workgroup size 64

Author: Sheraff

src/pages/particle-life-gpu/bin-fill.wgsl

@@ -13,7 +13,7 @@ struct Config {
 @group(1) @binding(3) var<storage, read_write> binContents: array<u32>;
 @group(2) @binding(0) var<storage, read> particlePositions: array<vec2f>;
 
-@compute @workgroup_size(256)
+@compute @workgroup_size(64)
 fn clear(
 	@builtin(global_invocation_id) id: vec3u,
 ) {
@@ -26,7 +26,7 @@ fn clear(
 	atomicStore(&binCursor[i], 0u);
 }
 
-@compute @workgroup_size(256)
+@compute @workgroup_size(64)
 fn size(
 	@builtin(global_invocation_id) id: vec3u,
 ) {
@@ -43,7 +43,7 @@ fn size(
 	atomicAdd(&binSize[index], 1u);
 }
 
-@compute @workgroup_size(256)
+@compute @workgroup_size(64)
 fn prepare(
 	@builtin(global_invocation_id) id: vec3u,
 ) {
@@ -58,7 +58,7 @@ fn prepare(
 	binOffset[i] = offset;
 }
 
-@compute @workgroup_size(256)
+@compute @workgroup_size(64)
 fn fill(
 	@builtin(global_invocation_id) id: vec3u,
 ) {

src/pages/particle-life-gpu/index.tsx

@@ -79,7 +79,7 @@ async function start(
 	const width = ctx.canvas.width
 	const height = ctx.canvas.height
 
-	const repulsionRange = 25
+	const repulsionRange = 35
 	const attractionRange = 26
 	const repulsionStrength = 30
 	const attractionStrength = 30
@@ -90,7 +90,7 @@ async function start(
 	const toBinX = widthDivisions / width
 	const toBinY = heightDivisions / height
 	const binCount = widthDivisions * heightDivisions
-	// const particleCount = 130_000
+	// const particleCount = 200_000
 	const particleCount = 100_000
 	// const particleCount = 20_000
 
@@ -331,16 +331,16 @@ async function start(
 		pass.setBindGroup(0, binConfigBindGroup)
 		pass.setBindGroup(1, binBindGroup)
 		pass.setBindGroup(2, particlePositionBindGroup)
-		pass.dispatchWorkgroups(Math.ceil(binCount / 256))
+		pass.dispatchWorkgroups(Math.ceil(binCount / 64))
 
 		pass.setPipeline(binSizePipeline)
-		pass.dispatchWorkgroups(Math.ceil(particleCount / 256))
+		pass.dispatchWorkgroups(Math.ceil(particleCount / 64))
 
 		pass.setPipeline(binPreparePipeline)
-		pass.dispatchWorkgroups(Math.ceil(binCount / 256))
+		pass.dispatchWorkgroups(Math.ceil(binCount / 64))
 
 		pass.setPipeline(binFillPipeline)
-		pass.dispatchWorkgroups(Math.ceil(particleCount / 256))
+		pass.dispatchWorkgroups(Math.ceil(particleCount / 64))
 
 		pass.end()
 
@@ -519,7 +519,7 @@ async function start(
 		pass.setBindGroup(2, updateConfigBindGroup)
 		pass.setBindGroup(3, updateBinsBindGroup)
 
-		pass.dispatchWorkgroups(Math.ceil(particleCount / 256))
+		pass.dispatchWorkgroups(Math.ceil(particleCount / 64))
 
 		pass.end()
 		const commandBuffer = encoder.finish()
@@ -633,6 +633,7 @@ async function start(
 		device.queue.submit([commandBuffer])
 	}
 
+	let frameCount = 0
 	let playing = document.visibilityState === 'visible'
 	let lastTime = performance.now()
 	let rafId = requestAnimationFrame(function frame(time) {
@@ -641,8 +642,12 @@ async function start(
 		if (!playing) return
 		const dt = time - lastTime
 		lastTime = time
+		frameCount++
 		onFrame(dt)
-		computeBins()
+		if (frameCount > 10) {
+			computeBins()
+			frameCount = 0
+		}
 		updateParticles(dt / 1000)
 		drawParticles()
 	})

src/pages/particle-life-gpu/update.wgsl

@@ -31,7 +31,7 @@ struct Config {
 
 const COLOR_COUNT = 6u;
 
-@compute @workgroup_size(256)
+@compute @workgroup_size(64)
 fn update(
 	@builtin(global_invocation_id) id: vec3u,
 ) {
@@ -57,6 +57,8 @@ fn update(
 	let half_width = config.width / 2.0;
 	let half_height = config.height / 2.0;
 
+	// var total_count = 0u;
+
 	for (var bin_x = min_bin_x; bin_x <= max_bin_x; bin_x++) {
 		let wrapped_bin_x = (bin_x + wd) % wd;
 		for (var bin_y = min_bin_y; bin_y <= max_bin_y; bin_y++) {
@@ -99,17 +101,23 @@ fn update(
 					let other_color = particleColors[other_index];
 					let interaction_index = color * COLOR_COUNT + other_color;
 					let interaction_strength = interactions[interaction_index];
+					// if (interaction_strength > 0.0) {
+					// 	total_count += 1u;
+					// }
 					let normalized_distance = (config.attractionRange - (dist - config.repulsionRange)) / config.attractionRange;
 					let symmetric_distance = 1.0 - abs(normalized_distance * 2.0 - 1.0);
 					let strength = symmetric_distance * interaction_strength * config.attractionStrength * dt;
+					// if (total_count > 200u) {
+					// 	strength = strength * (200.0 / f32(total_count));
+					// }
 					velocity += normalize(offset) * strength;
 				}
 			}
 		}
 	}
 
 	// dampen velocity
-	velocity -= velocity * 8 * dt;
+	velocity -= vec2f(velocity.x * velocity.x * sign(velocity.x), velocity.y * velocity.y * sign(velocity.y)) * 0.2 * dt;
 
 	// update position
 	position += velocity * dt;

src/router.ts

@@ -236,7 +236,7 @@ export const ROUTES = {
 			image: particle_life_gpu_image
 		},
 		git: {
-			lastModified: 1762613219000,
+			lastModified: 1762619297000,
 			firstAdded: 1762551884000
 		},
 	},