Raytraced baking stubs

Shaders/raytrace/src/build.bat

@@ -1 +1,2 @@
-.\dxc.exe -Zpr -Fo ..\raytrace.cso -T lib_6_3 .\raytrace.hlsl
+.\dxc.exe -Zpr -Fo ..\raytrace.cso -T lib_6_3 .\raytrace.hlsl
+.\dxc.exe -Zpr -Fo ..\raytrace_bake.cso -T lib_6_3 .\raytrace_bake.hlsl

Shaders/raytrace/src/raytrace_bake.hlsl

@@ -0,0 +1,129 @@
+
+struct Vertex {
+	float3 position;
+	float3 normal;
+	float2 tex;
+};
+
+struct RayGenConstantBuffer {
+	float4 v0; // frame
+	float4 v1;
+	float4 v2;
+	float4 v3;
+	float4 v4;
+};
+
+struct RayPayload {
+	float4 color;
+	float3 ray_origin;
+	float3 ray_dir;
+};
+
+RWTexture2D<float4> render_target : register(u0);
+RaytracingAccelerationStructure scene : register(t0);
+ByteAddressBuffer indices : register(t1);
+StructuredBuffer<Vertex> vertices : register(t2);
+ConstantBuffer<RayGenConstantBuffer> constant_buffer : register(b0);
+
+Texture2D<float4> mytexture0 : register(t3);
+Texture2D<float4> mytexture1 : register(t4);
+Texture2D<float4> mytexture2 : register(t5);
+Texture2D<float4> mytexture_env : register(t6);
+
+static uint seed;
+
+uint wang_hash(uint seed) {
+	seed = (seed ^ 61) ^ (seed >> 16);
+	seed *= 9;
+	seed = seed ^ (seed >> 4);
+	seed *= 0x27d4eb2d;
+	seed = seed ^ (seed >> 15);
+	return seed;
+}
+
+void compute_seed(uint index, uint iteration, uint depth) {
+	seed = uint(wang_hash((1 << 31) | (depth << 22) | iteration) ^ wang_hash(index));
+}
+
+float rand() {
+	static const float png_01_convert = (1.0f / 4294967296.0f);
+	seed ^= uint(seed << 13);
+	seed ^= uint(seed >> 17);
+	seed ^= uint(seed << 5);
+	return float(seed * png_01_convert);
+}
+
+float3 cos_weighted_random_hemisphere_direction(float3 n) {
+	float2 r = float2(rand(), rand());
+	float3 uu = normalize(cross(n, float3(0.0, 1.0, 1.0)));
+	float3 vv = cross(uu, n);
+	float ra = sqrt(r.y);
+	float rx = ra * cos(6.2831 * r.x); 
+	float ry = ra * sin(6.2831 * r.x);
+	float rz = sqrt(1.0 - r.y);
+	float3 rr = float3(rx * uu + ry * vv + rz * n);
+	return normalize(rr);
+}
+
+[shader("raygeneration")]
+void raygeneration() {
+
+	uint id = DispatchRaysIndex().x + DispatchRaysDimensions().x * DispatchRaysIndex().y;
+	compute_seed(id, constant_buffer.v0.x, 0);
+
+	float2 xy = DispatchRaysIndex().xy + 0.5f;
+	xy.x += rand(); // AA
+	xy.y += rand();
+
+	float3 pos = mytexture0.Load(uint3(xy, 0)).rgb;
+	float3 nor = mytexture1.Load(uint3(xy, 0)).rgb;
+
+	float color = 0.0;
+
+	for (int i = 0; i < 4; ++i) {
+		RayPayload payload;
+		payload.ray_origin = pos;
+		payload.ray_dir = cos_weighted_random_hemisphere_direction(nor);
+
+		RayDesc ray;
+		ray.TMin = 0.01;
+		ray.TMax = 10.0;
+		ray.Origin = payload.ray_origin;
+		ray.Direction = payload.ray_dir;
+
+		TraceRay(scene, RAY_FLAG_FORCE_OPAQUE, ~0, 0, 1, 0, ray, payload);
+		color += payload.color.r;
+
+		compute_seed(id, constant_buffer.v0.x, i);
+	}
+
+	color /= 4;
+	color = 1 - color;
+	render_target[DispatchRaysIndex().xy] = float4(color.xxx, 0.0f);
+}
+
+float3 hit_world_position() {
+	return WorldRayOrigin() + RayTCurrent() * WorldRayDirection();
+}
+
+float3 hit_attribute(float3 vertexAttribute[3], BuiltInTriangleIntersectionAttributes attr) {
+	return vertexAttribute[0] +
+		attr.barycentrics.x * (vertexAttribute[1] - vertexAttribute[0]) +
+		attr.barycentrics.y * (vertexAttribute[2] - vertexAttribute[0]);
+}
+
+float2 hit_attribute2d(float2 vertexAttribute[3], BuiltInTriangleIntersectionAttributes attr) {
+	return vertexAttribute[0] +
+		attr.barycentrics.x * (vertexAttribute[1] - vertexAttribute[0]) +
+		attr.barycentrics.y * (vertexAttribute[2] - vertexAttribute[0]);
+}
+
+[shader("closesthit")]
+void closesthit(inout RayPayload payload, in BuiltInTriangleIntersectionAttributes attr) {
+	payload.color = float4(1,1,1,0);
+}
+
+[shader("miss")]
+void miss(inout RayPayload payload) {
+	payload.color = float4(0,0,0,-1);
+}