Hydrogent: reworked selection outline to use separate render target

Hydrogent/interface/HnTokens.hpp

@@ -105,6 +105,7 @@ namespace USD
     (offscreenColorTarget)        \
     (finalColorTarget)            \
     (meshIdTarget)                \
+    (selectionTarget)             \
     (depthBuffer)
 
 // clang-format on

Hydrogent/interface/Tasks/HnSetupRenderingTask.hpp

@@ -76,9 +76,10 @@ struct HnSetupRenderingTaskParams
         return !(*this == rhs);
     }
 
-    TEXTURE_FORMAT ColorFormat  = TEX_FORMAT_UNKNOWN;
-    TEXTURE_FORMAT MeshIdFormat = TEX_FORMAT_UNKNOWN;
-    TEXTURE_FORMAT DepthFormat  = TEX_FORMAT_UNKNOWN;
+    TEXTURE_FORMAT ColorFormat     = TEX_FORMAT_RGBA16_FLOAT;
+    TEXTURE_FORMAT MeshIdFormat    = TEX_FORMAT_R32_FLOAT;
+    TEXTURE_FORMAT SelectionFormat = TEX_FORMAT_R8_UNORM;
+    TEXTURE_FORMAT DepthFormat     = TEX_FORMAT_D32_FLOAT;
 
     bool FrontFaceCCW = false;
 
@@ -140,6 +141,7 @@ class HnSetupRenderingTask final : public HnTask
     pxr::SdfPath m_FinalColorTargetId;
     pxr::SdfPath m_OffscreenColorTargetId;
     pxr::SdfPath m_MeshIdTargetId;
+    pxr::SdfPath m_SelectionTargetId;
     pxr::SdfPath m_DepthBufferId;
 
     float4 m_ClearColor;
@@ -149,6 +151,7 @@ class HnSetupRenderingTask final : public HnTask
 
     ITextureView* m_pFinalColorRTV = nullptr;
     ITextureView* m_pMeshIdRTV     = nullptr;
+    ITextureView* m_pSelectionRTV  = nullptr;
     ITextureView* m_pDepthDSV      = nullptr;
 };
 

Hydrogent/shaders/HnPostProcess.psh

@@ -12,7 +12,7 @@ cbuffer cbPostProcessAttribs
 }
 
 Texture2D g_ColorBuffer;
-Texture2D g_MeshId;
+Texture2D g_Selection;
 
 void main(in PSInput PSIn,
           out float4 Color : SV_Target0)
@@ -24,21 +24,20 @@ void main(in PSInput PSIn,
 #endif
 
     // Selected rprim is rendered with negative index
-    float IsSelected0 = g_MeshId.Load(int3(PSIn.Pos.xy + float2(-1.0, -1.0), 0)).r < 0.0 ? -1.0 : +1.0;
-    float IsSelected1 = g_MeshId.Load(int3(PSIn.Pos.xy + float2( 0.0, -1.0), 0)).r < 0.0 ? -1.0 : +1.0;
-    float IsSelected2 = g_MeshId.Load(int3(PSIn.Pos.xy + float2(+1.0, -1.0), 0)).r < 0.0 ? -1.0 : +1.0;
+    float IsSelected0 = g_Selection.Load(int3(PSIn.Pos.xy + float2(-1.0, -1.0), 0)).r;
+    float IsSelected1 = g_Selection.Load(int3(PSIn.Pos.xy + float2( 0.0, -1.0), 0)).r;
+    float IsSelected2 = g_Selection.Load(int3(PSIn.Pos.xy + float2(+1.0, -1.0), 0)).r;
 
-    float IsSelected3 = g_MeshId.Load(int3(PSIn.Pos.xy + float2(-1.0,  0.0), 0)).r < 0.0 ? -1.0 : +1.0;
-    float IsSelected4 = g_MeshId.Load(int3(PSIn.Pos.xy + float2( 0.0,  0.0), 0)).r < 0.0 ? -1.0 : +1.0;
-    float IsSelected5 = g_MeshId.Load(int3(PSIn.Pos.xy + float2(+1.0,  0.0), 0)).r < 0.0 ? -1.0 : +1.0;
+    float IsSelected3 = g_Selection.Load(int3(PSIn.Pos.xy + float2(-1.0,  0.0), 0)).r;
+    float IsSelected4 = g_Selection.Load(int3(PSIn.Pos.xy + float2( 0.0,  0.0), 0)).r;
+    float IsSelected5 = g_Selection.Load(int3(PSIn.Pos.xy + float2(+1.0,  0.0), 0)).r;
 
