1 files changed, 91 insertions, 46 deletions

diff --git a/Projects/Asteroids/src/asteroids_DE.cpp b/Projects/Asteroids/src/asteroids_DE.cpp
index 35fb0da..ba1dc4d 100644
--- a/Projects/Asteroids/src/asteroids_DE.cpp
+++ b/Projects/Asteroids/src/asteroids_DE.cpp
@@ -73,17 +73,24 @@ namespace Diligent
 
 namespace AsteroidsDE {
 
-struct DrawConstantBuffer {
-    DirectX::XMFLOAT4X4 mWorld;
+struct DrawConstantBuffer
+{
     DirectX::XMFLOAT4X4 mViewProjection;
-    DirectX::XMFLOAT3 mSurfaceColor;
+    DirectX::XMFLOAT4X4 mWorld;
+    DirectX::XMFLOAT3   mSurfaceColor;
     float unused0;
 
     DirectX::XMFLOAT3 mDeepColor;
     float unused1;
+};
 
-    Uint32 mTextureIndex;
-    Uint32 unused3[3];
+struct AsteroidData
+{
+    DirectX::XMFLOAT4X4 mWorld;
+    DirectX::XMFLOAT3   mSurfaceColor;
+    float               unused0;
+    DirectX::XMFLOAT3   mDeepColor;
+    Uint32              mTextureIndex;
 };
 
 struct SkyboxConstantBuffer {
@@ -239,13 +246,30 @@ Asteroids::Asteroids(const Settings &settings, AsteroidsSimulation* asteroids, G
     mBackBufferHeight = mSwapChain->GetDesc().Height;
     const auto MaxAsteroidsInSubset = (NUM_ASTEROIDS + mNumSubsets - 1) / mNumSubsets;
 
+    {
+        BufferDesc desc;
+        desc.Name           = "Asteroids constant buffer";
+        // In bindless mode we will be updating the buffer with UpdateBuffer method
+        desc.Usage          = (m_BindingMode == BindingMode::Bindless) ? USAGE_DEFAULT : USAGE_DYNAMIC;
+        desc.CPUAccessFlags = CPU_ACCESS_WRITE;
+        desc.BindFlags      = BIND_UNIFORM_BUFFER;
+        // In bindless mode, we will only write view-projection matrix
+        desc.uiSizeInBytes  = static_cast<Uint32>( (m_BindingMode == BindingMode::Bindless) ? sizeof(DirectX::XMFLOAT4X4) : sizeof(DrawConstantBuffer) );
+        mDevice->CreateBuffer(desc, nullptr, &mDrawConstantBuffer);
+        if (m_BindingMode != BindingMode::Bindless)
+            Barriers.emplace_back(mDrawConstantBuffer, RESOURCE_STATE_UNKNOWN, RESOURCE_STATE_CONSTANT_BUFFER, true);
+    }
+
     if (m_BindingMode == BindingMode::Bindless)
     {
         {
+            // In Direct3D there is no easy way to pass draw call number into the shader,
+            // so we will use this auxiliary buffer that solely contains integers in ascending order
+            // (0, 1, 2, ...) and we will acess it with FirstInstanceLocation.
             BufferDesc desc;
-            desc.Name      = "Instance ID buffer";
-            desc.Usage     = USAGE_STATIC;
-            desc.BindFlags = BIND_VERTEX_BUFFER;
+            desc.Name          = "Instance ID buffer";
+            desc.Usage         = USAGE_STATIC;
+            desc.BindFlags     = BIND_VERTEX_BUFFER;
             desc.uiSizeInBytes = static_cast<Uint32>(sizeof(Uint32)) * MaxAsteroidsInSubset;
             std::vector<Uint32> Ids(MaxAsteroidsInSubset);
             for (Uint32 i=0; i < Ids.size(); ++i)
@@ -254,14 +278,17 @@ Asteroids::Asteroids(const Settings &settings, AsteroidsSimulation* asteroids, G
             mDevice->CreateBuffer(desc, &Data, &mInstanceIDBuffer);
             Barriers.emplace_back(mInstanceIDBuffer, RESOURCE_STATE_UNKNOWN, RESOURCE_STATE_VERTEX_BUFFER, true);
         }
+
         {
+            // Structured buffer that contains asteroid data. Evey thread needs to use
+            // its own buffer.
             BufferDesc desc;
-            desc.Name      = "Asteroids data buffer";
-            desc.Usage     = USAGE_DYNAMIC;
-            desc.BindFlags = BIND_SHADER_RESOURCE;
-            desc.Mode      = BUFFER_MODE_STRUCTURED;
-            desc.CPUAccessFlags = CPU_ACCESS_WRITE;
-            desc.ElementByteStride = static_cast<Uint32>(sizeof(DrawConstantBuffer));
+            desc.Name              = "Asteroids data buffer";
+            desc.Usage             = USAGE_DYNAMIC;
+            desc.BindFlags         = BIND_SHADER_RESOURCE;
+            desc.Mode              = BUFFER_MODE_STRUCTURED;
+            desc.CPUAccessFlags    = CPU_ACCESS_WRITE;
+            desc.ElementByteStride = static_cast<Uint32>(sizeof(AsteroidData));
             desc.uiSizeInBytes = desc.ElementByteStride * MaxAsteroidsInSubset;
             mAsteroidsDataBuffers.resize(mNumSubsets);
             for(Uint32 i=0; i < mNumSubsets; ++i)
@@ -270,17 +297,6 @@ Asteroids::Asteroids(const Settings &settings, AsteroidsSimulation* asteroids, G
             }
         }
     }
-    else
-    {
-        BufferDesc desc;
-        desc.Name           = "Asteroids constant buffer";
-        desc.Usage          = USAGE_DYNAMIC;
-        desc.CPUAccessFlags = CPU_ACCESS_WRITE;
-        desc.BindFlags      = BIND_UNIFORM_BUFFER;
-        desc.uiSizeInBytes  = (Uint32) sizeof(DrawConstantBuffer);
-        mDevice->CreateBuffer(desc, nullptr, &mDrawConstantBuffer);
-        Barriers.emplace_back(mDrawConstantBuffer, RESOURCE_STATE_UNKNOWN, RESOURCE_STATE_CONSTANT_BUFFER, true);
-    }
 
