Execute viewport offscreen frames through D3D12 host

new_editor/app/Application.cpp

@@ -464,8 +464,18 @@ bool Application::Initialize(HINSTANCE hInstance, int nCmdShow) {
         LogRuntimeTrace("app", "renderer initialization failed");
         return false;
     }
+    RECT clientRect = {};
+    GetClientRect(m_hwnd, &clientRect);
+    const int clientWidth = (std::max)(clientRect.right - clientRect.left, 1L);
+    const int clientHeight = (std::max)(clientRect.bottom - clientRect.top, 1L);
+    if (!m_windowRenderer.Initialize(m_hwnd, clientWidth, clientHeight)) {
+        LogRuntimeTrace("app", "d3d12 window renderer initialization failed");
+        return false;
+    }
     m_editorContext.AttachTextMeasurer(m_renderer);
     m_editorWorkspace.Initialize(repoRoot, m_renderer);
+    m_editorWorkspace.AttachViewportWindowRenderer(m_windowRenderer);
+    m_editorWorkspace.SetViewportSurfacePresentationEnabled(false);
     if (!m_editorWorkspace.GetBuiltInIconError().empty()) {
         LogRuntimeTrace("icons", m_editorWorkspace.GetBuiltInIconError());
     }
@@ -494,6 +504,7 @@ void Application::Shutdown() {
 
     m_autoScreenshot.Shutdown();
     m_editorWorkspace.Shutdown();
+    m_windowRenderer.Shutdown();
     m_renderer.Shutdown();
 
     if (m_hwnd != nullptr && IsWindow(m_hwnd)) {
@@ -541,11 +552,22 @@ void Application::RenderFrame() {
                         m_editorWorkspace.GetShellInteractionState()));
         }
 
+        const bool d3d12FrameBegun = m_windowRenderer.BeginFrame();
+        if (!d3d12FrameBegun) {
+            LogRuntimeTrace("viewport", "d3d12 frame begin failed");
+        }
+
         m_editorWorkspace.Update(
             m_editorContext,
             UIRect(0.0f, 0.0f, width, height),
             frameEvents,
             BuildCaptureStatusText());
+        if (d3d12FrameBegun) {
+            m_editorWorkspace.RenderRequestedViewports(m_windowRenderer.GetRenderContext());
+            if (!m_windowRenderer.SubmitFrame(false)) {
+                LogRuntimeTrace("viewport", "d3d12 offscreen frame submit failed");
+            }
+        }
         const UIEditorShellInteractionFrame& shellFrame =
             m_editorWorkspace.GetShellFrame();
         if (!frameEvents.empty() ||
@@ -710,6 +732,7 @@ void Application::OnResize(UINT width, UINT height) {
     }
 
     m_renderer.Resize(width, height);
+    m_windowRenderer.Resize(static_cast<int>(width), static_cast<int>(height));
 }
 
 void Application::OnDpiChanged(UINT dpi, const RECT& suggestedRect) {

new_editor/app/Application.h

@@ -5,6 +5,7 @@
 #endif
 
 #include <Host/AutoScreenshot.h>
+#include <Host/D3D12WindowRenderer.h>
 #include <Host/InputModifierTracker.h>
 #include <Host/NativeRenderer.h>
 
@@ -68,6 +69,7 @@ private:
     HINSTANCE m_hInstance = nullptr;
     ATOM m_windowClassAtom = 0;
     ::XCEngine::UI::Editor::Host::NativeRenderer m_renderer = {};
+    ::XCEngine::UI::Editor::Host::D3D12WindowRenderer m_windowRenderer = {};
     ::XCEngine::UI::Editor::Host::AutoScreenshotController m_autoScreenshot = {};
     ::XCEngine::UI::Editor::Host::InputModifierTracker m_inputModifierTracker = {};
     App::ProductEditorContext m_editorContext = {};

new_editor/app/Host/D3D12WindowRenderLoop.cpp

@@ -52,12 +52,7 @@ bool RenderD3D12WindowFrame(
         renderTargetView,
         ::XCEngine::RHI::ResourceStates::RenderTarget,
         ::XCEngine::RHI::ResourceStates::Present);
-    renderContext.commandList->Close();
-
-    void* commandLists[] = { renderContext.commandList };
-    renderContext.commandQueue->ExecuteCommandLists(1, commandLists);
-    windowRenderer.GetSwapChain()->Present(1, 0);
-    return true;
+    return windowRenderer.SubmitFrame(true);
 }
 
