stock select and track).
+ * Moves outside a drag pass through. The layer draws the preview
+ * (`onPreview`, a ground cell on engine.ground).
 */
-import * as Cesium from 'cesium';
 import { pickWorldFromScreen } from '../annotations/annotationResolver.js';
 import {
  claimPointer,
@@ -18,35 +23,51 @@ import { msg } from '../i18n/index.js';
 /** The id this tool claims the pointer under. */
 export const IMAGERY_BOX_POINTER_OWNER = 'recent-imagery-box';

+/**
+ * The camera held still until the returned release: the engine's counted
+ * suspension where it has one (Navara keeps the app's own setCameraInputs
+ * choice under it), else camera inputs off and on again.
+ */
+function freezeCamera(input) {
+  if (typeof input.suspendCameraInputs === 'function')
+    return input.suspendCameraInputs();
+  input.setCameraInputs(false);
+  return () => input.setCameraInputs(true);
+}
+
 /**
 * Wire the box tool.
- * @param {{ viewer: object, onBox: (box: object) => void, onCancel?: (reason: string, message?: string, box?: object) => void, onActive?: (active: boolean) => void, onEscape?: () => boolean, cesium?: object, pickWorld?: Function, documentRef?: object }} deps
- *   `onEscape` runs before the tool cancels on Escape; returning `true` claims
- *   the key (it is still consumed) and leaves the tool armed.
- * @returns {{ start: () => boolean, cancel: (reason?: string) => void, isActive: () => boolean, destroy: () => Promise<void> } | null}
+ * @param {{ engine: import('../globe/contract.js').GlobeEngine,
+ *   onBox: (box: object) => void, onPreview?: (box: object | null) => void,
+ *   onCancel?: (reason: string, message?: string, box?: object) => void,
+ *   onActive?: (active: boolean) => void, onEscape?: () => boolean,
+ *   pickWorld?: Function, documentRef?: object }} deps
+ *   `onPreview` gets the box being dragged, and null once the drag ends.
+ *   `onEscape` runs before the tool cancels on Escape; returning `true`
+ *   claims the key (it is still consumed) and leaves the tool armed.
+ * @returns {{ start: () => boolean, cancel: (reason?: string) => void, isActive: () => boolean, destroy: () => void } | null}
 */
 export function initImageryBoxTool({
-  viewer,
+  engine,
  onBox,
+  onPreview = () => {},
  onCancel,
  onActive,
  onEscape,
-  cesium = Cesium,
  pickWorld = pickWorldFromScreen,
  documentRef = globalThis.document,
 } = {}) {
-  if (!viewer?.scene || typeof onBox !== 'function') return null;
+  const canvas = engine?.host?.canvas;
+  if (!canvas || typeof onBox !== 'function') return null;

  let active = false;
  let destroyed = false;
  /** Drag corners in degrees; `anchor` is null while no drag is live. */
  let anchor = null;
  let corner = null;
-  let handler = null;
  let lease = null;
-  let savedSingleClick = null;
-  let savedDoubleClick = null;
-  let savedCameraInputs = null;
+  let thaw = null;
+  let pointerId = null;

