Compute and visualize Diffuse Irradiance.

samples/00_util/gpu_resource_manager.cpp

@@ -22,7 +22,7 @@ TextureManager::Init(const u32 maxCapacity)
 TextureHandle
 TextureManager::Commit(Texture *texture)
 {
-    ERROR_IF(!texture || !texture->IsValid() || !texture->IsOwned(), "Texture must be valid and owned for commital")
+    ERROR_IF(!texture || !texture->IsValid(), "Texture must be valid for commital")
     THEN_ABORT(-1);
 
     if (m_FreeHead != GpuResourceHandle::INVALID_HANDLE)

samples/03_model_render/CMakeLists.txt

@@ -19,9 +19,10 @@ add_executable(model_render model_render.cpp
 
 add_shader(model_render shader/model.vs.hlsl)
 add_shader(model_render shader/model.ps.hlsl)
-add_shader(model_render shader/eqrectToCube.cs.hlsl)
+add_shader(model_render shader/eqrect_to_cube.cs.hlsl)
 add_shader(model_render shader/background.vs.hlsl)
 add_shader(model_render shader/background.ps.hlsl)
+add_shader(model_render shader/diffuse_irradiance.cs.hlsl)
 
 target_link_libraries(model_render PRIVATE aster_core)
 target_link_libraries(model_render PRIVATE util_helper)

samples/03_model_render/ibl_helpers.cpp

@@ -5,27 +5,41 @@
 
 #include "ibl_helpers.h"
 
+#include "EASTL/fixed_vector.h"
+#include "EASTL/tuple.h"
 #include "asset_loader.h"
 #include "device.h"
 #include "gpu_resource_manager.h"
 #include "helpers.h"
 #include "image.h"
 #include "pipeline_utils.h"
-#include "EASTL/tuple.h"
 
-constexpr cstr EQUIRECT_TO_CUBE_SHADER_FILE = "shader/eqrectToCube.cs.hlsl.spv";
+constexpr cstr EQUIRECT_TO_CUBE_SHADER_FILE = "shader/eqrect_to_cube.cs.hlsl.spv";
+constexpr cstr DIFFUSE_IRRADIANCE_SHADER_FILE = "shader/diffuse_irradiance.cs.hlsl.spv";
 
-TextureHandle
+eastl::tuple<TextureHandle, TextureHandle>
 CreateCubeFromHdrEnv(AssetLoader *assetLoader, vk::Queue computeQueue, const u32 cubeSide, TextureHandle hdrEnv,
                      const cstr name)
 {
     GpuResourceManager *resMan = assetLoader->m_ResourceManager;
     const Device *pDevice = resMan->m_Device;
 
-    StorageTextureCube cubeMap;
+    StackString<64> skyboxName = "Skybox: ";
-    cubeMap.Init(pDevice, cubeSide, vk::Format::eR16G16B16A16Sfloat, true, false, name ? name : "Env CubeMap");
+    StackString<64> diffuseIrradianceName = "DiffIrr: ";
-    StorageTextureHandle envStagingHandle = resMan->CommitStorageTexture(&cubeMap);
+    skyboxName += name ? name : "";
+    diffuseIrradianceName += name ? name : "";
 
+    StorageTextureCube skybox;
+    skybox.Init(pDevice, cubeSide, vk::Format::eR16G16B16A16Sfloat, true, false, skyboxName.c_str());
+    TextureHandle skyboxHandle = resMan->CommitTexture(&skybox);
+    StorageTextureHandle skyboxStorageHandle = resMan->CommitStorageTexture(&skybox);
+
+    StorageTextureCube diffuseIrradiance;
+    diffuseIrradiance.Init(pDevice, 64, vk::Format::eR16G16B16A16Sfloat, true, false, diffuseIrradianceName.c_str());
+    TextureHandle diffuseIrradianceHandle = resMan->CommitTexture(&diffuseIrradiance);
+    StorageTextureHandle diffuseIrradianceStorageHandle = resMan->CommitStorageTexture(&diffuseIrradiance);
+
+#pragma region Dependencies and Copies
     vk::ImageSubresourceRange cubeSubresRange = {
         .aspectMask = vk::ImageAspectFlagBits::eColor,
         .baseMipLevel = 0,
@@ -34,7 +48,7 @@ CreateCubeFromHdrEnv(AssetLoader *assetLoader, vk::Queue computeQueue, const u32
         .layerCount = 6,
     };
 