-    float IsSelected6 = g_MeshId.Load(int3(PSIn.Pos.xy + float2(-1.0, +1.0), 0)).r < 0.0 ? -1.0 : +1.0;
-    float IsSelected7 = g_MeshId.Load(int3(PSIn.Pos.xy + float2( 0.0, +1.0), 0)).r < 0.0 ? -1.0 : +1.0;
-    float IsSelected8 = g_MeshId.Load(int3(PSIn.Pos.xy + float2(+1.0, +1.0), 0)).r < 0.0 ? -1.0 : +1.0;
+    float IsSelected6 = g_Selection.Load(int3(PSIn.Pos.xy + float2(-1.0, +1.0), 0)).r;
+    float IsSelected7 = g_Selection.Load(int3(PSIn.Pos.xy + float2( 0.0, +1.0), 0)).r;
+    float IsSelected8 = g_Selection.Load(int3(PSIn.Pos.xy + float2(+1.0, +1.0), 0)).r;
 
     float Outline = IsSelected0 + IsSelected1 + IsSelected2 + IsSelected3 + IsSelected4 + IsSelected5 + IsSelected6 + IsSelected7 + IsSelected8;
-    //Outline = (9.0 - Outline) * (Outline > 0.0 ? 1.0 / 8.0 : 0.0);
-    Outline = (Outline > 0.0 && Outline < 9.0) ? 1.0 : 0.0;
+    Outline = (Outline > 4.0 && Outline < 9.0) ? 1.0 : 0.0;
 
     float DesatFactor = g_Attribs.NonselectionDesaturationFactor * saturate(IsSelected4);
     float Luminance = dot(Color.rgb, float3(0.2126, 0.7152, 0.0722));