  const dragBox = () =>
    anchor && {
@@ -55,241 +76,144 @@ export function initImageryBoxTool({
      east: Math.max(anchor.lon, corner.lon),
      north: Math.max(anchor.lat, corner.lat),
    };
-
-  const dataSource = new cesium.CustomDataSource(
-    'gev-recent-imagery-box-preview',
-  );
-  let attaching = Promise.resolve(viewer.dataSources.add(dataSource)).catch(
-    () => null,
-  );
-  const stroke = cesium.Color.fromCssColorString('#8be9ff');
-  const previewRectangle = () => {
-    const box = dragBox();
-    return box
-      ? cesium.Rectangle.fromDegrees(box.west, box.south, box.east, box.north)
-      : undefined;
-  };
-  const previewOutline = () => {
-    const box = dragBox();
-    if (!box) return [];
-    return cesium.Cartesian3.fromDegreesArray([
-      box.west,
-      box.south,
-      box.east,
-      box.south,
-      box.east,
-      box.north,
-      box.west,
-      box.north,
-      box.west,
-      box.south,
-    ]);
-  };
-  const fill = dataSource.entities.add({
-    show: false,
-    rectangle: {
-      coordinates: new cesium.CallbackProperty(previewRectangle, false),
-      material: stroke.withAlpha(0.12),
-      classificationType: cesium.ClassificationType.BOTH,
-    },
-  });
-  // A rectangle graphic cannot draw a dashed edge on the ground, so the
-  // outline is its own draped polyline traced round the same corners.
-  const outline = dataSource.entities.add({
-    show: false,
-    polyline: {
-      positions: new cesium.CallbackProperty(previewOutline, false),
-      width: 2,
-      clampToGround: true,
-      classificationType: cesium.ClassificationType.BOTH,
-      material: new cesium.PolylineDashMaterialProperty({
-        color: stroke.withAlpha(0.95),
-        dashLength: 12,
-      }),
-    },
-  });
-
-  const requestRender = () => viewer.scene.requestRender?.();
-  const setPreview = (visible) => {
-    fill.show = visible;
-    outline.show = visible;
-    requestRender();
-  };
-  const worldAt = (position) => {
-    if (!position) return null;
-    const canvas = viewer.scene.canvas;
-    const w = canvas?.clientWidth || canvas?.width || 1;
-    const h = canvas?.clientHeight || canvas?.height || 1;
-    const point = pickWorld(viewer, position.x / w, position.y / h);
+  const worldAt = (event) => {
+    const rect = canvas.getBoundingClientRect();
+    const { width, height } = engine.host.size();
+    const point = pickWorld(
+      engine,
+      (event.clientX - rect.left) / (width || 1),
+      (event.clientY - rect.top) / (height || 1),
+    );
    const lon = Number(point?.lon);
    const lat = Number(point?.lat);
    return Number.isFinite(lon) && Number.isFinite(lat) ? { lon, lat } : null;
  };
-  const cameraController = () => viewer.scene.screenSpaceCameraController;
-
-  function freezeCamera() {
-    const controller = cameraController();
-    if (!controller || savedCameraInputs !== null) return;
-    savedCameraInputs = controller.enableInputs;
-    controller.enableInputs = false;
-  }
-  function thawCamera() {
-    const controller = cameraController();
-    if (controller && savedCameraInputs !== null)
-      controller.enableInputs = savedCameraInputs;
-    savedCameraInputs = null;
-  }
+  const consume = (event) => {
+    event.preventDefault?.();
+    event.stopImmediatePropagation?.();
+  };

  function endDrag() {
    anchor = null;
    corner = null;
-    thawCamera();
-    setPreview(false);
+    if (pointerId !== null && canvas.hasPointerCapture?.(pointerId))
+      canvas.releasePointerCapture(pointerId);
+    pointerId = null;
+    thaw?.();
+    thaw = null;
+    onPreview(null);
  }

