Tree generation

client/level/client_level.ts

@@ -38,6 +38,9 @@ export interface Chunk {
 	meshes: Partial<Record<RenderLayer, ChunkMesh>>;
 	// only for translucent meshes that have to be sorted again as the camera moves
 	translucent_sort?: TranslucentSort;
+	// blocks its generation put in neighboring chunks (leaves), as x, y, z, numeric id. kept so a neighbor that
+	// generates later, or unloads and comes back, still gets them
+	spills?: Int32Array;
 }
 
 export interface ChunkMesh {
@@ -491,7 +494,7 @@ export class ClientLevel {
 
 		let chunk = this.chunks.get(key);
 		if (chunk) {
-			// a placeholder made by a neighbor's feature, keep its blocks where generation left air
+			// blocks placed here before it generated, keep them where generation left air
 			const existing = chunk.blocks;
 			for (let i = 0; i < blocks.length; i++) {
 				if (blocks[i] !== AIR) {
@@ -503,7 +506,16 @@ export class ClientLevel {
 		}
 		chunk.generated = true;
 		chunk.dirty = true;
+		chunk.spills = spills;
 
+		// the same rules as the server (server/game/world.ts): a chunk's own blocks, then what its neighbors'
+		// features put in it, only where it has air. both ways, since the neighbors may have generated first
+		for (const [dx, dz] of ALL_NEIGHBOR_OFFSETS) {
+			const neighbor_spills = this.get_chunk(cx + dx, cz + dz)?.spills;
+			if (neighbor_spills) {
+				this.#apply_spills(neighbor_spills, chunk);
+			}
+		}
 		for (let i = 0; i < spills.length; i += 4) {
 			this.#set_block_raw(spills[i], spills[i + 1], spills[i + 2], spills[i + 3]);
 		}
@@ -583,7 +595,11 @@ export class ClientLevel {
 		}
 		const chunk_x = Math.floor(x / CHUNK_SIZE);
 		const chunk_z = Math.floor(z / CHUNK_SIZE);
-		const chunk = this.get_chunk(chunk_x, chunk_z) ?? this.add_chunk(chunk_x, chunk_z);
+		const chunk = this.get_chunk(chunk_x, chunk_z);
+		// a chunk that isn't generated yet takes it from our spills when it is
+		if (!chunk?.generated) {
+			return;
+		}
 		const lx = x - chunk_x * CHUNK_SIZE;
 		const lz = z - chunk_z * CHUNK_SIZE;
 		const index = y * CHUNK_AREA + lz * CHUNK_SIZE + lx;
@@ -594,6 +610,15 @@ export class ClientLevel {
 		}
 	}
 
+	// the spills that land in chunk
+	#apply_spills(spills: Int32Array, chunk: Chunk) {
+		for (let i = 0; i < spills.length; i += 4) {
+			if (Math.floor(spills[i] / CHUNK_SIZE) === chunk.x && Math.floor(spills[i + 2] / CHUNK_SIZE) === chunk.z) {
+				this.#set_block_raw(spills[i], spills[i + 1], spills[i + 2], spills[i + 3]);
+			}
+		}
+	}
+
 	delete_chunk_mesh(chunk: Chunk) {
 		for (const mesh of Object.values(chunk.meshes)) {
 			destroy_buffer(mesh.vertex_buffer);