From d3a2617d7fdc255e78e253582ebcd9344b8659be Mon Sep 17 00:00:00 2001 From: Dynamitos Date: Tue, 31 Dec 2024 10:40:03 +0100 Subject: [PATCH] refactor ray tracing --- res/shaders/raytracing/ClosestHit.slang | 107 ++++++++++++++++-- res/shaders/raytracing/Miss.slang | 11 +- res/shaders/raytracing/RayGen.slang | 114 ++------------------ res/shaders/raytracing/RayTracingData.slang | 27 ++--- 4 files changed, 127 insertions(+), 132 deletions(-) diff --git a/res/shaders/raytracing/ClosestHit.slang b/res/shaders/raytracing/ClosestHit.slang index e7e14e0..fe282ff 100644 --- a/res/shaders/raytracing/ClosestHit.slang +++ b/res/shaders/raytracing/ClosestHit.slang @@ -12,6 +12,10 @@ import MATERIAL_FILE_NAME; [shader("closesthit")] void closestHit(inout RayPayload hitValue, in BuiltInTriangleIntersectionAttributes attr) { + hitValue.hit = true; + // todo: replace with anyhit shader + if(hitValue.anyHit) + return; const float3 barycentricCoords = float3(1.0f - attr.barycentrics.x - attr.barycentrics.y, attr.barycentrics.x, attr.barycentrics.y); InstanceData inst = pScene.instances[InstanceID()]; @@ -37,12 +41,103 @@ void closestHit(inout RayPayload hitValue, in BuiltInTriangleIntersectionAttribu FragmentParameter params = FragmentParameter.interpolate(f0, f1, f2, barycentricCoords); MaterialParameter materialParams = params.getMaterialParameter(); + LightingParameter lightingParams = params.getLightingParameter(); + lightingParams.viewDir_WS = -WorldRayDirection(); let brdf = Material.prepare(materialParams); - - hitValue.material.color = float4(brdf.baseColor, 1); - hitValue.material.emissive = float3(0, 0, 0); - hitValue.shading.position = WorldRayOrigin() + RayTCurrent() * WorldRayDirection(); - hitValue.shading.normal = mul(params.getTangentToWorld(), brdf.normal); - hitValue.shading.normalLight = dot(hitValue.shading.normal, WorldRayDirection()) < 0 ? hitValue.shading.normal : -hitValue.shading.normal; + float3 normal_WS = mul(params.getTangentToWorld(), brdf.normal); + float3 normalLight_WS = dot(normal_WS,WorldRayOrigin())<0 ? normal_WS : -normal_WS; + + hitValue.depth++; + float3 localAccRad = float3(0); + float3 rnd = rand01(uint3(vertexIndex0, vertexIndex1, vertexIndex2)); + //float kt = ka + ks; + //float s = -log(rnd.z) / kt; + //float3 xs = r.o + s * r.d; + //if (s < t) { + // float p = kt * rnd.z; + // if (depth > 5) { + // if (rnd.z >= p) break; + // else accmat /= p; + // } + // float3 ldirect = nextEventEstimation(accmat, r.d, xs, -r.d, kt, true, rnd); + // accrad += (fogEmm + ks * ldirect) / kt; + // accmat *= ks / kt; + // rayDesc.Origin = xs; + // rayDesc.Direction = float3( + // cos(2*PI*rnd.x)*sqrt(1-rnd.y*rnd.y), + // sin(2*PI*rnd.x)*sqrt(1-rnd.y*rnd.y), + // rnd.y + // ); + // continue; + //} + + //float p = max(max(brdf.baseColor.x, brdf.baseColor.color.y), brdf.baseColor.color.z); + //if(hitValue.depth > 5) { + // if (rnd.z >= p) return; + // else hitValue.accmat /= p; + //} + + RayDesc rayDesc; + rayDesc.TMax = 10000.0f; + rayDesc.TMin = 0.001f; + + //-- Ideal DIFFUSE reflection + //if(bool(useNEE)) { + // accrad += nextEventEstimation(accmat, r.d, params.x, params.nl, kt, false, rnd); + //} + for(uint i = 0; i < pLightEnv.numDirectionalLights; ++i) { + float3 x = params.position_WS; + float3 l = -pLightEnv.directionalLights[i].direction.xyz; + rayDesc.Origin = x; + rayDesc.Direction = l; + RayPayload payload; + payload.depth = hitValue.depth; + payload.emissive = 1; + payload.anyHit = true; + TraceRay(pRayTracingParams.scene, RAY_FLAG_FORCE_OPAQUE, 0xff, 0, 0, 0, rayDesc, payload); + + // we have missed all geometry, so directional light is affecting us + if(!payload.hit) { + localAccRad += pLightEnv.directionalLights[i].illuminate(lightingParams, brdf); + } + } + //for(uint i = 0; i < pLightEnv.numPointLights; ++i) { + // float3 x = payload.shading.position; + // float3 l = pLightEnv.pointLights[i].position_WS.xyz - payload.shading.position; + // float3 nl = -payload.shading.normal; + // rayDesc.Origin = x; + // rayDesc.Direction = l; + // TraceRay(pRayTracingParams.scene, RAY_FLAG_FORCE_OPAQUE, 0xff, 0, 0, 0, rayDesc, payload); + // + // // hitting only after the light + // if(length(payload.shading.position - x) > length(pLightEnv.pointLights[i].position_WS.xyz - x)) + // { + // float omega = 2 * PI; + // accrad += accmat / PI * max(dot(l,nl),0) * pLightEnv.pointLights[i].colorRange.xyz * omega; + // } + //} + // Indirect Illumination: cosine-weighted importance sampling + if(hitValue.depth < 12) { + float r1 = 2 * PI * rnd.x, r2 = rnd.y, r2s = sqrt(r2); + float3 w = normalLight_WS; + float3 u = normalize((cross(abs(w.x)>0.1 ? float3(0,1,0) : float3(1,0,0), w))); + float3 v = cross(w,u); + rayDesc.Origin = params.position_WS; + rayDesc.Direction = normalize(u*cos(r1)*r2s + v * sin(r1)*r2s + w * sqrt(1 - r2)); + RayPayload payload; + payload.light = float3(0); + payload.emissive = 0; // in the next bounce, consider reflective part only! + payload.depth = hitValue.depth+1; + payload.anyHit = false; + TraceRay(pRayTracingParams.scene, RAY_FLAG_FORCE_OPAQUE, 0xff, 0, 0, 0, rayDesc, payload); + if(payload.hit) { + DirectionalLight dir; + dir.color = float4(payload.light, 0); + dir.direction = float4(-rayDesc.Direction, 0); + localAccRad += dir.illuminate(lightingParams, brdf); + } + } + + hitValue.light += localAccRad; } \ No newline at end of file diff --git a/res/shaders/raytracing/Miss.slang b/res/shaders/raytracing/Miss.slang index 11c5001..51dfcfd 100644 --- a/res/shaders/raytracing/Miss.slang +++ b/res/shaders/raytracing/Miss.slang @@ -3,9 +3,10 @@ import RayTracingData; [shader("miss")] void miss(inout RayPayload p) { - p.shading.position = WorldRayDirection() * 1000.0f; - p.shading.normal = -WorldRayDirection(); - p.shading.normalLight = -WorldRayDirection(); - p.material.color = float4(0, 0, 0, 0); - p.material.emissive = float3(pRayTracingParams.skyBox.Sample(pRayTracingParams.skyBoxSampler, WorldRayDirection()).xyz); +// p.shading.position = WorldRayDirection() * 1000.0f; +// p.shading.normal = -WorldRayDirection(); +// p.shading.normalLight = -WorldRayDirection(); +// p.material.color = float4(0, 0, 0, 0); + p.light = float3(pRayTracingParams.skyBox.Sample(pRayTracingParams.skyBoxSampler, WorldRayDirection()).xyz); + p.hit = false; } \ No newline at end of file diff --git a/res/shaders/raytracing/RayGen.slang b/res/shaders/raytracing/RayGen.slang index c0f13d6..c309c95 100644 --- a/res/shaders/raytracing/RayGen.slang +++ b/res/shaders/raytracing/RayGen.slang @@ -10,7 +10,7 @@ struct Ray const static float S_O = 6.9; const static float f = 0.035; -const static float A = 0.04; +const static float A = 0.0; const static float ka = 0; const static float ks = 0; const static float3 fogEmm = float3(0, 0.01, 0.01); @@ -23,10 +23,6 @@ struct SampleParams layout(push_constant) ConstantBuffer