-  const onDown = (event) => {
-    if (!active || destroyed || anchor) return;
-    const point = worldAt(event.position);
+  function down(event) {
+    if (
+      !active ||
+      anchor ||
+      event.button !== 0 ||
+      event.shiftKey ||
+      event.ctrlKey ||
+      event.altKey
+    )
+      return;
+    consume(event);
+    const point = worldAt(event);
    if (!point) {
      onCancel?.('sky', msg('Press on the ground, not the sky'));
      return;
    }
    anchor = point;
    corner = point;
-    freezeCamera();
-    setPreview(true);
-  };
-  const onMove = (event) => {
-    const point = anchor && !destroyed && worldAt(event.endPosition);
-    if (!point) return;
-    corner = point;
-    requestRender();
-  };
-  const onUp = (event) => {
-    if (!anchor || destroyed) return;
-    corner = worldAt(event.position) || corner;
+    pointerId = event.pointerId;
+    thaw = freezeCamera(engine.input);
+    canvas.setPointerCapture?.(pointerId);
+    onPreview(dragBox());
+  }
+  function move(event) {
+    if (!anchor || event.pointerId !== pointerId) return;
+    consume(event);
+    corner = worldAt(event) || corner;
+    onPreview(dragBox());
+  }
+  function up(event) {
+    if (!anchor || event.pointerId !== pointerId) return;
+    consume(event);
+    corner = worldAt(event) || corner;
    const box = dragBox();
    const result = validateBox(box);
    if (result.reason === 'degenerate')
      result.message = msg('Drag to size the box');
-    endDrag();
-    setActive(false);
+    stop();
    if (result.ok) onBox(result.box);
    else onCancel?.(result.reason, result.message, box);
-  };
+  }
  // Escape is taken from a document capture listener, ahead of every other
  // handler, so the interceptor runs first: when it claims the key (the
  // panel exits a live comparison), the tool stays armed and the key still
  // goes no further; otherwise Escape cancels the session.
-  const onKey = (event) => {
-    if (!active || destroyed || event.key !== 'Escape') return;
-    event.preventDefault?.();
-    event.stopImmediatePropagation?.();
-    if (onEscape?.() === true) return;
-    cancel('escape');
-  };
-
-  function bindScene() {
-    if (handler) return;
-    handler = new cesium.ScreenSpaceEventHandler(viewer.scene.canvas);
-    handler.setInputAction(onDown, cesium.ScreenSpaceEventType.LEFT_DOWN);
-    handler.setInputAction(onMove, cesium.ScreenSpaceEventType.MOUSE_MOVE);
-    handler.setInputAction(onUp, cesium.ScreenSpaceEventType.LEFT_UP);
-    const stock = viewer.screenSpaceEventHandler;
-    if (stock) {
-      savedSingleClick =
-        stock.getInputAction(cesium.ScreenSpaceEventType.LEFT_CLICK) || null;
-      savedDoubleClick =
-        stock.getInputAction(cesium.ScreenSpaceEventType.LEFT_DOUBLE_CLICK) ||
-        null;
-      stock.removeInputAction(cesium.ScreenSpaceEventType.LEFT_CLICK);
-      stock.removeInputAction(cesium.ScreenSpaceEventType.LEFT_DOUBLE_CLICK);
-    }
-    documentRef?.addEventListener?.('keydown', onKey, true);
-    documentRef?.body?.classList?.add?.('gev-imagery-box');
+  function key(event) {
+    if (!active || event.key !== 'Escape') return;
+    consume(event);
+    if (onEscape?.() !== true) cancel('escape');
  }
+  // A drag the browser takes away (a touch turned into a scroll, the window
+  // losing focus) ends the session and gives the camera back.
+  function pointerCancel(event) {
+    if (anchor && event.pointerId === pointerId) cancel('pointer-cancel');
+  }
+  const bindings = [
+    [canvas, 'pointerdown', down],
+    [documentRef, 'pointermove', move],
+    [documentRef, 'pointerup', up],
+    [documentRef, 'pointercancel', pointerCancel],
+    [documentRef, 'keydown', key],
+  ];
+  if (documentRef?.defaultView)
+    bindings.push([documentRef.defaultView, 'blur', () => cancel('blur')]);

-  function releaseScene() {
-    if (handler) {
-      handler.destroy();
-      handler = null;
-    }
-    const stock = viewer.screenSpaceEventHandler;
-    if (stock && savedSingleClick) {
-      stock.setInputAction(
-        savedSingleClick,
-        cesium.ScreenSpaceEventType.LEFT_CLICK,
-      );
-    }
-    if (stock && savedDoubleClick) {
-      stock.setInputAction(
-        savedDoubleClick,
-        cesium.ScreenSpaceEventType.LEFT_DOUBLE_CLICK,
-      );
-    }
-    savedSingleClick = null;
-    savedDoubleClick = null;
-    documentRef?.removeEventListener?.('keydown', onKey, true);
+  function stop() {
+    if (!active) return;
+    for (const [target, type, listener] of bindings)
+      target?.removeEventListener?.(type, listener, true);
+    endDrag();
+    releasePointer(lease);
+    lease = null;
+    active = false;
    documentRef?.body?.classList?.remove?.('gev-imagery-box');
-  }
-
-  function setActive(next) {
-    if (next === active) return active;
-    if (next) {
-      lease = claimPointer(IMAGERY_BOX_POINTER_OWNER);
-      if (!lease) {
-        onCancel?.(
-          'pointer-busy',
-          `${pointerOwner()} is using the pointer — close it first`,
-        );
-        return active;
-      }
-      active = true;
-      bindScene();
-    } else {
-      if (anchor) endDrag();
-      releaseScene();
-      releasePointer(lease);
-      lease = null;
-      active = false;
-    }
-    onActive?.(active);
-    return active;
+    onActive?.(false);
  }

