Gbuffer rendered by rasterization

README.md

@@ -69,7 +69,7 @@ Scenes specific tweaks are stored in the *SceneSettings* struct.
 
 ## Render passes
 ### GBuffer
-GBuffer rendering is the first pass. It is generated by raytracing. Should normally be done by rasterization to save time but last time i tried it was crashing. See GBuffer.cpp.
+GBuffer rendering is the first pass, it is generated by rasterization. This is faster than tracing primary rays. See GBuffer.cpp.
 
 ### RIS
 Resampled Importance Sampling is performed as described in paper. See RISPass.cpp

Source/Samples/Restir/GBuffer.cpp

@@ -14,77 +14,105 @@ void GBuffer::init(ref<Device> pDevice, ref<Scene> pScene, uint32_t width, uint3
     mHeight = height;
 
     createTextures();
-    compilePrograms();
+    compileProgram();
 }
 
 void GBuffer::createTextures()
 {
     mCurrentPositionWsTexture = mpDevice->createTexture2D(
-        mWidth, mHeight, ResourceFormat::RGBA32Float, 1, 1, nullptr, ResourceBindFlags::ShaderResource | ResourceBindFlags::UnorderedAccess
+        mWidth,
+        mHeight,
+        ResourceFormat::RGBA32Float,
+        1,
+        1,
+        nullptr,
+        ResourceBindFlags::RenderTarget | ResourceBindFlags::ShaderResource | ResourceBindFlags::UnorderedAccess
     );
 
     mPreviousPositionWsTexture = mpDevice->createTexture2D(
-        mWidth, mHeight, ResourceFormat::RGBA32Float, 1, 1, nullptr, ResourceBindFlags::ShaderResource | ResourceBindFlags::UnorderedAccess
+        mWidth,
+        mHeight,
+        ResourceFormat::RGBA32Float,
+        1,
+        1,
+        nullptr,
+        ResourceBindFlags::RenderTarget | ResourceBindFlags::ShaderResource | ResourceBindFlags::UnorderedAccess
     );
 
     mCurrentNormalWsTexture = mpDevice->createTexture2D(
-        mWidth, mHeight, ResourceFormat::RGBA32Float, 1, 1, nullptr, ResourceBindFlags::ShaderResource | ResourceBindFlags::UnorderedAccess
+        mWidth,
+        mHeight,
+        ResourceFormat::RGBA32Float,
+        1,
+        1,
+        nullptr,
+        ResourceBindFlags::RenderTarget | ResourceBindFlags::ShaderResource | ResourceBindFlags::UnorderedAccess
     );
 
     mPreviousNormalWsTexture = mpDevice->createTexture2D(
-        mWidth, mHeight, ResourceFormat::RGBA32Float, 1, 1, nullptr, ResourceBindFlags::ShaderResource | ResourceBindFlags::UnorderedAccess
+        mWidth,
+        mHeight,
+        ResourceFormat::RGBA32Float,
+        1,
+        1,
+        nullptr,
+        ResourceBindFlags::RenderTarget | ResourceBindFlags::ShaderResource | ResourceBindFlags::UnorderedAccess
     );
 
     mAlbedoTexture = mpDevice->createTexture2D(
-        mWidth, mHeight, ResourceFormat::RGBA32Float, 1, 1, nullptr, ResourceBindFlags::ShaderResource | ResourceBindFlags::UnorderedAccess
+        mWidth,
+        mHeight,
+        ResourceFormat::RGBA32Float,
+        1,
+        1,
+        nullptr,
+        ResourceBindFlags::RenderTarget | ResourceBindFlags::ShaderResource | ResourceBindFlags::UnorderedAccess
     );
 
     mSpecularTexture = mpDevice->createTexture2D(
-        mWidth, mHeight, ResourceFormat::RGBA32Float, 1, 1, nullptr, ResourceBindFlags::ShaderResource | ResourceBindFlags::UnorderedAccess
+        mWidth,
+        mHeight,
+        ResourceFormat::RGBA32Float,
+        1,
+        1,
+        nullptr,
+        ResourceBindFlags::RenderTarget | ResourceBindFlags::ShaderResource | ResourceBindFlags::UnorderedAccess
+    );
+
+    mDepthTexture = mpDevice->createTexture2D(
+        mWidth, mHeight, ResourceFormat::D32Float, 1, 1, nullptr, ResourceBindFlags::DepthStencil
     );
 }
 
-void GBuffer::compilePrograms()
+void GBuffer::compileProgram()
 {
     auto shaderModules = mpScene->getShaderModules();
     auto typeConformances = mpScene->getTypeConformances();
-
     auto defines = mpScene->getSceneDefines();
 