-    vk::ImageMemoryBarrier2 readyToWriteBarrier = {
+    vk::ImageMemoryBarrier2 readyToWriteBarrierTemplate = {
         .srcStageMask = vk::PipelineStageFlagBits2::eTopOfPipe,
         .srcAccessMask = vk::AccessFlagBits2::eNone,
         .dstStageMask = vk::PipelineStageFlagBits2::eComputeShader,
@@ -43,50 +57,73 @@ CreateCubeFromHdrEnv(AssetLoader *assetLoader, vk::Queue computeQueue, const u32
         .newLayout = vk::ImageLayout::eGeneral,
         .srcQueueFamilyIndex = VK_QUEUE_FAMILY_IGNORED,
         .dstQueueFamilyIndex = VK_QUEUE_FAMILY_IGNORED,
-        .image = cubeMap.m_Image,
         .subresourceRange = cubeSubresRange,
     };
+    eastl::fixed_vector<vk::ImageMemoryBarrier2, 3> readyToWriteBarriers(2, readyToWriteBarrierTemplate);
+    readyToWriteBarriers[0].image = skybox.m_Image;
+    readyToWriteBarriers[1].image = diffuseIrradiance.m_Image;
+
     vk::DependencyInfo readyToWriteDependency = {
-        .imageMemoryBarrierCount = 1,
+        .imageMemoryBarrierCount = Cast<u32>(readyToWriteBarriers.size()),
-        .pImageMemoryBarriers = &readyToWriteBarrier,
+        .pImageMemoryBarriers = readyToWriteBarriers.data(),
     };
-    vk::ImageMemoryBarrier2 cubemapToRead = {
+
+    vk::ImageMemoryBarrier2 skyboxWriteToReadBarrier = {
         .srcStageMask = vk::PipelineStageFlagBits2::eComputeShader,
         .srcAccessMask = vk::AccessFlagBits2::eShaderStorageWrite,
+        .dstStageMask = vk::PipelineStageFlagBits2::eComputeShader,
+        .dstAccessMask = vk::AccessFlagBits2::eShaderStorageRead,
+        .oldLayout = vk::ImageLayout::eGeneral,
+        .newLayout = vk::ImageLayout::eGeneral,
+        .srcQueueFamilyIndex = VK_QUEUE_FAMILY_IGNORED,
+        .dstQueueFamilyIndex = VK_QUEUE_FAMILY_IGNORED,
+        .image = skybox.m_Image,
+        .subresourceRange = cubeSubresRange,
+    };
+
+    vk::DependencyInfo skyboxWriteToReadDependency = {
+        .imageMemoryBarrierCount = 1,
+        .pImageMemoryBarriers = &skyboxWriteToReadBarrier,
+    };
+
+    vk::ImageMemoryBarrier2 skyboxToSampleBarrier = {
+        .srcStageMask = vk::PipelineStageFlagBits2::eComputeShader,
+        .srcAccessMask = vk::AccessFlagBits2::eShaderStorageWrite | vk::AccessFlagBits2::eShaderStorageRead,
         .dstStageMask = vk::PipelineStageFlagBits2::eFragmentShader,
         .dstAccessMask = vk::AccessFlagBits2::eShaderSampledRead,
         .oldLayout = vk::ImageLayout::eGeneral,
         .newLayout = vk::ImageLayout::eShaderReadOnlyOptimal,
         .srcQueueFamilyIndex = VK_QUEUE_FAMILY_IGNORED,
         .dstQueueFamilyIndex = VK_QUEUE_FAMILY_IGNORED,
-        .image = cubeMap.m_Image,
+        .image = skybox.m_Image,
         .subresourceRange = cubeSubresRange,
     };
-    vk::DependencyInfo cubemapToReadDependency = {
+    vk::DependencyInfo skyboxToSampleDependency = {
         .imageMemoryBarrierCount = 1,
-        .pImageMemoryBarriers = &cubemapToRead,
+        .pImageMemoryBarriers = &skyboxToSampleBarrier,
     };
 