  function cancel(reason = 'cancel') {
    if (!active || destroyed) return;
-    setActive(false);
+    stop();
    onCancel?.(reason);
  }

  return {
    /** Begin a box session. False when the pointer is held elsewhere. */
    start() {
-      return !destroyed && setActive(true);
+      if (destroyed) return false;
+      if (active) return true;
+      lease = claimPointer(IMAGERY_BOX_POINTER_OWNER);
+      if (!lease) {
+        onCancel?.(
+          'pointer-busy',
+          `${pointerOwner()} is using the pointer — close it first`,
+        );
+        return false;
+      }
+      active = true;
+      for (const [target, type, listener] of bindings)
+        target?.addEventListener?.(type, listener, true);
+      documentRef?.body?.classList?.add?.('gev-imagery-box');
+      onActive?.(true);
+      return true;
    },
    cancel,
-    isActive() {
-      return active;
-    },
-    /** Returns everything; resolves once the preview is detached. */
+    isActive: () => active,
+    /** Returns the pointer, the camera and every listener. */
    destroy() {
-      if (destroyed) return attaching;
-      if (active) setActive(false);
+      if (destroyed) return;
+      stop();
      destroyed = true;
-      releaseScene();
-      releasePointer(lease);
-      lease = null;
-      thawCamera();
-      dataSource.entities.removeAll();
-      attaching = attaching.then(() => {
-        try {
-          viewer.dataSources.remove(dataSource, true);
-        } catch {
-          /* viewer already disposed */
-        }
-      });
-      return attaching;
    },
  };
 }
@@ -12,53 +12,50 @@ import {
 } from './imageryBoxTool.js';
 import { boxToolFakes } from '../layers/recentImagery/testDoubles.mjs';

-function fixture(options = {}) {
+function fixture(options = {}, fakeOptions = {}) {
  resetPointerOwnership();
-  const fakes = boxToolFakes();
+  const fakes = boxToolFakes(fakeOptions);
  const boxes = [];
  const cancels = [];
  const actives = [];
+  const previews = [];
  const tool = initImageryBoxTool({
-    viewer: fakes.viewer,
-    cesium: fakes.cesium,
+    engine: fakes.engine,
    pickWorld: fakes.pickWorld,
    documentRef: fakes.documentRef,
    onBox: (box) => boxes.push(box),
+    onPreview: (box) => previews.push(box),
    onCancel: (reason, message) => cancels.push([reason, message]),
    onActive: (active) => actives.push(active),
    ...options,
  });
-  const camera = fakes.viewer.scene.screenSpaceCameraController;
-  const stockAction = (type) =>
-    fakes.viewer.screenSpaceEventHandler.getInputAction(fakes.types[type]);
-  const preview = () =>
-    fakes.viewer.dataSources.sources[0]?.entities.values.every((e) => e.show);
-  return {
-    ...fakes,
-    tool,
-    boxes,
-    cancels,
-    actives,
-    camera,
-    stockAction,
-    preview,
-  };
+  return { ...fakes, tool, boxes, cancels, actives, previews };
 }