pSamps; -float3 rand01(uint3 x){ // pseudo-random number generator - for (int i=3; i-->0;) x = ((x>>8U)^x.yzx)*1103515245U; - return float3(x)*(1.0/float(0xffffffffU)); -} float3 nextEventEstimation(float3 accmat, float3 w, float3 x, float3 nl, float kt, bool useAtt, float3 rnd) { float3 result = float3(0); @@ -67,6 +63,7 @@ float3 nextEventEstimation(float3 accmat, float3 w, float3 x, float3 nl, float k [shader("raygeneration")] void raygen() { + if(pSamps.pass == pSamps.samplesPerPixel) return; uint2 pix = DispatchRaysIndex().xy; uint2 imgdim = DispatchRaysDimensions().xy; @@ -82,7 +79,6 @@ void raygen() float2 tent = float2(rnd2.x<1 ? sqrt(rnd2.x)-1 : 1-sqrt(2-rnd2.x), rnd2.y<1 ? sqrt(rnd2.y)-1 : 1-sqrt(2-rnd2.y)); float2 s = ((pix + 0.5 * (0.5 + float2((pSamps.pass/2)%2, pSamps.pass%2) + tent)) / float2(imgdim) - 0.5) * sdim; float3 spos = cam.o + cx*s.x + cy*s.y, lc = cam.o + cam.d * 0.035; // sample on 3d sensor plane - float3 accrad=float3(0), accmat=float3(1); // initialize accumulated radiance and bxdf Ray r = Ray(lc, normalize(lc - spos)); // construct ray @@ -107,107 +103,15 @@ void raygen() rayDesc.TMax = 10000.0; const uint maxDepth = 12; - float emissive = 1; RayPayload payload; - for(uint depth = 0; depth < maxDepth; ++depth) { - TraceRay(pRayTracingParams.scene, RAY_FLAG_FORCE_OPAQUE, 0xff, 0, 0, 0, rayDesc, payload); - float3 rnd = rand01(uint3(pix, pSamps.pass*maxDepth + depth)); - //float kt = ka + ks; - //float s = -log(rnd.z) / kt; - //float3 xs = r.o + s * r.d; - //if (s < t) { - // float p = kt * rnd.z; - // if (depth > 5) { - // if (rnd.z >= p) break; - // else accmat /= p; - // } - // float3 ldirect = nextEventEstimation(accmat, r.d, xs, -r.d, kt, true, rnd); - // accrad += (fogEmm + ks * ldirect) / kt; - // accmat *= ks / kt; - // rayDesc.Origin = xs; - // rayDesc.Direction = float3( - // cos(2*PI*rnd.x)*sqrt(1-rnd.y*rnd.y), - // sin(2*PI*rnd.x)*sqrt(1-rnd.y*rnd.y), - // rnd.y - // ); - // continue; - //} - float p = max(max(payload.material.color.x, payload.material.color.y), payload.material.color.z); - if(depth > 5) { - if (rnd.z >= p) break; - else accmat /= p; - } - accrad += accmat * payload.material.emissive * emissive; - accmat *= payload.material.color.xyz; - if (payload.material.color.w == 0) { - break; - } - //-- Ideal DIFFUSE reflection - else if (payload.material.color.w == 1) { - //if(bool(useNEE)) { - // accrad += nextEventEstimation(accmat, r.d, params.x, params.nl, kt, false, rnd); - //} - for(uint i = 0; i < pLightEnv.numDirectionalLights; ++i) { - float3 x = payload.shading.position; - float3 l = -pLightEnv.directionalLights[i].direction.xyz; - float3 nl = l; - rayDesc.Origin = x; - rayDesc.Direction = l; - TraceRay(pRayTracingParams.scene, RAY_FLAG_FORCE_OPAQUE, 0xff, 0, 0, 0, rayDesc, payload); + // initialize accumulated radiance and bxdf + payload.light=float3(0); + payload.emissive = 1; + payload.depth = 1; + payload.anyHit = false; + TraceRay(pRayTracingParams.scene, RAY_FLAG_FORCE_OPAQUE, 0xff, 0, 0, 0, rayDesc, payload); - // we have missed all geometry, so directional light is affecting us - if(payload.material.color.w == 0) { - float omega = 2 * PI; - accrad += accmat / PI * max(dot(l, nl), 0) * pLightEnv.directionalLights[i].color.xyz * omega; - } - } - //for(uint i = 0; i < pLightEnv.numPointLights; ++i) { - // float3 x = payload.shading.position; - // float3 l = pLightEnv.pointLights[i].position_WS.xyz - payload.shading.position; - // float3 nl = -payload.shading.normal; - // rayDesc.Origin = x; - // rayDesc.Direction = l; - // TraceRay(pRayTracingParams.scene, RAY_FLAG_FORCE_OPAQUE, 0xff, 0, 0, 0, rayDesc, payload); -// - // // hitting only after the light - // if(length(payload.shading.position - x) > length(pLightEnv.pointLights[i].position_WS.xyz - x)) - // { - // float omega = 2 * PI; - // accrad += accmat / PI * max(dot(l,nl),0) * pLightEnv.pointLights[i].colorRange.xyz * omega; - // } - //} - // Indirect Illumination: cosine-weighted importance sampling - float r1 = 2 * PI * rnd.x, r2 = rnd.y, r2s = sqrt(r2); - float3 w = payload.shading.normalLight, u = normalize((cross(abs(w.x)>0.1 ? float3(0,1,0) : float3(1,0,0), w))), v = cross(w,u); - rayDesc.Origin = payload.shading.position; - rayDesc.Direction = normalize(u*cos(r1)*r2s + v * sin(r1)*r2s + w * sqrt(1 - r2)); - emissive = 0; // in the next bounce, consider reflective part only! - } - //-- Ideal SPECULAR reflection - else if (payload.material.color.w == 2) { - rayDesc.Origin = payload.shading.position; - rayDesc.Direction = reflect(r.d,payload.shading.normal); - emissive = 1; - } - //-- Ideal dielectric REFRACTION - else if (payload.material.color.w == 3) { - bool into = all(payload.shading.normal==payload.shading.normalLight); - float cos2t, nc=1, nt=1.5, nnt = into ? nc/nt : nt/nc, ddn = dot(r.d,payload.shading.normalLight); - if ((cos2t = 1 - nnt * nnt*(1 - ddn * ddn)) >= 0) { // Fresnel reflection/refraction - float3 tdir = normalize(r.d*nnt - payload.shading.normal * ((into ? 1 : -1)*(ddn*nnt + sqrt(cos2t)))); - float a = nt - nc, b = nt + nc, R0 = a*a/(b*b), c = 1 - (into ? -ddn : dot(tdir,payload.shading.normal)); - float Re = R0 + (1 - R0)*c*c*c*c*c, Tr = 1 - Re, P = 0.25 + 0.5*Re, RP = Re/P, TP = Tr/(1-P); - rayDesc.Origin = payload.shading.position; - rayDesc.Direction = rnd.x < P ? reflect(r.d,payload.shading.normal) : tdir; // pick reflection with probability P - accmat *= rnd.x < P ? RP : TP; // energy compensation - } else { - rayDesc.Origin = payload.shading.position; - rayDesc.Direction = reflect(r.d,payload.shading.normal); // Total internal reflection - } - emissive = 1; - } - } if(pSamps.pass == 0) pRayTracingParams.radianceAccumulator[pix] = float4(0); - pRayTracingParams.radianceAccumulator[pix] += float4(accrad / pSamps.samplesPerPixel, 0); + pRayTracingParams.radianceAccumulator[pix] += float4(payload.light / pSamps.samplesPerPixel, 0); pRayTracingParams.image[pix] = float4(clamp(pRayTracingParams.radianceAccumulator[pix].xyz, 0, 1), 1); } diff --git a/res/shaders/raytracing/RayTracingData.slang b/res/shaders/raytracing/RayTracingData.slang index de7876d..ea7ba9a 100644 --- a/res/shaders/raytracing/RayTracingData.slang +++ b/res/shaders/raytracing/RayTracingData.slang @@ -18,21 +18,16 @@ struct CallablePayload float3 color; }; -struct ShadingParams -{ - float3 position; - float3 normal; - float3 normalLight; -}; - -struct MaterialParams -{ - float4 color; - float3 emissive; -} - struct RayPayload { - ShadingParams shading; - MaterialParams material; -}; \ No newline at end of file + float3 light; + float emissive; + uint depth; + bool hit; + bool anyHit; +}; + +float3 rand01(uint3 x){ // pseudo-random number generator + for (int i=3; i-->0;) x = ((x>>8U)^x.yzx)*1103515245U; + return float3(x)*(1.0/float(0xffffffffU)); +} \ No newline at end of file