Layers are to draw through the globe contract on both engines, so Cesium
gets back the movers and lines removed as unused:
- engine.movers draws sprite sets as a BillboardCollection (atlas cells
cropped once per set), point sets as a PointPrimitiveCollection and
model sets as one Model per instance. depthTest, disableWithinM, order,
scaleByDistance, colorBlend, unlit and minimumPixelSize follow the
contract; a model's matrix is written in place, so instances no longer
share one scratch matrix.
- engine.lines draws each line as a polyline Primitive with width in CSS
px, geodesic arcs, dashes, the tactical and arrow materials,
depthFailAlpha and modelMatrix; a rebuild keeps its show, matrix,
colour and place in order.
- The picker returns the pickId a layer wrote last, skips sets that are
not pickable and instances behind the horizon, and falls through to
what lies under them. Surface samples can exclude mover sets again.
movers and lines move from the optional capabilities into the required
contract shape, and the contract suite always runs their checks.
- src/geo drops the ported debug argument checks and the tests that
bitExact already covers; package boundaries accept a directory entry,
so src/geo/ is listed once per group.
- Cesium no longer carries movers and lines nobody draws with: they are
optional engine capabilities. The fake engine and the Cesium camera use
the shared cameraMath; unused contract tables, clock.ticked, the
'finest' surface detail and Navara click statistics are gone.
- ALPR keeps one overlay core and one presentation model for both
engines, bikeshare one station bookkeeping, the Navara ground effects
one definition helper; image atlases, view centres, mover banks and
colours are shared.
- The legacy switch route, the clock offset and rate controls and other
unused exports are removed.
- The acceptance runs the Navara draw, geo import and scope checks;
scenarios use the harness switch and page helpers; the main chunk
check keeps the size budget only and runs once in CI.
engine.surface.sampleHeightDetailed(place, { exclude, lod }) answers
{ height, source: 'tiles' | 'terrain', tileSizeM? } (src/globe/surfaceDetail.js).
On Navara tileSizeM is the extent of the tile that answered and
lod 'finest' takes the finest loaded tile, drawn or not; Cesium answers
tiles without a size, else the globe's terrain. acceptedSurfaceHeight()
turns an answer into a height or a miss: tiles larger than
MAX_FLOOR_TILE_SIZE_M (4 km) are too coarse, terrain is not the mesh.
The mesh floor sampler and the ground snap are engine-only now (a viewer
or scene reaches its engine through engineFromViewer, which also registers
the scene) and treat a coarse answer as a miss, as they treat undefined.
Measured on Navara at Austin: while the tiles stream, a 27.9 km tile reads
143.2 m where the ground is 122.5 m (a 1.8 km tile).
`exclude` takes the engine's own mover sets (MoverSet.id): Cesium hides a
set's primitive for the synchronous sample (Cesium matches excluded objects
per billboard, not per collection); Navara's ray only meets tiles.
"sampleHeight undefined in the app on Navara" did not reproduce: the
startup Austin sample is 121.9 m (tile 889 m) on Navara and 122.4 m on
Cesium; one ModelMesh class is patched.
S2 QA (scripts/qa-surface-heights.mjs, 20 places at JFK, SFO, AUS, roofs
and streets): Navara within 2 m of Cesium at 19/20 from 800 m and 18/20
from 15 km with lod 'finest' (gates 18 and 15); offsets per region
-0.21 / +0.4 / +0.1 m; the Empire State roof differs by 39 m (spire
geometry). Navara tile sizes at 800 m: 112-314 m.
createCesiumEngine wraps an existing viewer without changing it: camera, picker, projector, frames, render (through the render governor), surface, input, credits and maps, with geo values out and Cesium values in at the boundary. Map and surface code is shared with src/maps and services/groundSnap instead of copied. scripts/qa-globe-contract.mjs runs the contract suite against the engine in headless Chrome; the camera-events check now waits for the previous move to end, as Cesium's moveStart marks a move from rest.
German Khokhlov