-    ProgramDesc rtProgDesc;
-    rtProgDesc.addShaderModules(shaderModules);
-    rtProgDesc.addShaderLibrary("Samples/Restir/GBuffer.slang");
-    rtProgDesc.addTypeConformances(typeConformances);
-    rtProgDesc.setMaxTraceRecursionDepth(1);
-
-    rtProgDesc.setMaxPayloadSize(24);
+    ProgramDesc rasterProgDesc;
+    rasterProgDesc.addShaderModules(shaderModules);
+    rasterProgDesc.addShaderLibrary("Samples/Restir/GBuffer.slang").vsEntry("vsMain").psEntry("psMain");
+    rasterProgDesc.addTypeConformances(typeConformances);
 
-    ref<RtBindingTable> sbt = RtBindingTable::create(1, 1, mpScene->getGeometryCount());
-    sbt->setRayGen(rtProgDesc.addRayGen("rayGen"));
-    sbt->setMiss(0, rtProgDesc.addMiss("primaryMiss"));
-    auto primary = rtProgDesc.addHitGroup("primaryClosestHit", "primaryAnyHit");
-
-    sbt->setHitGroup(0, mpScene->getGeometryIDs(Scene::GeometryType::TriangleMesh), primary);
-
-    mpRaytraceProgram = Program::create(mpDevice, rtProgDesc, defines);
-    mpRtVars = RtProgramVars::create(mpDevice, mpRaytraceProgram, sbt);
+    mpRasterPass = RasterPass::create(mpDevice, rasterProgDesc, defines);
+    mpFbo = Fbo::create(mpDevice);
 }
 
 void GBuffer::render(RenderContext* pRenderContext)
 {
     FALCOR_PROFILE(pRenderContext, "GBuffer::render");
 
-    auto var = mpRtVars->getRootVar();
-
-    var["PerFrameCB"]["viewportDims"] = float2(mWidth, mHeight);
-    var["PerFrameCB"]["sampleIndex"] = mSampleIndex++;
+    mpFbo->attachColorTarget(mCurrentPositionWsTexture, 0u);
+    mpFbo->attachColorTarget(mCurrentNormalWsTexture, 1u);
+    mpFbo->attachColorTarget(mAlbedoTexture, 2u);
+    mpFbo->attachColorTarget(mSpecularTexture, 3u);
+    mpFbo->attachDepthStencilTarget(mDepthTexture);
 
-    var["gPositionWs"] = mCurrentPositionWsTexture;
-    var["gNormalWs"] = mCurrentNormalWsTexture;
-    var["gAlbedo"] = mAlbedoTexture;
-    var["gSpecular"] = mSpecularTexture;
+    pRenderContext->clearFbo(mpFbo.get(), float4(0), 1.f, 0, FboAttachmentType::All);
 
-    mpScene->raytrace(pRenderContext, mpRaytraceProgram.get(), mpRtVars, uint3(mWidth, mHeight, 1));
+    mpRasterPass->getState()->setFbo(mpFbo);
+    mpScene->rasterize(pRenderContext, mpRasterPass->getState().get(), mpRasterPass->getVars().get());
 }
 
 } // namespace Restir

Source/Samples/Restir/GBuffer.h

@@ -1,6 +1,7 @@
 #pragma once
 
 #include "Singleton.h"
+#include "Core/Pass/RasterPass.h"
 
 namespace Restir
 {
@@ -30,7 +31,7 @@ class GBuffer
 
 private:
     void createTextures();
-    void compilePrograms();
+    void compileProgram();
 
     Falcor::ref<Falcor::Device> mpDevice;
     Falcor::ref<Falcor::Scene> mpScene;
@@ -43,12 +44,13 @@ class GBuffer
 
     Falcor::ref<Falcor::Texture> mAlbedoTexture;
     Falcor::ref<Falcor::Texture> mSpecularTexture;
+    Falcor::ref<Falcor::Texture> mDepthTexture;
 
     Falcor::ref<Falcor::Texture> mCurrentNormalWsTexture;
     Falcor::ref<Falcor::Texture> mPreviousNormalWsTexture;
 
-    Falcor::ref<Falcor::Program> mpRaytraceProgram;
-    Falcor::ref<Falcor::RtProgramVars> mpRtVars;
+    Falcor::ref<Falcor::RasterPass> mpRasterPass;
+    Falcor::ref<Falcor::Fbo> mpFbo;
 
     uint32_t mSampleIndex = 0u;
 };