 } // namespace XCEngine::UI::Editor::Host

new_editor/app/Host/D3D12WindowRenderer.cpp

@@ -174,6 +174,24 @@ bool D3D12WindowRenderer::BeginFrame() {
     return true;
 }
 
+bool D3D12WindowRenderer::SubmitFrame(bool presentSwapChain) {
+    if (m_commandList == nullptr || m_commandQueue == nullptr) {
+        return false;
+    }
+
+    if (presentSwapChain && m_swapChain == nullptr) {
+        return false;
+    }
+
+    m_commandList->Close();
+    void* commandLists[] = { m_commandList };
+    m_commandQueue->ExecuteCommandLists(1, commandLists);
+    if (presentSwapChain) {
+        m_swapChain->Present(1, 0);
+    }
+    return true;
+}
+
 ID3D12Device* D3D12WindowRenderer::GetDevice() const {
     const D3D12Device* device = GetD3D12Device();
     return device != nullptr ? device->GetDevice() : nullptr;

new_editor/app/Host/D3D12WindowRenderer.h

@@ -36,6 +36,7 @@ public:
     void Shutdown();
     void Resize(int width, int height);
     bool BeginFrame();
+    bool SubmitFrame(bool presentSwapChain);
 
     ID3D12Device* GetDevice() const;
     ID3D12DescriptorHeap* GetSrvHeap() const;

new_editor/app/Workspace/ProductEditorWorkspace.cpp

@@ -138,6 +138,18 @@ void ProductEditorWorkspace::Initialize(
     m_projectPanel.Initialize(repoRoot);
 }
 
+void ProductEditorWorkspace::AttachViewportWindowRenderer(Host::D3D12WindowRenderer& renderer) {
+    m_viewportHostService.AttachWindowRenderer(renderer);
+}
+
+void ProductEditorWorkspace::DetachViewportWindowRenderer() {
+    m_viewportHostService.DetachWindowRenderer();
+}
+
+void ProductEditorWorkspace::SetViewportSurfacePresentationEnabled(bool enabled) {
+    m_viewportHostService.SetSurfacePresentationEnabled(enabled);
+}
+
 void ProductEditorWorkspace::Shutdown() {
     m_shellFrame = {};
     m_shellInteractionState = {};
@@ -206,6 +218,11 @@ void ProductEditorWorkspace::Update(
         m_shellFrame.workspaceInteractionFrame.composeFrame.contentHostFrame);
 }
 
+void ProductEditorWorkspace::RenderRequestedViewports(
+    const ::XCEngine::Rendering::RenderContext& renderContext) {
+    m_viewportHostService.RenderRequestedViewports(renderContext);
+}
+
 void ProductEditorWorkspace::Append(UIDrawList& drawList) const {
     const auto& metrics = ResolveUIEditorShellInteractionMetrics();
     const auto& palette = ResolveUIEditorShellInteractionPalette();

new_editor/app/Workspace/ProductEditorWorkspace.h

@@ -9,10 +9,12 @@
 #include "Viewport/ProductViewportHostService.h"
 #include "Workspace/ProductEditorWorkspaceEventRouter.h"
 
+#include <Host/D3D12WindowRenderer.h>
 #include <Host/NativeRenderer.h>
 
 #include <XCEditor/Shell/UIEditorShellInteraction.h>
 
+#include <XCEngine/Rendering/RenderContext.h>
 #include <XCEngine/UI/DrawData.h>
 
 #include <filesystem>
@@ -27,12 +29,17 @@ public:
         const std::filesystem::path& repoRoot,
         Host::NativeRenderer& renderer);
     void Shutdown();
+    void AttachViewportWindowRenderer(Host::D3D12WindowRenderer& renderer);
+    void DetachViewportWindowRenderer();
+    void SetViewportSurfacePresentationEnabled(bool enabled);
 
     void Update(
         ProductEditorContext& context,
         const ::XCEngine::UI::UIRect& bounds,
         const std::vector<::XCEngine::UI::UIInputEvent>& inputEvents,
         std::string_view captureText);
+    void RenderRequestedViewports(
+        const ::XCEngine::Rendering::RenderContext& renderContext);
     void Append(::XCEngine::UI::UIDrawList& drawList) const;
 
     const UIEditorShellInteractionFrame& GetShellFrame() const;