Hydrogent/shaders_inc/HnPostProcess.psh.h

@@ -12,7 +12,7 @@
 "}\n"
 "\n"
 "Texture2D g_ColorBuffer;\n"
-"Texture2D g_MeshId;\n"
+"Texture2D g_Selection;\n"
 "\n"
 "void main(in PSInput PSIn,\n"
 "          out float4 Color : SV_Target0)\n"
@@ -24,21 +24,20 @@
 "#endif\n"
 "\n"
 "    // Selected rprim is rendered with negative index\n"
-"    float IsSelected0 = g_MeshId.Load(int3(PSIn.Pos.xy + float2(-1.0, -1.0), 0)).r < 0.0 ? -1.0 : +1.0;\n"
-"    float IsSelected1 = g_MeshId.Load(int3(PSIn.Pos.xy + float2( 0.0, -1.0), 0)).r < 0.0 ? -1.0 : +1.0;\n"
-"    float IsSelected2 = g_MeshId.Load(int3(PSIn.Pos.xy + float2(+1.0, -1.0), 0)).r < 0.0 ? -1.0 : +1.0;\n"
+"    float IsSelected0 = g_Selection.Load(int3(PSIn.Pos.xy + float2(-1.0, -1.0), 0)).r;\n"
+"    float IsSelected1 = g_Selection.Load(int3(PSIn.Pos.xy + float2( 0.0, -1.0), 0)).r;\n"
+"    float IsSelected2 = g_Selection.Load(int3(PSIn.Pos.xy + float2(+1.0, -1.0), 0)).r;\n"
 "\n"
-"    float IsSelected3 = g_MeshId.Load(int3(PSIn.Pos.xy + float2(-1.0,  0.0), 0)).r < 0.0 ? -1.0 : +1.0;\n"
-"    float IsSelected4 = g_MeshId.Load(int3(PSIn.Pos.xy + float2( 0.0,  0.0), 0)).r < 0.0 ? -1.0 : +1.0;\n"
-"    float IsSelected5 = g_MeshId.Load(int3(PSIn.Pos.xy + float2(+1.0,  0.0), 0)).r < 0.0 ? -1.0 : +1.0;\n"
+"    float IsSelected3 = g_Selection.Load(int3(PSIn.Pos.xy + float2(-1.0,  0.0), 0)).r;\n"
+"    float IsSelected4 = g_Selection.Load(int3(PSIn.Pos.xy + float2( 0.0,  0.0), 0)).r;\n"
+"    float IsSelected5 = g_Selection.Load(int3(PSIn.Pos.xy + float2(+1.0,  0.0), 0)).r;\n"
 "\n"
-"    float IsSelected6 = g_MeshId.Load(int3(PSIn.Pos.xy + float2(-1.0, +1.0), 0)).r < 0.0 ? -1.0 : +1.0;\n"
-"    float IsSelected7 = g_MeshId.Load(int3(PSIn.Pos.xy + float2( 0.0, +1.0), 0)).r < 0.0 ? -1.0 : +1.0;\n"
-"    float IsSelected8 = g_MeshId.Load(int3(PSIn.Pos.xy + float2(+1.0, +1.0), 0)).r < 0.0 ? -1.0 : +1.0;\n"
+"    float IsSelected6 = g_Selection.Load(int3(PSIn.Pos.xy + float2(-1.0, +1.0), 0)).r;\n"
+"    float IsSelected7 = g_Selection.Load(int3(PSIn.Pos.xy + float2( 0.0, +1.0), 0)).r;\n"
+"    float IsSelected8 = g_Selection.Load(int3(PSIn.Pos.xy + float2(+1.0, +1.0), 0)).r;\n"
 "\n"
 "    float Outline = IsSelected0 + IsSelected1 + IsSelected2 + IsSelected3 + IsSelected4 + IsSelected5 + IsSelected6 + IsSelected7 + IsSelected8;\n"
-"    //Outline = (9.0 - Outline) * (Outline > 0.0 ? 1.0 / 8.0 : 0.0);\n"
-"    Outline = (Outline > 0.0 && Outline < 9.0) ? 1.0 : 0.0;\n"
+"    Outline = (Outline > 4.0 && Outline < 9.0) ? 1.0 : 0.0;\n"
 "\n"
 "    float DesatFactor = g_Attribs.NonselectionDesaturationFactor * saturate(IsSelected4);\n"
 "    float Luminance = dot(Color.rgb, float3(0.2126, 0.7152, 0.0722));\n"

Hydrogent/src/HnRenderDelegate.cpp

@@ -62,6 +62,30 @@ const pxr::TfTokenVector HnRenderDelegate::SupportedBPrimTypes =
 };
 // clang-format on
 
+static std::string GetPbrPSMainSource(USD_Renderer::PSO_FLAGS PSOFlags)
+{
+    VERIFY(PSOFlags & USD_Renderer::PSO_FLAG_ENABLE_CUSTOM_DATA_OUTPUT, "Custom output flag is expected to be set");
+    return R"(
+struct PSOutput
+{
+    float4 Color      : SV_Target0;
+    float4 MeshID     : SV_Target1;
+    float4 IsSelected : SV_Target2;
+};
+
+void main(in VSOutput VSOut,
+          in bool IsFrontFace : SV_IsFrontFace,
+          out PSOutput PSOut)
+{
+    PSOut.Color = ComputePbrSurfaceColor(VSOut, IsFrontFace);
+
+    // It is important to set alpha to 1.0 as all targets are rendered with the same blend mode
+    PSOut.MeshID     = float4(g_PBRAttribs.Renderer.CustomData.x, 0.0, 0.0, 1.0);
+    PSOut.IsSelected = float4(g_PBRAttribs.Renderer.CustomData.y, 0.0, 0.0, 1.0);
+}
+)";
+}
+
 HnRenderDelegate::HnRenderDelegate(const CreateInfo& CI) :
     m_pDevice{CI.pDevice},
     m_pContext{CI.pContext},
@@ -94,6 +118,8 @@ HnRenderDelegate::HnRenderDelegate(const CreateInfo& CI) :
                 USDRendererCI.InputLayout.LayoutElements = Inputs;
                 USDRendererCI.InputLayout.NumElements    = _countof(Inputs);
 