-    struct WorkloadPushConstants
+#pragma endregion
+
+    struct SkyboxPushConstants
     {
         TextureHandle m_HdrEnvHandle;
         StorageTextureHandle m_OutputTexture;
         u32 m_CubeSide;
     };
+    struct DiffuseIrradiancePushConstants
+    {
+        TextureHandle m_SkyboxHandle;
+        StorageTextureHandle m_OutputTexture;
+        u32 m_CubeSide;
+    };
 
 #pragma region Pipeline Creation etc
-    const auto shaderModule = CreateShader(pDevice, EQUIRECT_TO_CUBE_SHADER_FILE);
-
-    const vk::PipelineShaderStageCreateInfo shaderStageCreateInfo = {
-        .stage = vk::ShaderStageFlagBits::eCompute,
-        .module = shaderModule,
-        .pName = "main",
-    };
 
     vk::PushConstantRange pcr = {
         .stageFlags = vk::ShaderStageFlagBits::eCompute,
         .offset = 0,
-        .size = sizeof(WorkloadPushConstants),
+        .size = eastl::max(sizeof(SkyboxPushConstants), sizeof(DiffuseIrradiancePushConstants)),
     };
 
     vk::PipelineLayout pipelineLayout;
@@ -98,21 +135,55 @@ CreateCubeFromHdrEnv(AssetLoader *assetLoader, vk::Queue computeQueue, const u32
     };
     AbortIfFailed(pDevice->m_Device.createPipelineLayout(&layoutCreateInfo, nullptr, &pipelineLayout));
 
-    const vk::ComputePipelineCreateInfo computePipelineCreateInfo = {
+    const auto eqRectToCubeShader = CreateShader(pDevice, EQUIRECT_TO_CUBE_SHADER_FILE);
-        .stage = shaderStageCreateInfo,
+    const auto diffuseRadianceShader = CreateShader(pDevice, DIFFUSE_IRRADIANCE_SHADER_FILE);
+    eastl::array computePipelineCreateInfo = {
+        vk::ComputePipelineCreateInfo{
+            .stage =
+                {
+                    .stage = vk::ShaderStageFlagBits::eCompute,
+                    .module = eqRectToCubeShader,
+                    .pName = "main",
+                },
             .layout = pipelineLayout,
+        },
+        vk::ComputePipelineCreateInfo{
+            .stage =
+                {
+                    .stage = vk::ShaderStageFlagBits::eCompute,
+                    .module = diffuseRadianceShader,
+                    .pName = "main",
+                },
+            .layout = pipelineLayout,
+        },
     };
 
-    vk::Pipeline pipeline;
+    eastl::array<vk::Pipeline, 2> pipelines;
-    AbortIfFailed(pDevice->m_Device.createComputePipelines(pDevice->m_PipelineCache, 1, &computePipelineCreateInfo,
+    static_assert(pipelines.size() == computePipelineCreateInfo.size());
-                                                           nullptr, &pipeline));
+    AbortIfFailed(pDevice->m_Device.createComputePipelines(pDevice->m_PipelineCache, computePipelineCreateInfo.size(),
+                                                           computePipelineCreateInfo.data(), nullptr,
+                                                           pipelines.data()));
 
-    pDevice->m_Device.destroy(shaderModule, nullptr);
+    vk::Pipeline eqRectToCubePipeline = pipelines[0];
+    vk::Pipeline diffuseIrradiancePipeline = pipelines[1];
+
+    for (auto &createInfos : computePipelineCreateInfo)
+    {
+        pDevice->m_Device.destroy(createInfos.stage.module, nullptr);
+    }
 
 #pragma endregion
 
-    WorkloadPushConstants pushConstants = {
+    SkyboxPushConstants skyboxPushConstant = {
-        .m_HdrEnvHandle = hdrEnv, .m_OutputTexture = envStagingHandle, .m_CubeSide = cubeSide};
+        .m_HdrEnvHandle = hdrEnv,
+        .m_OutputTexture = skyboxStorageHandle,
+        .m_CubeSide = cubeSide,
+    };
+    DiffuseIrradiancePushConstants diffuseIrradiancePushConstants = {
+        .m_SkyboxHandle = skyboxHandle,
+        .m_OutputTexture = diffuseIrradianceStorageHandle,
+        .m_CubeSide = diffuseIrradiance.m_Extent.width,
+    };
 
     resMan->Update();
 