     // create pipeline state
     {
@@ -293,6 +309,7 @@ Asteroids::Asteroids(const Settings &settings, AsteroidsSimulation* asteroids, G
         };
 
         PSODesc.GraphicsPipeline.InputLayout.LayoutElements = inputDesc;
+        // In bindless mode we will use instance ID buffer as the third input
         PSODesc.GraphicsPipeline.InputLayout.NumElements = (m_BindingMode == BindingMode::Bindless) ? 3 : 2;
 
         PSODesc.GraphicsPipeline.DepthStencilDesc.DepthFunc = COMPARISON_FUNC_GREATER_EQUAL;
@@ -302,8 +319,8 @@ Asteroids::Asteroids(const Settings &settings, AsteroidsSimulation* asteroids, G
             ShaderCreateInfo attribs;
             attribs.Desc.ShaderType = SHADER_TYPE_VERTEX;
             attribs.Desc.Name  = "Asteroids VS";
-            attribs.EntryPoint = "asteroid_vs";
-            attribs.FilePath   = "asteroid_vs.hlsl";
+            attribs.EntryPoint = "asteroid_vs_diligent";
+            attribs.FilePath   = "asteroid_vs_diligent.hlsl";
             attribs.SourceLanguage = SHADER_SOURCE_LANGUAGE_HLSL;
             attribs.pShaderSourceStreamFactory = pShaderSourceFactory;
             attribs.UseCombinedTextureSamplers = true;
@@ -369,29 +386,32 @@ Asteroids::Asteroids(const Settings &settings, AsteroidsSimulation* asteroids, G
 