+                USDRendererCI.GetPSMainSource = GetPbrPSMainSource;
+
                 return USDRendererCI;
             }()),
     },

Hydrogent/src/HnRenderPass.cpp

@@ -331,10 +331,12 @@ void HnRenderPass::RenderMesh(RenderState&      State,
         RendererParams.MiddleGray    = 0.18f;
         RendererParams.WhitePoint    = 3.0f;
 
-        auto CustomData = float4{static_cast<float>(Mesh.GetUID()), 0, 0, 1};
-        if (Mesh.GetId().HasPrefix(m_Params.SelectedPrimId))
-            CustomData.x *= -1;
-        RendererParams.CustomData = CustomData;
+        RendererParams.CustomData = float4{
+            static_cast<float>(Mesh.GetUID()),
+            Mesh.GetId().HasPrefix(m_Params.SelectedPrimId) ? 1.f : 0.f,
+            0,
+            0,
+        };
     }
 
     State.pCtx->CommitShaderResources(pSRB, RESOURCE_STATE_TRANSITION_MODE_TRANSITION);

Hydrogent/src/Tasks/HnPostProcessTask.cpp

@@ -134,7 +134,7 @@ void HnPostProcessTask::PreparePSO(TEXTURE_FORMAT RTVFormat)
     PipelineResourceLayoutDescX ResourceLauout;
     ResourceLauout
         .AddVariable(SHADER_TYPE_PIXEL, "g_ColorBuffer", SHADER_RESOURCE_VARIABLE_TYPE_DYNAMIC)
-        .AddVariable(SHADER_TYPE_PIXEL, "g_MeshId", SHADER_RESOURCE_VARIABLE_TYPE_DYNAMIC);
+        .AddVariable(SHADER_TYPE_PIXEL, "g_Selection", SHADER_RESOURCE_VARIABLE_TYPE_DYNAMIC);
 
     GraphicsPipelineStateCreateInfoX PsoCI{"Post process"};
     PsoCI
@@ -229,8 +229,8 @@ void HnPostProcessTask::Execute(pxr::HdTaskContext* TaskCtx)
         UNEXPECTED("Offscreen color RTV is not set in the task context");
         return;
     }
-    ITextureView* pMeshIdRTV = GetRenderBufferTarget(*m_RenderIndex, TaskCtx, HnRenderResourceTokens->meshIdTarget);
-    if (pMeshIdRTV == nullptr)
+    ITextureView* pSelectionRTV = GetRenderBufferTarget(*m_RenderIndex, TaskCtx, HnRenderResourceTokens->selectionTarget);
+    if (pSelectionRTV == nullptr)
     {
         UNEXPECTED("Mesh Id RTV is not set in the task context");
         return;
@@ -241,8 +241,8 @@ void HnPostProcessTask::Execute(pxr::HdTaskContext* TaskCtx)
         UNEXPECTED("Offscreen color SRV is null");
         return;
     }
-    ITextureView* pMeshIdSRV = pMeshIdRTV->GetTexture()->GetDefaultView(TEXTURE_VIEW_SHADER_RESOURCE);
-    if (pMeshIdSRV == nullptr)
+    ITextureView* pSelectionSRV = pSelectionRTV->GetTexture()->GetDefaultView(TEXTURE_VIEW_SHADER_RESOURCE);
+    if (pSelectionSRV == nullptr)
     {
         UNEXPECTED("Mesh Id SRV is null");
         return;
@@ -269,7 +269,7 @@ void HnPostProcessTask::Execute(pxr::HdTaskContext* TaskCtx)
     }
     pCtx->SetPipelineState(m_PSO);
     m_SRB->GetVariableByName(SHADER_TYPE_PIXEL, "g_ColorBuffer")->Set(pOffscreenColorSRV);
-    m_SRB->GetVariableByName(SHADER_TYPE_PIXEL, "g_MeshId")->Set(pMeshIdSRV);
+    m_SRB->GetVariableByName(SHADER_TYPE_PIXEL, "g_Selection")->Set(pSelectionSRV);
     pCtx->CommitShaderResources(m_SRB, RESOURCE_STATE_TRANSITION_MODE_TRANSITION);
     pCtx->Draw({3, DRAW_FLAG_VERIFY_ALL});
 }