-test('a session claims the pointer, borrows the stock clicks, freezes the camera only mid-drag and returns everything with the box', async () => {
+const listenerCount = (f) =>
+  f.canvas.listeners.length +
+  f.documentRef.listeners.length +
+  f.windowRef.listeners.length;
+
+test('a session claims the pointer, keeps the drag from the engine, freezes the camera only mid-drag and returns everything with the box', () => {
  const f = fixture();
  assert.equal(f.tool.start(), true);
  assert.equal(pointerOwner(), IMAGERY_BOX_POINTER_OWNER);
-  assert.equal(f.stockAction('LEFT_CLICK'), undefined);
-  assert.equal(f.stockAction('LEFT_DOUBLE_CLICK'), undefined);
  assert.ok(f.documentRef.classes.has('gev-imagery-box'));
-  assert.equal(f.camera.enableInputs, true, 'not frozen before the press');
-  f.fire('LEFT_DOWN', { position: { x: 250, y: 125 } });
-  assert.equal(f.camera.enableInputs, false);
-  assert.equal(f.preview(), true);
-  f.fire('MOUSE_MOVE', { endPosition: { x: 500, y: 250 } });
-  f.fire('MOUSE_MOVE', { endPosition: { x: 500, y: 10 } }); // sky: ignored
-  f.fire('LEFT_UP', { position: { x: 500, y: 250 } });
+  assert.equal(f.camera.inputs, true, 'not frozen before the press');
+  const press = f.down({ x: 250, y: 125 });
+  assert.equal(
+    press.prevented && press.stopped,
+    true,
+    'the press reaches no other handler (camera, clicks)',
+  );
+  assert.equal(f.camera.inputs, false);
+  assert.ok(f.captured.has(1), 'the drag holds the pointer capture');
+  assert.ok(f.previews.at(-1), 'the preview shows');
+  const drag = f.move({ x: 500, y: 250 });
+  assert.equal(drag.stopped, true);
+  f.move({ x: 500, y: 10 }); // sky: the corner stays
+  f.up({ x: 500, y: 250 });
  assert.equal(f.boxes.length, 1);
  const { west, south, east, north } = f.boxes[0];
  assert.deepEqual(
@@ -68,37 +65,49 @@ test('a session claims the pointer, borrows the stock clicks, freezes the camera
  assert.deepEqual(f.cancels, []);
  assert.equal(f.tool.isActive(), false);
  assert.equal(pointerOwner(), null);
-  assert.equal(f.stockAction('LEFT_CLICK'), f.originalClick);
-  assert.equal(f.stockAction('LEFT_DOUBLE_CLICK'), f.originalDouble);
-  assert.equal(f.camera.enableInputs, true);
-  assert.equal(f.preview(), false);
+  assert.equal(f.camera.inputs, true);
+  assert.equal(f.captured.size, 0);
+  assert.equal(f.previews.at(-1), null, 'the preview goes with the drag');
  assert.equal(f.documentRef.classes.has('gev-imagery-box'), false);
-  assert.equal(f.documentRef.listeners.length, 0);
-  assert.equal(f.handler(), null);
+  assert.equal(listenerCount(f), 0);
  assert.deepEqual(f.actives, [true, false]);
-  await f.tool.destroy();
+  f.tool.destroy();
 });

-test('a sky press, a click without a drag and Escape each say why', async () => {
+test('presses with a modifier or another button, and moves outside a drag, pass through', () => {
  const f = fixture();
  f.tool.start();
-  f.fire('LEFT_DOWN', { position: { x: 250, y: 10 } });
+  for (const fields of [{ shiftKey: true }, { ctrlKey: true }, { button: 2 }]) {
+    const press = f.down({ x: 250, y: 125 }, fields);
+    assert.equal(press.stopped, false, JSON.stringify(fields));
+  }
+  assert.equal(f.camera.inputs, true);
+  assert.equal(f.move({ x: 300, y: 200 }).stopped, false, 'a hover');
+  assert.equal(f.tool.isActive(), true);
+  f.tool.destroy();
+});
+
+test('a sky press, a click without a drag and Escape each say why', () => {
+  const f = fixture();
+  f.tool.start();
+  f.down({ x: 250, y: 10 });
  assert.deepEqual(f.cancels.at(-1), [
    'sky',
    'Press on the ground, not the sky',
  ]);
  assert.equal(f.tool.isActive(), true, 'a sky press keeps the session');
-  f.fire('LEFT_DOWN', { position: { x: 250, y: 125 } });
-  f.fire('LEFT_UP', { position: { x: 250, y: 125 } });
+  assert.equal(f.camera.inputs, true, 'and freezes nothing');
+  f.down({ x: 250, y: 125 });
+  f.up({ x: 250, y: 125 });
  assert.deepEqual(f.cancels.at(-1), ['degenerate', 'Drag to size the box']);
  f.tool.start();
  assert.equal(f.key('Escape').prevented, true);
  assert.deepEqual(f.cancels.at(-1), ['escape', undefined]);
  assert.equal(pointerOwner(), null);
-  await f.tool.destroy();
+  f.tool.destroy();
 });