         PSODesc.GraphicsPipeline.pVS = vs;
         PSODesc.GraphicsPipeline.pPS = ps;
+        mDevice->CreatePipelineState(PSODesc, &mAsteroidsPSO);
+        mAsteroidsPSO->GetStaticVariableByName(SHADER_TYPE_VERTEX, "DrawConstantBuffer")->Set(mDrawConstantBuffer);
+
         Uint32 NumSRBs = 0;
         if(m_BindingMode == BindingMode::Dynamic)
         {
+            // Create one SRB per subset for dynamic binding mode
             NumSRBs = mNumSubsets;
         }
         else if(m_BindingMode == BindingMode::Mutable)
         {
+            // Create one SRB per asteroid in mutable binding mode
             PSODesc.SRBAllocationGranularity = 1024;
             NumSRBs = NUM_ASTEROIDS;
         }
         else if(m_BindingMode == BindingMode::TextureMutable)
         {
+            // Create one SRB per texture in texture-mutable binding mode
             PSODesc.SRBAllocationGranularity = NUM_UNIQUE_TEXTURES;
             NumSRBs = NUM_UNIQUE_TEXTURES;
         }
         else if(m_BindingMode == BindingMode::Bindless)
         {
+            // Create one SRB per subset for bindless mode
             NumSRBs = mNumSubsets;
         }
-        mDevice->CreatePipelineState(PSODesc, &mAsteroidsPSO);
-        if (m_BindingMode != BindingMode::Bindless)
-            mAsteroidsPSO->GetStaticVariableByName(SHADER_TYPE_VERTEX, "DrawConstantBuffer")->Set(mDrawConstantBuffer);
-
         mAsteroidsSRBs.resize(NumSRBs);
         for(size_t srb = 0; srb < mAsteroidsSRBs.size(); ++srb)
         {
@@ -583,6 +603,7 @@ Asteroids::Asteroids(const Settings &settings, AsteroidsSimulation* asteroids, G
     InitializeTextureData();
     if( m_BindingMode == BindingMode::Mutable )
     {
+        // Bind the corresponding texture to the asteroids's SRB
         for(size_t srb = 0; srb < NUM_ASTEROIDS; ++srb)
         {
             auto staticData = &mAsteroids->StaticData()[srb];
@@ -591,6 +612,7 @@ Asteroids::Asteroids(const Settings &settings, AsteroidsSimulation* asteroids, G
     }
     else if( m_BindingMode == BindingMode::TextureMutable )
     {
+        // Bind the corresponding texture to the textures's SRB
         for(size_t srb = 0; srb < NUM_UNIQUE_TEXTURES; ++srb)
         {
             mAsteroidsSRBs[srb]->GetVariableByName(SHADER_TYPE_PIXEL, "Tex")->Set(mTextureSRVs[srb]);
@@ -598,6 +620,7 @@ Asteroids::Asteroids(const Settings &settings, AsteroidsSimulation* asteroids, G
     }
     else if( m_BindingMode == BindingMode::Bindless )
     {
+        // Bind all textures to every subset's SRB. The textures will be dynamically indexed in the shader.
         IDeviceObject* SRVArray[NUM_UNIQUE_TEXTURES];
         for(Uint32 t = 0; t < NUM_UNIQUE_TEXTURES; ++t)
             SRVArray[t] = mTextureSRVs[t];
@@ -624,7 +647,6 @@ Asteroids::~Asteroids()
 }
 
 
-
 void Asteroids::ResizeSwapChain(HWND outputWindow, unsigned int width, unsigned int height)
 {
     mSwapChain->Resize(width, height);
@@ -833,32 +855,37 @@ void Asteroids::RenderSubset(Diligent::Uint32 SubsetNum,
     {
         IBuffer* ia_buffers[] = { mVertexBuffer, mInstanceIDBuffer };
         Uint32 ia_offsets[_countof(ia_buffers)] = {};
+        // Bind instance data buffer in bindless mode
         pCtx->SetVertexBuffers(0, (m_BindingMode == BindingMode::Bindless) ? 2 : 1, ia_buffers, ia_offsets, RESOURCE_STATE_TRANSITION_MODE_VERIFY, SET_VERTEX_BUFFERS_FLAG_NONE);
         pCtx->SetIndexBuffer(mIndexBuffer, 0, RESOURCE_STATE_TRANSITION_MODE_VERIFY);
     }
 
-    auto viewProjection = camera.ViewProjection();
-    
     if (m_BindingMode == BindingMode::Bindless)
     {
         {
-            MapHelper<DrawConstantBuffer> drawConstants(pCtx, mAsteroidsDataBuffers[SubsetNum], MAP_WRITE, MAP_FLAG_DISCARD);
+            // Update asteroid data buffer
+            MapHelper<AsteroidData> asteroidData(pCtx, mAsteroidsDataBuffers[SubsetNum], MAP_WRITE, MAP_FLAG_DISCARD);
             UINT i=0;
             for (UINT drawIdx = startIdx; drawIdx < startIdx+numAsteroids; ++drawIdx, ++i)
             {
                 const auto staticData = &staticAsteroidData[drawIdx];
                 const auto dynamicData = &dynamicAsteroidData[drawIdx];
 
-                XMStoreFloat4x4(&drawConstants[i].mWorld,          dynamicData->world);
-                XMStoreFloat4x4(&drawConstants[i].mViewProjection, viewProjection);
-                drawConstants[i].mSurfaceColor = staticData->surfaceColor;
-                drawConstants[i].mDeepColor    = staticData->deepColor;
-                drawConstants[i].mTextureIndex = staticData->textureIndex;
+                XMStoreFloat4x4(&asteroidData[i].mWorld, dynamicData->world);
+                asteroidData[i].mSurfaceColor = staticData->surfaceColor;
+                asteroidData[i].mDeepColor    = staticData->deepColor;
+                asteroidData[i].mTextureIndex = staticData->textureIndex;
             }
         }
-        pCtx->CommitShaderResources(mAsteroidsSRBs[SubsetNum], RESOURCE_STATE_TRANSITION_MODE_TRANSITION);
+
+        StateTransitionDesc Barrier{mAsteroidsDataBuffers[SubsetNum], RESOURCE_STATE_UNKNOWN, RESOURCE_STATE_SHADER_RESOURCE, true};
+        pCtx->TransitionResourceStates(1, &Barrier);
+
+        // Commit and verify resources
+        pCtx->CommitShaderResources(mAsteroidsSRBs[SubsetNum], RESOURCE_STATE_TRANSITION_MODE_VERIFY);
     }
        