@@ -133,11 +204,19 @@ CreateCubeFromHdrEnv(AssetLoader *assetLoader, vk::Queue computeQueue, const u32
     cmd.pipelineBarrier2(&readyToWriteDependency);
 
     cmd.bindDescriptorSets(vk::PipelineBindPoint::eCompute, pipelineLayout, 0, 1, &resMan->m_DescriptorSet, 0, nullptr);
-    cmd.bindPipeline(vk::PipelineBindPoint::eCompute, pipeline);
+    cmd.bindPipeline(vk::PipelineBindPoint::eCompute, eqRectToCubePipeline);
-    cmd.pushConstants(pipelineLayout, vk::ShaderStageFlagBits::eCompute, 0, sizeof pushConstants, &pushConstants);
+    cmd.pushConstants(pipelineLayout, vk::ShaderStageFlagBits::eCompute, 0, sizeof skyboxPushConstant,
+                      &skyboxPushConstant);
     cmd.dispatch(cubeSide / 16, cubeSide / 16, 6);
 
-    cmd.pipelineBarrier2(&cubemapToReadDependency);
+    cmd.pipelineBarrier2(&skyboxWriteToReadDependency);
+
+    cmd.pushConstants(pipelineLayout, vk::ShaderStageFlagBits::eCompute, 0, sizeof skyboxPushConstant,
+                      &diffuseIrradiancePushConstants);
+    cmd.bindPipeline(vk::PipelineBindPoint::eCompute, diffuseIrradiancePipeline);
+    cmd.dispatch(cubeSide / 16, cubeSide / 16, 6);
+
+    cmd.pipelineBarrier2(&skyboxToSampleDependency);
 
 #if !defined(NDEBUG)
     cmd.endDebugUtilsLabelEXT();
@@ -161,10 +240,14 @@ CreateCubeFromHdrEnv(AssetLoader *assetLoader, vk::Queue computeQueue, const u32
 
     AbortIfFailed(pDevice->m_Device.resetCommandPool(assetLoader->m_CommandPool, {}));
 
-    cubeMap = {};
+    skybox = {};
-    resMan->Release(&cubeMap, envStagingHandle);
+    resMan->Release(skyboxStorageHandle);
+    resMan->Release(diffuseIrradianceStorageHandle);
+    for (auto &pipeline : pipelines)
+    {
         pDevice->m_Device.destroy(pipeline, nullptr);
+    }
     pDevice->m_Device.destroy(pipelineLayout, nullptr);
 
-    return resMan->CommitTexture(&cubeMap);
+    return {skyboxHandle, diffuseIrradianceHandle};
 }

samples/03_model_render/ibl_helpers.h

@@ -8,10 +8,13 @@
 #include "global.h"
 #include "gpu_resource_manager.h"
 
+#include <EASTL/tuple.h>
+
 struct Pipeline;
 struct Texture;
 struct TextureCube;
 struct AssetLoader;
 
-TextureHandle CreateCubeFromHdrEnv(AssetLoader *assetLoader, vk::Queue computeQueue, u32 cubeSide, TextureHandle hdrEnv,
+eastl::tuple<TextureHandle, TextureHandle>
+CreateCubeFromHdrEnv(AssetLoader *assetLoader, vk::Queue computeQueue, u32 cubeSide, TextureHandle hdrEnv,
                                    cstr name = nullptr);

samples/03_model_render/model_render.cpp

@@ -18,10 +18,10 @@
 #include "helpers.h"
 #include "light_manager.h"
 
+#include "asset_loader.h"
 #include "gpu_resource_manager.h"
 #include "gui.h"
 #include "ibl_helpers.h"
-#include "asset_loader.h"
 #include "pipeline_utils.h"
 
 #include <EASTL/array.h>
@@ -180,7 +180,7 @@ main(int, char **)
     assetLoader.LoadHdrImage(&environment, BACKDROP_FILE);
     auto envHandle = resourceManager.CommitTexture(&environment);
 
-    TextureHandle texCube = CreateCubeFromHdrEnv(&assetLoader, graphicsQueue, 1024, envHandle, "Cube Env");
+    auto [texCube, diffuseIrr] = CreateCubeFromHdrEnv(&assetLoader, graphicsQueue, 1024, envHandle, "Cube Env");
 
     resourceManager.Release(envHandle);
 