Hydrogent/src/Tasks/HnReadRprimIdTask.cpp

@@ -113,7 +113,7 @@ void HnReadRprimIdTask::Execute(pxr::HdTaskContext* TaskCtx)
         {
             MappedTextureSubresource MappedData;
             pCtx->MapTextureSubresource(pStagingTex, 0, 0, MAP_READ, MAP_FLAG_DO_NOT_WAIT, nullptr, MappedData);
-            m_MeshIndex = static_cast<Uint32>(std::abs(*static_cast<const float*>(MappedData.pData)));
+            m_MeshIndex = static_cast<Uint32>(*static_cast<const float*>(MappedData.pData));
             pCtx->UnmapTextureSubresource(pStagingTex, 0, 0);
         }
         m_MeshIdReadBackQueue->Recycle(std::move(pStagingTex));

Hydrogent/src/Tasks/HnSetupRenderingTask.cpp

@@ -55,6 +55,7 @@ HnSetupRenderingTask::HnSetupRenderingTask(pxr::HdSceneDelegate* ParamsDelegate,
     };
     m_OffscreenColorTargetId = InitBrim(HnRenderResourceTokens->offscreenColorTarget);
     m_MeshIdTargetId         = InitBrim(HnRenderResourceTokens->meshIdTarget);
+    m_SelectionTargetId      = InitBrim(HnRenderResourceTokens->selectionTarget);
     m_DepthBufferId          = InitBrim(HnRenderResourceTokens->depthBuffer);
 }
 
@@ -65,9 +66,10 @@ HnSetupRenderingTask::~HnSetupRenderingTask()
 void HnSetupRenderingTask::UpdateRenderPassState(const HnSetupRenderingTaskParams& Params)
 {
     VERIFY_EXPR(Params.ColorFormat != TEX_FORMAT_UNKNOWN);
-    m_RenderPassState->SetNumRenderTargets(Params.MeshIdFormat != TEX_FORMAT_UNKNOWN ? 2 : 1);
+    m_RenderPassState->SetNumRenderTargets(3);
     m_RenderPassState->SetRenderTargetFormat(0, Params.ColorFormat);
     m_RenderPassState->SetRenderTargetFormat(1, Params.MeshIdFormat);
+    m_RenderPassState->SetRenderTargetFormat(2, Params.SelectionFormat);
     m_RenderPassState->SetDepthStencilFormat(Params.DepthFormat);
 
     m_RenderPassState->SetDepthBias(Params.DepthBias, Params.SlopeScaledDepthBias);
@@ -120,6 +122,8 @@ void HnSetupRenderingTask::PrepareRenderTargets(pxr::HdRenderIndex* RenderIndex,
         if (Format == TEX_FORMAT_UNKNOWN)
             return nullptr;
 
+        VERIFY_EXPR(!Id.IsEmpty());
+
         HnRenderBuffer* Renderbuffer = static_cast<HnRenderBuffer*>(RenderIndex->GetBprim(pxr::HdPrimTypeTokens->renderBuffer, Id));
         if (Renderbuffer == nullptr)
         {
@@ -163,6 +167,7 @@ void HnSetupRenderingTask::PrepareRenderTargets(pxr::HdRenderIndex* RenderIndex,
     };
     m_pFinalColorRTV = UpdateBrim(m_OffscreenColorTargetId, m_RenderPassState->GetRenderTargetFormat(0), "Offscreen color target");
     m_pMeshIdRTV     = UpdateBrim(m_MeshIdTargetId, m_RenderPassState->GetRenderTargetFormat(1), "Mesh Id target");
+    m_pSelectionRTV  = UpdateBrim(m_SelectionTargetId, m_RenderPassState->GetRenderTargetFormat(2), "Selection target");
     m_pDepthDSV      = UpdateBrim(m_DepthBufferId, m_RenderPassState->GetDepthStencilFormat(), "Depth buffer");
 }
 