+    const auto& viewProjection = camera.ViewProjection();
     auto pVar = m_BindingMode == BindingMode::Dynamic ? mAsteroidsSRBs[SubsetNum]->GetVariableByName(SHADER_TYPE_PIXEL, "Tex") : nullptr;
     for (UINT drawIdx = startIdx; drawIdx < startIdx+numAsteroids; ++drawIdx)
     {
@@ -872,8 +899,8 @@ void Asteroids::RenderSubset(Diligent::Uint32 SubsetNum,
             XMStoreFloat4x4(&drawConstants->mViewProjection, viewProjection);
             drawConstants->mSurfaceColor = staticData->surfaceColor;
             drawConstants->mDeepColor    = staticData->deepColor;
-            drawConstants->mTextureIndex = staticData->textureIndex;
         }
+        // No need to update the buffer in bindless mode
 
         if( m_BindingMode == BindingMode::Dynamic )
         {
@@ -891,8 +918,16 @@ void Asteroids::RenderSubset(Diligent::Uint32 SubsetNum,
 
         DrawIndexedAttribs attribs(dynamicData->indexCount, VT_UINT16, DRAW_FLAG_VERIFY_ALL);
         attribs.FirstIndexLocation = dynamicData->indexStart;
-        attribs.BaseVertex = staticData->vertexStart;
-        attribs.FirstInstanceLocation = drawIdx - startIdx;
+        attribs.BaseVertex         = staticData->vertexStart;
+
+        if( m_BindingMode == BindingMode::Bindless )
+        {
+            // It is very important to speciy this flag to make sure the engine does not do extra
+            // work processing buffers that stay intact.
+            attribs.Flags |= DRAW_FLAG_RESOURCE_BUFFERS_INTACT;
+            attribs.FirstInstanceLocation = drawIdx - startIdx;
+        }
+
         pCtx->DrawIndexed(attribs);
     }
 }
@@ -915,13 +950,23 @@ void Asteroids::Render(float frameTime, const OrbitCamera& camera, const Setting
         
     auto SubsetSize = NUM_ASTEROIDS / mNumSubsets;
     
+    if (m_BindingMode == BindingMode::Bindless)
+    {
+        // Write view-projection matrix into the buffer
+        const auto& viewProjection = camera.ViewProjection();
+        mDeviceCtxt->UpdateBuffer(mDrawConstantBuffer, 0, sizeof(DirectX::XMFLOAT4X4), (void*)&viewProjection, RESOURCE_STATE_TRANSITION_MODE_TRANSITION);
+        // Explicitly transition the buffer to CONSTANT_BUFFER state
+        StateTransitionDesc Barrier{mDrawConstantBuffer, RESOURCE_STATE_UNKNOWN, RESOURCE_STATE_CONSTANT_BUFFER, true};
+        mDeviceCtxt->TransitionResourceStates(1, &Barrier);
+    }
+
     if (settings.multithreadedRendering)
     {
         m_NumThreadsCompleted = 0;
         mUpdateSubsetsSignal.Trigger(true);
     }
 
-
+    // Update all subsets in this thread when multithreadedRendering is false
     for(Uint32 i=0; i < (!settings.multithreadedRendering ? mNumSubsets : 1); ++i)
         mAsteroids->Update(frameTime, camera.Eye(), settings, SubsetSize * i, SubsetSize);
 
@@ -933,7 +978,6 @@ void Asteroids::Render(float frameTime, const OrbitCamera& camera, const Setting
         // Reset mUpdateSubsetsSignal while all threads are waiting for mRenderSubsetsSignal
         mUpdateSubsetsSignal.Reset();
     }
-    
 
     QueryPerformanceCounter((LARGE_INTEGER*)&currCounter);
     mUpdateTicks = currCounter-mUpdateTicks;
@@ -947,6 +991,7 @@ void Asteroids::Render(float frameTime, const OrbitCamera& camera, const Setting
         mRenderSubsetsSignal.Trigger(true);
     }
 
+    // Render all subsets in this thread when multithreadedRendering is false
     for(Uint32 i=0; i < (!settings.multithreadedRendering ? mNumSubsets : 1); ++i)
         RenderSubset(i, mDeviceCtxt, camera, SubsetSize * i, SubsetSize);