First Commit

shaders/findGridHashRanges.wgsl

@@ -0,0 +1,40 @@
+@group(0) @binding(0)
+var<storage, read> gridHashes: array<u32>;
+
+@group(0) @binding(1)
+var<storage, read> indices: array<u32>;
+
+@group(0) @binding(2)
+var<storage, read_write> startIndices: array<u32>;
+
+@group(0) @binding(3)
+var<storage, read_write> endIndices: array<u32>;
+
+@group(0) @binding(4)
+var<uniform> totalCount: u32;
+
+@compute @workgroup_size(256)
+fn findStartEndIndices(@builtin(global_invocation_id) globalId: vec3<u32>) {
+
+	let i = globalId.x;
+
+	if (i >= totalCount) {
+		return;
+	}
+	
+	let currentHash		= gridHashes[i];
+
+	if (i == 0u || gridHashes[i - 1u] != currentHash) {
+
+		startIndices[currentHash] = i;
+
+	}
+
+
+	if (i == totalCount - 1u || gridHashes[i + 1u] != currentHash) {
+
+		endIndices[currentHash] = i;
+		
+	}
+
+}