-test('an Escape interceptor that claims the key leaves the tool armed; the next Escape cancels', async () => {
+test('an Escape interceptor that claims the key leaves the tool armed; the next Escape cancels', () => {
  let claim = true;
  let asked = 0;
  const f = fixture({
@@ -122,33 +131,54 @@ test('an Escape interceptor that claims the key leaves the tool armed; the next
  f.tool.start();
  f.key('Enter');
  assert.equal(asked, 2, 'other keys never reach the interceptor');
-  await f.tool.destroy();
+  f.tool.destroy();
 });

-test('a held pointer refuses the session and nothing is borrowed', async () => {
+test('a held pointer refuses the session and nothing is bound', () => {
  const f = fixture();
  const lease = claimPointer('draw');
  assert.equal(f.tool.start(), false);
  assert.deepEqual(f.cancels, [
    ['pointer-busy', 'draw is using the pointer — close it first'],
  ]);
-  assert.equal(f.stockAction('LEFT_CLICK'), f.originalClick);
-  assert.equal(f.handler(), null);
+  assert.equal(listenerCount(f), 0);
  releasePointer(lease);
  assert.equal(f.tool.start(), true);
-  await f.tool.destroy();
+  f.tool.destroy();
 });

-test('destroy mid-drag restores the camera, releases the claim and detaches the preview', async () => {
+test('destroy mid-drag restores the camera, releases the claim and clears the preview', () => {
  const f = fixture();
  f.tool.start();
-  f.fire('LEFT_DOWN', { position: { x: 250, y: 125 } });
-  assert.equal(f.viewer.dataSources.sources.length, 1);
-  await f.tool.destroy();
-  assert.equal(f.camera.enableInputs, true);
+  f.down({ x: 250, y: 125 });
+  assert.equal(f.camera.inputs, false);
+  f.tool.destroy();
+  f.tool.destroy();
+  assert.equal(f.camera.inputs, true);
  assert.equal(pointerOwner(), null);
-  assert.equal(f.viewer.dataSources.sources.length, 0);
-  assert.equal(f.stockAction('LEFT_CLICK'), f.originalClick);
+  assert.equal(f.previews.at(-1), null);
+  assert.equal(listenerCount(f), 0);
  assert.equal(f.tool.start(), false);
-  assert.equal(initImageryBoxTool({ viewer: null, onBox() {} }), null);
+  assert.equal(initImageryBoxTool({ engine: null, onBox() {} }), null);
+});
+
+test('blur and a cancelled pointer during a drag return the camera, the preview and the pointer', () => {
+  const f = fixture({}, { suspend: true });
+  f.tool.start();
+  f.down({ x: 250, y: 125 });
+  assert.equal(f.camera.suspended, 1, "the engine's counted suspension");
+  assert.equal(f.camera.inputs, true, 'the app choice is left alone');
+  f.windowRef.dispatch('blur', {});
+  assert.equal(f.camera.suspended, 0);
+  assert.equal(f.previews.at(-1), null);
+  assert.equal(pointerOwner(), null);
+  assert.equal(f.tool.isActive(), false);
+  assert.deepEqual(f.cancels.at(-1), ['blur', undefined]);
+  f.tool.start();
+  f.down({ x: 250, y: 125 });
+  f.documentRef.dispatch('pointercancel', { pointerId: 1 });
+  assert.equal(f.camera.suspended, 0);
+  assert.deepEqual(f.cancels.at(-1), ['pointer-cancel', undefined]);
+  assert.equal(listenerCount(f), 0);
+  f.tool.destroy();
 });
@@ -149,13 +149,13 @@ const cancelledResult = () => ({
 /**
 * Build the runner's area services.
 * @param {object} options
- * @param {object} options.viewer
+ * @param {object} options.engine The globe engine (view centre, credits).
 * @param {object|null} options.annotations Annotation engine.
 * @param {object} [options.placeSearch]
 * @param {object} [options.annotationResolver] The annotation outline ladder.
 */
 export function createVoiceAreas({
-  viewer,
+  engine = null,
  annotations = null,
  placeSearch = unavailablePlaceSearch,
  annotationResolver = null,
@@ -173,10 +173,10 @@ export function createVoiceAreas({