@@ -173,6 +178,7 @@ void HnSetupRenderingTask::Prepare(pxr::HdTaskContext* TaskCtx,
     (*TaskCtx)[HnRenderResourceTokens->finalColorTarget]     = pxr::VtValue{m_FinalColorTargetId};
     (*TaskCtx)[HnRenderResourceTokens->offscreenColorTarget] = pxr::VtValue{m_OffscreenColorTargetId};
     (*TaskCtx)[HnRenderResourceTokens->meshIdTarget]         = pxr::VtValue{m_MeshIdTargetId};
+    (*TaskCtx)[HnRenderResourceTokens->selectionTarget]      = pxr::VtValue{m_SelectionTargetId};
 
     if (ITextureView* pFinalColorRTV = GetRenderBufferTarget(*RenderIndex, m_FinalColorTargetId))
     {
@@ -194,14 +200,15 @@ void HnSetupRenderingTask::Execute(pxr::HdTaskContext* TaskCtx)
         return;
     }
 
-    ITextureView* pRTVs[] = {m_pFinalColorRTV, m_pMeshIdRTV};
+    ITextureView* pRTVs[] = {m_pFinalColorRTV, m_pMeshIdRTV, m_pSelectionRTV};
 
     auto* pCtx = static_cast<HnRenderDelegate*>(m_RenderIndex->GetRenderDelegate())->GetDeviceContext();
 
     pCtx->SetRenderTargets(_countof(pRTVs), pRTVs, m_pDepthDSV, RESOURCE_STATE_TRANSITION_MODE_TRANSITION);
-    pCtx->ClearRenderTarget(pRTVs[0], m_ClearColor.Data(), RESOURCE_STATE_TRANSITION_MODE_TRANSITION);
+    pCtx->ClearRenderTarget(m_pFinalColorRTV, m_ClearColor.Data(), RESOURCE_STATE_TRANSITION_MODE_TRANSITION);
     constexpr float Zero[] = {0, 0, 0, 0};
-    pCtx->ClearRenderTarget(pRTVs[1], Zero, RESOURCE_STATE_TRANSITION_MODE_TRANSITION);
+    pCtx->ClearRenderTarget(m_pMeshIdRTV, Zero, RESOURCE_STATE_TRANSITION_MODE_TRANSITION);
+    pCtx->ClearRenderTarget(m_pSelectionRTV, Zero, RESOURCE_STATE_TRANSITION_MODE_TRANSITION);
     pCtx->ClearDepthStencil(m_pDepthDSV, CLEAR_DEPTH_FLAG, m_ClearDepth, 0, RESOURCE_STATE_TRANSITION_MODE_TRANSITION);
     pCtx->SetStencilRef(m_RenderPassState->GetStencilRef());
 }

PBR/interface/PBR_Renderer.hpp

@@ -135,7 +135,7 @@ class PBR_Renderer
         /// An optional user-provided callback function that is used to generate the pixel
         /// shader's main function source code for the specified PSO flags. If null, the renderer
         /// will use the default implementation.
-        std::function<std::string(PSO_FLAGS PsoFlags)> GetPSMainShaderSource = nullptr;
+        std::function<std::string(PSO_FLAGS PsoFlags)> GetPSMainSource = nullptr;
     };
 
     enum ALPHA_MODE

PBR/src/PBR_Renderer.cpp

@@ -818,9 +818,9 @@ void PBR_Renderer::CreateShaders(PSO_FLAGS               PSOFlags,
 
     std::string PSMainSource;
 
-    if (m_Settings.GetPSMainShaderSource)
+    if (m_Settings.GetPSMainSource)
     {
-        PSMainSource = m_Settings.GetPSMainShaderSource(PSOFlags);
+        PSMainSource = m_Settings.GetPSMainSource(PSOFlags);
     }
     else
     {