@@ -371,6 +371,7 @@ main(int, char **)
               queueAllocation.m_Family, graphicsQueue);
     bool rotating = false;
     bool lockToScreen = true;
+    bool showDiffuse = false;
     i32 height = Cast<i32>(internalResolution.height);
     f32 camPitch = glm::degrees(cameraController.m_Pitch);
     f32 camYaw = glm::degrees(cameraController.m_Yaw);
@@ -445,6 +446,7 @@ main(int, char **)
         {
             cameraController.SetPosition(camPosition);
         }
+        gui::Checkbox("Show DiffIrr", &showDiffuse);
         gui::Checkbox("Rotate", &rotating);
         gui::PopItemWidth();
         if (gui::Button("Exit"))
@@ -546,8 +548,18 @@ main(int, char **)
         cmd.pushConstants(pipeline.m_Layout, vk::ShaderStageFlagBits::eAll, pcbOffset, sizeof model.m_Handles,
                           &model.m_Handles);
         pcbOffset += sizeof model.m_Handles;
+        if (showDiffuse)
+        {
+            cmd.pushConstants(pipeline.m_Layout, vk::ShaderStageFlagBits::eAll, pcbOffset, sizeof diffuseIrr,
+                              &diffuseIrr);
+            pcbOffset += sizeof diffuseIrr;
+        }
+        else
+        {
             cmd.pushConstants(pipeline.m_Layout, vk::ShaderStageFlagBits::eAll, pcbOffset, sizeof texCube, &texCube);
             pcbOffset += sizeof texCube;
+        }
+        static_assert(sizeof texCube == sizeof diffuseIrr);
         cmd.pushConstants(pipeline.m_Layout, vk::ShaderStageFlagBits::eAll, pcbOffset, sizeof lightManager.m_MetaInfo,
                           &lightManager.m_MetaInfo);
         pcbOffset += sizeof lightManager.m_MetaInfo;
@@ -626,6 +638,7 @@ main(int, char **)
     AbortIfFailed(device.m_Device.waitIdle());
 
     resourceManager.Release(texCube);
+    resourceManager.Release(diffuseIrr);
 
     pipelineCacheData = device.DumpPipelineCache();
     ERROR_IF(!WriteFileBytes(PIPELINE_CACHE_FILE, pipelineCacheData), "Pipeline Cache incorrectly written");

samples/03_model_render/shader/bindless_structs.hlsli

@@ -48,7 +48,9 @@ struct DirectionalLight
 
 #define INVALID_HANDLE 0xFFFFFFFF
 
+static const float HALF_PI = 1.57079633f;
 static const float PI = 3.14159265f;
+static const float TAU = 6.28318530f;
 
 [[vk::binding(0, 0)]] StructuredBuffer<float4> VertexBuffer[];
 [[vk::binding(0, 0)]] StructuredBuffer<VertexData> VertexDataBuffer[];

