WIP acceleration structure API proposal

examples/Cargo.toml

@@ -34,13 +34,18 @@ path = "mesh-shading/main.rs"
 name = "bench"
 path = "bench/main.rs"
 
+[[bin]]
+name = "ray-tracing"
+path = "ray-tracing/main.rs"
+
 [dependencies]
 image = "0.23.12"
 log = "0.4"
 hal = { path = "../src/hal", version = "0.8", package = "gfx-hal" }
 auxil = { path = "../src/auxil/auxil", version = "0.9", package = "gfx-auxil" }
 gfx-backend-empty = { path = "../src/backend/empty", version = "0.8" }
 winit = { version = "0.24", features = ["web-sys"] }
+cgmath = "0.18.0"
 
 [target.'cfg(not(target_arch = "wasm32"))'.dependencies]
 env_logger = "0.8"

examples/ray-tracing/README.md

@@ -0,0 +1,7 @@
+# Ray Tracing
+
+TODO
+
+- Screenshot
+- Explain which backends this supports
+- Explain what hardware this supports

examples/ray-tracing/build-shaders.ps1

@@ -0,0 +1,11 @@
+$shaders = @(
+    "$PSScriptRoot\data\simple.rchit"
+    "$PSScriptRoot\data\simple.rgen"
+    "$PSScriptRoot\data\simple.rmiss"
+)
+
+Remove-Item $PSScriptRoot\data\*.spv
+
+foreach ($shader in $shaders) {
+    & glslangValidator --target-env vulkan1.2 --entry-point main $shader -o "$shader.spv"
+}

examples/ray-tracing/data/simple.rchit

@@ -0,0 +1,9 @@
+#version 460
+#extension GL_EXT_ray_tracing : enable
+
+layout(location = 0) rayPayloadInEXT vec3 out_color;
+hitAttributeEXT vec3 attribs;
+
+void main() {
+  out_color = vec3(1.0, 0.0, 0.0);
+}

examples/ray-tracing/data/simple.rgen

@@ -0,0 +1,34 @@
+#version 460
+#extension GL_EXT_ray_tracing : enable
+
+layout(binding = 0, set = 0) uniform accelerationStructureEXT accel_struct;
+layout(binding = 1, set = 0, rgba8) uniform image2D storage_image;
+layout(binding = 2, set = 0) uniform CameraProperties {
+  mat4 view_inverse;
+  mat4 proj_inverse;
+}
+cam;
+
+layout(location = 0) rayPayloadEXT vec3 out_color;
+
+void main() {
+  const vec2 pixel_center = vec2(gl_LaunchIDEXT.xy) + vec2(0.5);
+  const vec2 in_uv = pixel_center / vec2(gl_LaunchSizeEXT.xy);
+  vec2 d = in_uv * 2.0 - 1.0;
+
+  vec4 origin = cam.view_inverse * vec4(0, 0, 0, 1);
+  vec4 target = cam.proj_inverse * vec4(d.x, d.y, 1, 1);
+  vec4 direction = cam.view_inverse * vec4(normalize(target.xyz), 0);
+
+  out_color = vec3(0.0);
+
+  origin.xyz = vec3(0, 0, 1);
+  direction.xyz = vec3(0, 0, -1);
+
+  float tmin = 0.001;
+  float tmax = 10000.0;
+  traceRayEXT(accel_struct, gl_RayFlagsOpaqueEXT, 0xff, 0, 0, 0, origin.xyz,
+              tmin, direction.xyz, tmax, 0);
+
+  imageStore(storage_image, ivec2(gl_LaunchIDEXT.xy), vec4(out_color, 1.0));
+}

examples/ray-tracing/data/simple.rmiss

@@ -0,0 +1,6 @@
+#version 460
+#extension GL_EXT_ray_tracing : enable
+
+layout(location = 0) rayPayloadInEXT vec3 out_color;
+
+void main() { out_color = vec3(0.8, 0.8, 0.8); }