fix(voxel-renderer): drain empty VoxelLayer (#239)

Author: fraxken

.changeset/tame-camels-switch.md

@@ -0,0 +1,5 @@
+---
+"@jolly-pixel/voxel.renderer": patch
+---
+
+Drain and remove empty VoxelLayer

packages/voxel-renderer/src/world/VoxelLayer.ts

@@ -73,6 +73,7 @@ export class VoxelLayer {
   #visible: boolean;
   #chunks = new Map<string, VoxelChunk>();
   #chunkSize: number;
+  #pendingRemoval: VoxelChunk[] = [];
 
   constructor(
     options: VoxelLayerOptions
@@ -235,6 +236,7 @@ export class VoxelLayer {
       this.#chunks.delete(
         this.#createChunkKey(cx, cy, cz)
       );
+      this.#pendingRemoval.push(chunk);
     }
   }
 
@@ -320,6 +322,12 @@ export class VoxelLayer {
     yield* this.#chunks.values();
   }
 
+  * drainPendingRemovals(): IterableIterator<VoxelChunk> {
+    while (this.#pendingRemoval.length > 0) {
+      yield this.#pendingRemoval.pop()!;
+    }
+  }
+
   get chunkCount(): number {
     return this.#chunks.size;
   }

packages/voxel-renderer/src/world/VoxelWorld.ts

@@ -399,6 +399,14 @@ export class VoxelWorld {
         yield { layer, chunk };
       }
     } while (this.#layersToRemove.length > 0);
+
+    // Drain individual chunks that became empty this frame.
+    // Their Three.js meshes must be removed even though the layer is still active.
+    for (const layer of this.#layers) {
+      for (const chunk of layer.drainPendingRemovals()) {
+        yield { layer, chunk };
+      }
+    }
   }
 
   clear(): void {