samples/03_model_render/shader/diffuse_irradiance.cs.hlsl

@@ -0,0 +1,51 @@
+#include "ibl_common.hlsli"
+
+struct Block
+{
+    uint SkyboxHandle;
+    uint OutputTextureHandle;
+    int CubeSide;
+};
+
+[[vk::push_constant]]
+Block pcb;
+
+/*
+| Axis | Layer | Up |
+|:----:|:-----:|:--:|
+|  +x  |   0   | -y |
+|  -x  |   1   | -y |
+|  +y  |   2   | +z |
+|  -y  |   3   | -z |
+|  -z  |   4   | -y |
+|  +z  |   5   | -y |
+*/
+
+[numthreads(16, 16, 1)]
+void main(uint3 GlobalInvocationID : SV_DispatchThreadID)
+{
+    float3 Forward, Up, Right;
+    
+    Forward = GetLocalDir(pcb.CubeSide, GlobalInvocationID);
+    Up = float3(0.0f, 1.0f, 0.0f); // 0.01f offset to 
+    Right = normalize(cross(Up, Forward));
+    Up = normalize(cross(Forward, Right));
+    
+    float3 Irradiance = 0.0f.xxx;
+    float3 IrrDirr = 0.0f.xxx;
+    float SampleStep = 0.025f;
+    float SampleCount = 0.0f;
+  
+    for (float Azimuth = 0.0f; Azimuth < TAU; Azimuth += SampleStep)
+    {
+        for (float Zenith = 0.0f; Zenith < HALF_PI; Zenith += SampleStep)
+        {
+            float3 DirectionTanSpace = float3(sin(Zenith) * cos(Azimuth), sin(Zenith) * sin(Azimuth), cos(Zenith));
+            float3 DirectionWorld = DirectionTanSpace.x * Right + DirectionTanSpace.y * Up + DirectionTanSpace.z * Forward;
+            Irradiance += TextureCubes[pcb.SkyboxHandle].SampleLevel(ImmutableSamplers[pcb.SkyboxHandle], DirectionWorld, 0).xyz * (cos(Zenith) * sin(Zenith));
+            SampleCount++;
+        }
+    }
+    
+    StorageTextureArrays[pcb.OutputTextureHandle][GlobalInvocationID.xyz] = PI * float4(Irradiance * (1.0f / SampleCount), 1.0f);
+}

samples/03_model_render/shader/eqrect_to_cube.cs.hlsl

@@ -1,10 +1,10 @@
-#include "bindless_structs.hlsli"
+#include "ibl_common.hlsli"
 
 struct Block
 {
     uint HdrEnvHandle;
     uint OutputTextureHandle;
-    int CubeSize;
+    int CubeSide;
 };
 
 [[vk::push_constant]]
@@ -33,23 +33,8 @@ float2 SampleSphericalMap(float3 v)
 [numthreads(16, 16, 1)]
 void main(uint3 GlobalInvocationID : SV_DispatchThreadID)
 {
-    float3 LocalDir;
+    float3 LocalDir = GetLocalDir(pcb.CubeSide, GlobalInvocationID);
-    float HalfSide = pcb.CubeSize / 2;
-    float AxisSign = 2.0f * (0.5f - (GlobalInvocationID.z % 2));
     
-    if (GlobalInvocationID.z < 2)
+    float2 UV = SampleSphericalMap(LocalDir);
-    {
-        LocalDir = float3(AxisSign * HalfSide, HalfSide - GlobalInvocationID.y, (HalfSide - GlobalInvocationID.x) * AxisSign);
-    }
-    else if (GlobalInvocationID.z < 4)
-    {
-        LocalDir = float3(GlobalInvocationID.x - HalfSide, AxisSign * HalfSide, AxisSign * (GlobalInvocationID.y - HalfSide));
-    }
-    else
-    {
-        LocalDir = float3((GlobalInvocationID.x - HalfSide) * AxisSign, HalfSide - GlobalInvocationID.y, HalfSide * AxisSign);
-    }
-    
-    float2 UV = SampleSphericalMap(normalize(LocalDir));
     StorageTextureArrays[pcb.OutputTextureHandle][GlobalInvocationID.xyz] = Textures[pcb.HdrEnvHandle].SampleLevel(ImmutableSamplers[pcb.HdrEnvHandle], UV, 0);
 }

samples/03_model_render/shader/ibl_common.hlsli

@@ -0,0 +1,22 @@
+#include "bindless_structs.hlsli"
+
+float3 GetLocalDir(float Side, float3 GlobalInvocationID)
+{
+    float HalfSide = Side / 2;
+    float AxisSign = 2.0f * (0.5f - (GlobalInvocationID.z % 2));
+    
+    float3 LocalDir;
+    if (GlobalInvocationID.z < 2)
+    {
+        LocalDir = float3(AxisSign * HalfSide, HalfSide - GlobalInvocationID.y, (HalfSide - GlobalInvocationID.x) * AxisSign);
+    }
+    else if (GlobalInvocationID.z < 4)
+    {
+        LocalDir = float3(GlobalInvocationID.x - HalfSide, AxisSign * HalfSide, AxisSign * (GlobalInvocationID.y - HalfSide));
+    }
+    else
+    {
+        LocalDir = float3((GlobalInvocationID.x - HalfSide) * AxisSign, HalfSide - GlobalInvocationID.y, HalfSide * AxisSign);
+    }
+    return normalize(LocalDir);
+}