Source/Samples/Restir/GBuffer.slang

@@ -1,87 +1,52 @@
-import Scene.Raytracing;
-import Utils.Sampling.TinyUniformSampleGenerator;
+import Scene.Raster;
 import Rendering.Lights.LightHelpers;
 
-RWTexture2D<float4> gPositionWs;
-RWTexture2D<float4> gNormalWs;
-RWTexture2D<float4> gAlbedo;
-RWTexture2D<float4> gSpecular;
-
-cbuffer PerFrameCB
+VSOut vsMain(VSIn vIn)
 {
-    float2 viewportDims;
-    uint sampleIndex;
-};
+    return defaultVS(vIn);
+}
 
-struct PrimaryRayData
+struct GBufferPSOut
 {
-    bool dummy;
+    float4 positionWs : SV_TARGET0;
+    float4 normalWs : SV_TARGET1;
+    float4 albedo : SV_TARGET2;
+    float4 specular : SV_TARGET3;
 };
 
-[shader("miss")]
-void primaryMiss(inout PrimaryRayData hitData)
+GBufferPSOut psMain(VSOut vsOut, uint triangleIndex : SV_PrimitiveID) : SV_TARGET
 {
-    uint2 launchIndex = DispatchRaysIndex().xy;
-    gPositionWs[launchIndex].w = 0.0f;
-}
+    GBufferPSOut psOut = {};
 
-[shader("closesthit")]
-void primaryClosestHit(inout PrimaryRayData hitData, BuiltInTriangleIntersectionAttributes attribs)
-{
-    // Get the hit-point data.
-    float3 rayDirW = WorldRayDirection();
-    float hitT = RayTCurrent();
-    uint triangleIndex = PrimitiveIndex();
+    const float3 faceNormal = gScene.getFaceNormalW(vsOut.instanceID, triangleIndex);
+    const VertexData v = prepareVertexData(vsOut, faceNormal);
+    const let lod = ImplicitLodTextureSampler();
 
-    // Prepare the shading data.
-    const GeometryInstanceID instanceID = getGeometryInstanceID();
-    VertexData v = getVertexData(instanceID, triangleIndex, attribs);
-    uint materialID = gScene.getMaterialID(instanceID);
-    ShadingData sd = gScene.materials.prepareShadingData(v, materialID, -rayDirW);
+    const float3 viewDir = normalize(gScene.camera.getPosition() - v.posW);
+    const ShadingData sd = prepareShadingData(vsOut, triangleIndex, viewDir);
 
-    // Create material instance and query its properties.
-    let lod = ExplicitLodTextureSampler(0.f);
     let mi = gScene.materials.getMaterialInstance(sd, lod);
     let bsdfProperties = mi.getProperties(sd);
 
-    // The launch index.
-    const uint2 launchIndex = DispatchRaysIndex().xy;
-
     // Write the ws position.
     {
-        gPositionWs[launchIndex] = float4(sd.posW, 1.f);
+        psOut.positionWs = float4(sd.posW, 1.f);
     }
-    // Write the ws normal.
+
+    // Write the ws normal and hit distance.
     {
-        gNormalWs[launchIndex] = float4(sd.faceN, hitT);
+        psOut.normalWs = float4(sd.faceN, length(gScene.camera.getPosition() - sd.posW));
     }
 
-    // Write the albedo.
+    // Write the albedo and material id.
     {
-        gAlbedo[launchIndex] = float4(bsdfProperties.diffuseReflectionAlbedo, materialID);
+        psOut.albedo = float4(bsdfProperties.diffuseReflectionAlbedo, vsOut.materialID);
     }
 
-    // Write the specular.
+    // Write the specular and roughness.
     {
-        gSpecular[launchIndex] = float4(bsdfProperties.specularReflectionAlbedo, bsdfProperties.roughness);
+        psOut.specular = float4(bsdfProperties.specularReflectionAlbedo, bsdfProperties.roughness);
     }
-}
 
-[shader("anyhit")]
-void primaryAnyHit(inout PrimaryRayData rayData, BuiltInTriangleIntersectionAttributes attribs)
-{
+    return psOut;
 }
-
-[shader("raygeneration")]
-void rayGen()
-{
-    uint3 launchIndex = DispatchRaysIndex();
-    if (any(launchIndex.xy > (uint2)viewportDims))
-        return;
-
-    const RayDesc ray = gScene.camera.computeRayPinhole(launchIndex.xy, viewportDims).toRayDesc();
-
-    PrimaryRayData hitData;
-    TraceRay(gScene.rtAccel, 0 /*rayFlags*/, 0xFF, 0 /* ray index*/, rayTypeCount, 0, ray, hitData);
-}
-