fix: stabilize particle visibility across zoom levels

2026-09-05 11:20:33 +08:00
parent 067bfdc38b
commit f926a3f007
6 changed files with 141 additions and 33 deletions
--- a/include/mbgl/shaders/gl/particle_gpu_validation.hpp
+++ b/include/mbgl/shaders/gl/particle_gpu_validation.hpp
@@ -201,7 +201,9 @@ void main() {
            float maxAge = u_marker.z * mix(0.75, 1.25, lifecycleHash);
            float initialAgeHash = particleHash(v_uv + vec2(71.19, 29.47));
            bool respawn = initialSeed;
-            float age = initialSeed ? initialAgeHash * maxAge : previous.b + u_pass.y;
+            // Lifecycle is wall-clock based: zoom-aware visual advection and
+            // forecast playback must not change respawn cadence.
+            float age = initialSeed ? initialAgeHash * maxAge : previous.b + u_pass.w;
            vec2 position = previous.rg;
            vec2 velocity;
            bool valid = !respawn && fieldVelocityAt(position, velocity);