migrate gpu puzzles to its own repo https://github.com/AnswerDotAI/gpu-browser-app

Author: austinvhuang

examples/hello_world/Makefile

@@ -20,7 +20,7 @@ run_setup: check-python
 	cd $(GPUCPP) && python3 setup.py
 
 build/$(TARGET): run.cpp
-	mkdir -p build && $(CXX) $(FLAGS) -DNDEBUG -o ./build/$(TARGET)
+	mkdir -p build && $(CXX) $(FLAGS) -DNO_LOG -o ./build/$(TARGET)
 
 debug: run.cpp
 	mkdir -p build && $(CXX) $(FLAGS) -g -o ./build/$(TARGET)

examples/shadertui/shader.wgsl

@@ -2,30 +2,60 @@
 @group(0) @binding(1) var<uniform> params: Params;
 
 struct Params {
-  time: f32,
-  screenwidth: u32,
-  screenheight: u32,
+    time: f32,
+    screenwidth: u32,
+    screenheight: u32,
 };
 
-fn sdf(p: vec2<f32>, c: vec2<f32>, r: f32) -> f32 {
-  // Signed distance function (SDF) for a circle
-  // See https://iquilezles.org/articles/distfunctions2d/
-  return length(p - c) - r;
+struct Particle {
+    position: vec2<f32>,
+    velocity: vec2<f32>,
+    life: f32,
 }
 
-@compute @workgroup_size(16, 16, 1)
-fn main(@builtin(global_invocation_id) globalID : vec3<u32>) {
+const NUM_PARTICLES: u32 = 1000u;
+const PARTICLE_LIFE: f32 = 9.0;
+const EMISSION_RATE: f32 = 300.0;
 
-  // Normalize xy coordinates
-  let xy: vec2<f32> =
-    vec2<f32>(f32(globalID.x) / f32(params.screenwidth),
-              f32(globalID.y) / f32(params.screenheight));
-
-  // 1-D index into the output GPU buffer
-  let idx = globalID.y * params.screenwidth + globalID.x;
+fn rand(n: f32) -> f32 {
+    return fract(sin(n) * 43758.5453123);
+}
 
-  // Draw a circle, oscillating with time
-  let position = vec2<f32>(0.5, 0.5 + 0.1 * sin(3.0 * params.time));
-  out[idx] = 0.3 - min(5 * abs(sdf(xy, position, 0.2)), 0.3);
+fn initialize_particle(id: f32, time: f32) -> Particle {
+    let random1 = rand(id * 0.01 + time * 0.1);
+    let random2 = rand(id * 0.02 + time * 0.1);
+    let angle = random1 * 2.0 * 3.14159;
+    let speed = 0.05 + random2 * 0.05;
+    
+    return Particle(
+        vec2<f32>(0.5, 0.5),
+        vec2<f32>(cos(angle) * speed, sin(angle) * speed),
+        PARTICLE_LIFE
+    );
+}
 
+@compute @workgroup_size(16, 16, 1)
+fn main(@builtin(global_invocation_id) globalID : vec3<u32>) {
+    let resolution = vec2<f32>(f32(params.screenwidth), f32(params.screenheight));
+    let uv = vec2<f32>(f32(globalID.x) / resolution.x, f32(globalID.y) / resolution.y);
+    let idx = globalID.y * params.screenwidth + globalID.x;
+    
+    var color: f32 = 0.0;
+    
+    for (var i: f32 = 0.0; i < f32(NUM_PARTICLES); i += 1.0) {
+        let spawn_time = i / EMISSION_RATE;
+        let particle_age = fract((params.time - spawn_time) / PARTICLE_LIFE) * PARTICLE_LIFE;
+        
+        if (particle_age < PARTICLE_LIFE) {
+            var particle = initialize_particle(i, spawn_time);
+            particle.position += particle.velocity * particle_age;
+            
+            let distance = length(uv - particle.position);
+            if (distance < 0.005) {
+                color += 0.5 * (1.0 - particle_age / PARTICLE_LIFE);
+            }
+        }
+    }
+    
+    out[idx] = min(color, 1.0);
 }