  /** The ground at the centre of the view, else the camera's position. */
  function viewCenter() {
-    const picked = annotationResolver?.pickWorldFromScreen?.(viewer, 0.5, 0.5);
+    const picked = annotationResolver?.pickWorldFromScreen?.(engine, 0.5, 0.5);
    if (Number.isFinite(picked?.lat) && Number.isFinite(picked?.lon))
      return picked;
-    const carto = viewer?.camera?.positionCartographic;
+    const carto = engine?.camera.pose().cartographic;
    return carto
      ? {
          lat: (carto.latitude * 180) / Math.PI,
@@ -223,7 +223,7 @@ export function createVoiceAreas({
    try {
      resolved = await annotationResolver.resolveAnnotationTarget({
        placeSearch,
-        viewer,
+        engine,
        target: query,
        footprint: true,
        deferFootprint: true,
@@ -405,7 +405,7 @@ export function createVoiceAreas({
        'us-census': US_CENSUS_CREDIT,
        wof: WOF_CREDIT,
      }[source];
-      if (credit) registerDynamicCredit(viewer, credit);
+      if (credit) registerDynamicCredit(engine, credit);
    },
  });

@@ -632,7 +632,7 @@ export function createVoiceAreas({
      // OpenFreeMap area holding it) is a bounded extra.
      resolved = await annotationResolver.resolveAnnotationTarget({
        placeSearch,
-        viewer,
+        engine,
        target,
        footprint: true,
        deferFootprint: true,
@@ -113,7 +113,6 @@ function fakeAnnotations() {
 function makeAreas(overrides = {}) {
  const annotations = overrides.annotations || fakeAnnotations();
  const areas = createVoiceAreas({
-    viewer: {},
    annotations,
    annotationResolver: fakeLadder(),
    findRegion: async () => null,
@@ -181,7 +180,6 @@ test('draw failures stay honest in the result, spoken line, and card', async (t)
  for (const entry of cases) {
    await t.test(entry.name, async () => {
      const areas = createVoiceAreas({
-        viewer: {},
        annotations: entry.annotations,
        annotationResolver: fakeLadder(),
        findRegion: async () => null,
@@ -732,7 +730,6 @@ test('a clear during a slow lookup is not undone by a late outline', async () =>
    release = resolve;
  });
  const areas = createVoiceAreas({
-    viewer: {},
    annotations,
    findRegion: async () => null,
    findAdminCandidates: async () => [],
@@ -781,7 +778,6 @@ test('an outlined area keeps its full geometry past store eviction', async () =>
 test('an outline from before a page reload asks to resolve again, never counts its drawing', async () => {
  const annotations = fakeAnnotations();
  const first = createVoiceAreas({
-    viewer: {},
    annotations,
    annotationResolver: fakeLadder(),
    findRegion: async () => null,
@@ -792,7 +788,6 @@ test('an outline from before a page reload asks to resolve again, never counts i
  // outline stays on the map. A mic restart keeps the runner (and handles);
  // see integrationContract.test.mjs.
  const second = createVoiceAreas({
-    viewer: {},
    annotations,
    findRegion: async () => null,
    findAdminCandidates: async () => [],
@@ -378,7 +378,7 @@ export function createGevActionRunner({
  // analyst's region/area/drawn scopes, find_imagery and osm_query all read
  // the same store.
  const voiceAreas = createVoiceAreas({
-    viewer,
+    engine,
    annotations,
    placeSearch,
    annotationResolver,
@@ -1452,7 +1452,7 @@ export function createGevActionRunner({
              runOptions,
            ),
          search: searchOsmFeatures,
-          onCredit: () => registerDynamicCredit(viewer, OSM_PLACES_CREDIT),
+          onCredit: () => registerDynamicCredit(engine, OSM_PLACES_CREDIT),
          // The listed places become the analyst's "last answer", so
          // "which of those…" filters them and never an older set.
          rememberResults: (rows, presentation, { truncated = false } = {}) => {