Keep Navara cinematic clouds visible at flight altitudes

src/globe/navara/look.js

@@ -164,7 +164,7 @@ export function buildNavaraLook(
       }
     }
     // Terrain-relative layers keep distant cumulus above mountain ridges.
-    // Keep a downward view clear once the camera rises above the cloud deck.
+    // Keep the deck visible from aircraft altitude, then clear it for regional views.
     if (clouds) {
       const offset = cloudTerrainOffset(height, ground);
       const pass = clouds.ref?.raw;
@@ -179,7 +179,7 @@ export function buildNavaraLook(
         }
       }
       cloudsSunlit = cloudsSunlitAt(elevation, cloudsSunlit);
-      const ceiling = CUMULUS_BASES[0] + offset + (cloudsShown ? 800 : 500);
+      const ceiling = offset + (cloudsShown ? 12_000 : 11_000);
       const next = cloudsSunlit && height <= ceiling;
       if (next !== cloudsShown) {
         cloudsShown = next;

src/globe/navara/look.test.mjs

@@ -143,6 +143,8 @@ test('cumulus rises over mountain terrain and leaves the orbital view clear', ()
   assert.deepEqual(clouds.updates, [{ visible: false }]);
   look.frame(900, false, 0);
   assert.deepEqual(clouds.updates.at(-1), { visible: true });
+  look.frame(6500, true, 0);
+  assert.deepEqual(clouds.updates.at(-1), { visible: true }, 'above the deck');
 });
 
 test('globe lighting switches on only at rest, and off even in motion', () => {

src/globe/navara/viewOptions.js

@@ -83,7 +83,7 @@ export function globeLightingAt(height, current = false) {
 // Navara cloud layers use ellipsoid heights. Over uplands raise the two
 // cumulus layers together; at world scale a single ground sample no longer
 // represents the whole view. Quantize the offset to avoid tiny layer updates.
-export const LOCAL_CLOUD_COVERAGE = 0.22;
+export const LOCAL_CLOUD_COVERAGE = 0.36;
 export const CUMULUS_BASES = Object.freeze([1500, 1800]);
 export function cloudTerrainOffset(height, ground) {
   if (!Number.isFinite(ground) || height >= STARS_SPACE_ENTER_M) return 0;

src/globe/navara/viewOptions.test.mjs

@@ -102,7 +102,7 @@ test('the cinematic look: photoreal plus clouds and ACES, no sun shadow maps, no
     useNormalBuffer: false,
     albedoScale: 2,
   });
-  assert.equal(clouds.clouds.coverage, 0.22);
+  assert.equal(clouds.clouds.coverage, 0.36);
   assert.equal(clouds.clouds.shadows, false, 'no cloud shadow maps');
   assert.ok(
     clouds.clouds.cloudLayers.every(({ altitude }) => altitude >= 1000),