feat: add Nepal flood incident scene

src/overlays/worldOverlay.js

@@ -103,6 +103,7 @@ export const WORLD_OVERLAY_OCCLUDER_SELECTORS = Object.freeze([
   '#space-mission-panel',
   '#space-mission-panel-host',
   '#military-awareness-panel',
+  '#bhote-koshi-event-panel',
   // Cockpit: solid backdrop-filled windows only (both bounded to
   // `min(340px, 28vw)` wide and `min(42vh, 410px)` tall, both `hidden` until
   // toggled). Every other cockpit selector was removed — see the block comment.
@@ -460,7 +461,20 @@ export function normalizeOverlayEntry(sourceId, entry) {
     edgeFade: entry.edgeFade === false || entry.edgeFade === 'none' ? 'none' : 'keyhole',
     horizonCull: entry.horizonCull !== false,
     terrainOcclusion: entry.terrainOcclusion === true,
-    sourceAlpha: clamp01(entry.sourceAlpha ?? entry.alpha, 1),
+    sourceAlpha: typeof (entry.sourceAlpha ?? entry.alpha) === 'function'
+      ? (entry.sourceAlpha ?? entry.alpha)
+      : clamp01(entry.sourceAlpha ?? entry.alpha, 1),
+    presentationScale: typeof entry.presentationScale === 'function'
+      ? entry.presentationScale
+      : Math.max(0, Number(entry.presentationScale) || 1),
+    leaderProgress: typeof entry.leaderProgress === 'function'
+      ? entry.leaderProgress
+      : clamp01(entry.leaderProgress, 1),
+    contentAlpha: typeof entry.contentAlpha === 'function'
+      ? entry.contentAlpha
+      : clamp01(entry.contentAlpha, 1),
+    anchorDot: entry.anchorDot === true,
+    leaderStyle: entry.leaderStyle === 'elbow' ? 'elbow' : 'straight',
     temporalAlpha: clamp01(entry.temporalAlpha, 1),
     gapPx: Number.isFinite(Number(entry.gapPx)) ? Math.max(0, Number(entry.gapPx)) : 12,
     leaderOffsetPx: Number.isFinite(Number(entry.leaderOffsetPx))
@@ -1513,6 +1527,8 @@ function getProjectionRecord(entry) {
       candidate: null,
       distanceAlpha: 1,
       paintScale: 1,
+      leaderProgress: 1,
+      contentAlpha: 1,
       altitudeAlpha: 1,
       sourceAlpha: 1,
       protectedPlacement: null,
@@ -1575,6 +1591,30 @@ function resetFrameDomains() {
   }
 }
 
+// Evaluate optional scene presentation outside the shared projection hot path.
+// Passing records (rather than intermediate doubles) also avoids boxing the
+// ordinary moving-source workload at a non-inlined call boundary.
+function applyPresentation(entry, source, record) {
+  try {
+    const scale = Number(typeof entry.presentationScale === 'function'
+      ? entry.presentationScale() : entry.presentationScale);
+    record.paintScale *= Number.isFinite(scale) ? Math.max(0, scale) : 1;
+    const alpha = Number(typeof entry.sourceAlpha === 'function'
+      ? entry.sourceAlpha() : entry.sourceAlpha);
+    record.sourceAlpha = source.options.alpha
+      * (Number.isFinite(alpha) ? Math.max(0, Math.min(1, alpha)) : 1);
+    const leader = Number(typeof entry.leaderProgress === 'function'
+      ? entry.leaderProgress() : entry.leaderProgress);
+    record.leaderProgress = Number.isFinite(leader) ? Math.max(0, Math.min(1, leader)) : 1;
+    const content = Number(typeof entry.contentAlpha === 'function'
+      ? entry.contentAlpha() : entry.contentAlpha);
+    record.contentAlpha = Number.isFinite(content) ? Math.max(0, Math.min(1, content)) : 1;
+    return true;
+  } catch {
+    return false;
+  }
+}
+
 function snapshotAndProject(entry, source, viewProjection, keyhole) {
   const record = getProjectionRecord(entry);
   let position;
@@ -1651,7 +1691,14 @@ function snapshotAndProject(entry, source, viewProjection, keyhole) {
   record.altitudeAlpha = entry.altitudeFadeEnd === Number.POSITIVE_INFINITY
     ? (Number.isFinite(cameraAltitude) && cameraAltitude < entry.minAltitude ? 0 : 1)
     : altitudeFade(cameraAltitude, record.altitudeOptions);
-  record.sourceAlpha = source.options.alpha * entry.sourceAlpha;
+  record.leaderProgress = 1;
+  record.contentAlpha = 1;
+  if (entry.presentationScale !== 1 || entry.leaderProgress !== 1
+    || entry.contentAlpha !== 1 || typeof entry.sourceAlpha === 'function') {
+    if (!applyPresentation(entry, source, record)) return null;
+  } else {
+    record.sourceAlpha = source.options.alpha * entry.sourceAlpha;
+  }
   if (record.distanceAlpha <= 0 || record.paintScale <= 0
     || record.altitudeAlpha <= 0 || record.sourceAlpha <= 0) return null;
 
@@ -2075,7 +2122,14 @@ function paintEntryItem(item, keyhole) {
     * record.distanceAlpha * record.altitudeAlpha * keyholeAlpha;
   if (finalAlpha <= 0.001) return;
   if (record.paintScale === 1) {
-    paintOverlayEntry(_ctx, entry, placement, finalAlpha);
+    paintOverlayEntry(
+      _ctx,
+      entry,
+      placement,
+      finalAlpha,
+      record.leaderProgress,
+      record.contentAlpha,
+    );
   } else {
     const scaled = localizeScaledPlacement(
       placement,
@@ -2085,7 +2139,14 @@ function paintEntryItem(item, keyhole) {
     _ctx.save();
     _ctx.translate(placement.rect.x, placement.rect.y);
     _ctx.scale(record.paintScale, record.paintScale);
-    paintOverlayEntry(_ctx, entry, scaled, finalAlpha);
+    paintOverlayEntry(
+      _ctx,
+      entry,
+      scaled,
+      finalAlpha,
+      record.leaderProgress,
+      record.contentAlpha,
+    );
     _ctx.restore();
   }
   publishPaintRect(item);