import Common; import MaterialParameter; import LightEnv; import Scene; import RayTracingData; import VertexData; import Material; import StaticMeshVertexData; import MATERIAL_FILE_NAME; // simplification: all BLAS only have 1 geometry /*vec3 nextEventEstimation(vec3 accmat, vec3 w, vec3 x, vec3 nl, float kt, bool useAtt, vec3 rnd) { uint triId = 0; uint sphereId = 0; ShadingParams paramsls; Material matls; vec3 result = vec3(0); // Direct Illumination: Next Event Estimation over any present lights for (int i = spheres.length(); i-->0;) { Sphere ls = spheres[i]; if (all(equal(ls.e, vec3(0)))) continue; // skip non-emissive spheres vec3 xc = ls.geo.xyz - x; vec3 sw = normalize(xc), su = normalize(cross((abs(sw.x)>.1 ? vec3(0,1,0) : vec3(1,0,0)), sw)), sv = cross(sw,su); float cos_a_max = sqrt(float(1 - ls.geo.w*ls.geo.w / dot(xc,xc))); float cos_a = 1 - rnd.x + rnd.x*cos_a_max, sin_a = sqrt(1 - cos_a*cos_a); float phi = 2 * pi * rnd.y; vec3 l = normalize(su*cos(phi)*sin_a + sv*sin(phi)*sin_a + sw*cos_a); // sampled direction towards light if (intersect(Ray(x,l), matls, paramsls, sphereId, triId) && sphereId == i) { // test if shadow ray hits this light source float omega = 2 * pi * (1-cos_a_max); if(useAtt) { float tau = exp(-kt * length(x - paramsls.x)); result += max(dot(l,nl),0) * ls.e * omega * tau; } else { result += accmat / pi * max(dot(l,nl),0) * ls.e * omega; // brdf term obj.c.xyz already in accmat, 1/pi for brdf } } } for(int i = meshLights.length(); i-->0;) { MeshDescriptor mesh = meshes[meshLights[i]]; for(int j = 0; j < mesh.numIndices; j+=3) { vec3 A = vec3(vertices[mesh.vertexOffset + indices[mesh.indexOffset + j + 0]]); vec3 B = vec3(vertices[mesh.vertexOffset + indices[mesh.indexOffset + j + 1]]); vec3 C = vec3(vertices[mesh.vertexOffset + indices[mesh.indexOffset + j + 2]]); float b1 = 1 - sqrt(rnd.x); float b2 = (1 - rnd.y) * sqrt(rnd.x); float b3 = rnd.y * sqrt(rnd.x); vec3 P = A * b1 + B * b2 + C * b3; vec3 omega = P - x; vec3 l = normalize(omega); float v = 0.f; if(intersect(Ray(x,l), matls, paramsls, sphereId, triId) && triId == j) { v = 1.0f; } vec3 e1 = C - A; vec3 e2 = B - A; float area = length(cross(e1, e2)) / 2; float rayLen = length(omega); float cosTheta = dot(nl, l); float cosThetaDash = dot(paramsls.n, -l); float factor = area * (cosThetaDash / (rayLen * rayLen)); if(useAtt) { float tau = phase(w, l) * exp(-kt * length(x - paramsls.x)); result += tau * matls.e * max(cosTheta, 0) * factor; } else { result += accmat * (matls.e * max(cosTheta, 0) * factor) / pi; } } } return result; } */ const static float ka = 0; const static float ks = 0; const static float3 fogEmm = float3(0, 0.01, 0.01); const static float eps = 1e-5; [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()]; MeshData m = pScene.meshData[InstanceID()]; // offset into the index buffer uint indexOffset = m.indicesRange.offset; // added to indices to reference correct part of global mesh pool uint vertexOffset = pScene.meshletInfos[m.meshletRange.offset].indicesOffset; uint vertexIndex0 = vertexOffset + pRayTracingParams.indexBuffer[indexOffset + 3 * PrimitiveIndex() + 0]; uint vertexIndex1 = vertexOffset + pRayTracingParams.indexBuffer[indexOffset + 3 * PrimitiveIndex() + 1]; uint vertexIndex2 = vertexOffset + pRayTracingParams.indexBuffer[indexOffset + 3 * PrimitiveIndex() + 2]; VertexAttributes attr0 = pVertexData.getAttributes(vertexIndex0); VertexAttributes attr1 = pVertexData.getAttributes(vertexIndex1); VertexAttributes attr2 = pVertexData.getAttributes(vertexIndex2); FragmentParameter f0 = attr0.getParameter(inst.transformMatrix, inst.inverseTransformMatrix); FragmentParameter f1 = attr1.getParameter(inst.transformMatrix, inst.inverseTransformMatrix); FragmentParameter f2 = attr2.getParameter(inst.transformMatrix, inst.inverseTransformMatrix); FragmentParameter params = FragmentParameter.interpolate(f0, f1, f2, barycentricCoords); hitValue.params = params.getLightingParameter(); hitValue.materialParams = params.getMaterialParameter(); LightingParameter lightingParams = hitValue.params; lightingParams.viewDir_WS = -WorldRayDirection(); let brdf = Material.prepare(hitValue.materialParams); float3 normal_WS = brdf.getNormal(); float3 normalLight_WS = dot(normal_WS, WorldRayDirection()) < 0 ? normal_WS : -normal_WS; float3 intersection_WS = lightingParams.position_WS; hitValue.depth++; float3 rnd = rand01(hitValue.rndSeed); // float kt = ka + ks; // float s = -log(rnd.z) / kt; // if (s < RayTCurrent()) { // float3 xs = WorldRayOrigin() + s * WorldRayDirection(); // float p = kt * rnd.z; // if (hitValue.depth > 5) { // if (rnd.z >= p) return; // else brdf.baseColor /= p; // } // float3 ldirect = nextEventEstimation(brdf.baseColor, WorldRayDirection(), xs, -WorldRayDirection(), kt, true, rnd); // hitValue.light += (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 // ); // TraceRay(scene, 0, 0xff, 0, 0, rayDesc); // } float p = max(max(brdf.getBaseColor().x, brdf.getBaseColor().y), brdf.getBaseColor().z); if (hitValue.depth > 5) { if (rnd.z >= p) return; } hitValue.light += brdf.getEmissive() * hitValue.emissive + brdf.evaluateAmbient(lightingParams.viewDir_WS); //-- Ideal DIFFUSE reflection // if(bool(useNEE)) { // accrad += nextEventEstimation(accmat, r.d, params.x, params.nl, kt, false, rnd); //} // Only trace shadow rays for direct lighting at shallow depths if (hitValue.depth <= 3) { for (uint i = 0; i < pLightEnv.numDirectionalLights; ++i) { float3 x = intersection_WS; float3 l = -pLightEnv.directionalLights[i].direction.xyz; RayDesc rayDesc; rayDesc.TMax = 10000.0f; rayDesc.TMin = eps; rayDesc.Origin = x; rayDesc.Direction = l; RayPayload payload; payload.depth = hitValue.depth; payload.emissive = 1; payload.anyHit = true; payload.hit = false; payload.rndSeed = hitValue.rndSeed; TraceRay(pRayTracingParams.scene, RAY_FLAG_CULL_BACK_FACING_TRIANGLES | RAY_FLAG_ACCEPT_FIRST_HIT_AND_END_SEARCH, 0xff, 0, 0, 0, rayDesc, payload); // we have missed all geometry, so directional light is affecting us if (!payload.hit) { hitValue.light += pLightEnv.directionalLights[i].illuminate(lightingParams, brdf); } } for (uint i = 0; i < pLightEnv.numPointLights; ++i) { RayPayload payload; payload.rndSeed = hitValue.rndSeed; float3 x = intersection_WS; float3 l = pLightEnv.pointLights[i].position_WS.xyz - intersection_WS; if (length(l) > pLightEnv.pointLights[i].colorRange.w) { continue; } RayDesc rayDesc; rayDesc.TMax = 1.0f; rayDesc.TMin = eps; rayDesc.Origin = x; rayDesc.Direction = l; TraceRay(pRayTracingParams.scene, RAY_FLAG_CULL_BACK_FACING_TRIANGLES | RAY_FLAG_ACCEPT_FIRST_HIT_AND_END_SEARCH, 0xff, 0, 0, 0, rayDesc, payload); // hitting only after the light if (!payload.hit) { hitValue.light += pLightEnv.pointLights[i].illuminate(lightingParams, brdf); } } } // end depth <= 2 direct lighting guard // Indirect Illumination: probabilistic diffuse/specular importance sampling if (hitValue.depth < 3) { float3 V = -WorldRayDirection(); float3 N = normalLight_WS; float rough = brdf.getRoughness(); float met = brdf.getMetallic(); float3 F0 = lerp(float3(0.04), brdf.getBaseColor(), met); float NdotV = max(dot(N, V), 0.001); float3 F = F0 + (1 - F0) * pow(1 - NdotV, 5.0); float specProb = clamp((F.x + F.y + F.z) / 3.0, 0.1, 0.9); RayDesc rayDesc; rayDesc.TMax = 10000.0f; rayDesc.TMin = eps; rayDesc.Origin = intersection_WS; float3 bounceWeight = float3(0); bool validBounce = true; if (rnd.z < specProb) { // GGX importance sampling for specular reflection float a = max(rough * rough, 0.001); float a2 = a * a; float phi = 2.0 * PI * rnd.x; float cosTheta = sqrt((1.0 - rnd.y) / (1.0 + (a2 - 1.0) * rnd.y)); float sinTheta = sqrt(1.0 - cosTheta * cosTheta); float3 u = normalize(cross(abs(N.x) > 0.1 ? float3(0, 1, 0) : float3(1, 0, 0), N)); float3 v = cross(N, u); float3 H = normalize(u * cos(phi) * sinTheta + v * sin(phi) * sinTheta + N * cosTheta); float3 L = reflect(-V, H); rayDesc.Direction = L; float NdotL = dot(N, L); float NdotH = max(dot(N, H), 0.0); float VdotH = max(dot(V, H), 0.0); if (NdotL <= 0) { validBounce = false; } else { // Smith G term float k = (rough + 1); k = (k * k) / 8; float G = (NdotV / (NdotV * (1 - k) + k)) * (NdotL / (NdotL * (1 - k) + k)); // Fresnel at half-vector float3 Fh = F0 + (max(float3(1.0 - rough), F0) - F0) * pow(clamp(1 - VdotH, 0, 1), 5.0); // Monte Carlo weight: F * G * VdotH / (NdotH * NdotV * specProb) bounceWeight = Fh * G * VdotH / (NdotH * NdotV * specProb + 0.0001); } } else { // Cosine-weighted importance sampling for diffuse float r1 = 2 * PI * rnd.x, r2 = rnd.y, r2s = sqrt(r2); float3 w = N; float3 u = normalize(cross(abs(w.x) > 0.1 ? float3(0, 1, 0) : float3(1, 0, 0), w)); float3 v = cross(w, u); rayDesc.Direction = normalize(u * cos(r1) * r2s + v * sin(r1) * r2s + w * sqrt(1 - r2)); // Diffuse weight: kd * baseColor / (1 - specProb) float3 kd = (1 - F) * (1 - met); bounceWeight = kd * brdf.getBaseColor() / (1 - specProb); } if (validBounce) { RayPayload payload; payload.light = float3(0); payload.hit = false; payload.emissive = 0; payload.depth = hitValue.depth; payload.anyHit = false; payload.rndSeed = hitValue.rndSeed + 1; TraceRay(pRayTracingParams.scene, RAY_FLAG_CULL_BACK_FACING_TRIANGLES, 0xff, 0, 0, 0, rayDesc, payload); hitValue.light += bounceWeight * payload.light; } } // hitValue.light /= p; }