Add WinUI3 Support (#1208)

- Update bgfx with [PR that adds support for
WinUI3](bkaradzic/bgfx#3044).
- Modify WinRT/UWP window contract to take an IInspectable to avoid
C++/WinRT versioning issues.
- Add some custom code generation for Windows App SDK for ABI-stable
headers also to avoid C++/WinRT versioning issues.
- Minor fixes in TestUtils for WinRT for consistency.

Author: bghgary

Apps/Playground/UWP/App.cpp

@@ -10,11 +10,25 @@
 #include <Babylon/Polyfills/XMLHttpRequest.h>
 #include <Babylon/Polyfills/Canvas.h>
 
-#include <pplawait.h>
-#include <winrt/Windows.ApplicationModel.h>
-
 #include <winrt/windows.ui.core.h>
 
+namespace
+{
+    template <typename T>
+    T from_cx(Platform::Object^ from)
+    {
+        T to{ nullptr };
+
+        if (from != nullptr)
+        {
+            winrt::check_hresult(reinterpret_cast<::IUnknown*>(from)
+                ->QueryInterface(winrt::guid_of<T>(), winrt::put_abi(to)));
+        }
+
+        return to;
+    }
+}
+
 using namespace Windows::ApplicationModel;
 using namespace Windows::ApplicationModel::Core;
 using namespace Windows::ApplicationModel::Activation;
@@ -348,7 +362,7 @@ void App::RestartRuntime(Windows::Foundation::Rect bounds)
     m_displayScale = static_cast<float>(displayInformation->RawPixelsPerViewPixel);
     size_t width = static_cast<size_t>(bounds.Width * m_displayScale);
     size_t height = static_cast<size_t>(bounds.Height * m_displayScale);
-    auto* window = reinterpret_cast<winrt::Windows::UI::Core::ICoreWindow*>(CoreWindow::GetForCurrentThread());
+    auto window = from_cx<winrt::Windows::Foundation::IInspectable>(CoreWindow::GetForCurrentThread());
 
     Babylon::Graphics::WindowConfiguration graphicsConfig{};
     graphicsConfig.Window = window;

Apps/ValidationTests/UWP/App.cpp

@@ -11,11 +11,25 @@
 #include <Babylon/Polyfills/Canvas.h>
 #include <Babylon/Polyfills/XMLHttpRequest.h>
 
-#include <pplawait.h>
-#include <winrt/Windows.ApplicationModel.h>
-
 #include <winrt/windows.ui.core.h>
 
+namespace
+{
+    template <typename T>
+    T from_cx(Platform::Object^ from)
+    {
+        T to{ nullptr };
+
+        if (from != nullptr)
+        {
+            winrt::check_hresult(reinterpret_cast<::IUnknown*>(from)
+                ->QueryInterface(winrt::guid_of<T>(), winrt::put_abi(to)));
+        }
+
+        return to;
+    }
+}
+
 using namespace Windows::ApplicationModel;
 using namespace Windows::ApplicationModel::Core;
 using namespace Windows::ApplicationModel::Activation;
@@ -192,7 +206,7 @@ void App::RestartRuntime(Windows::Foundation::Rect bounds)
     m_displayScale = static_cast<float>(displayInformation->RawPixelsPerViewPixel);
     size_t width = static_cast<size_t>(bounds.Width * m_displayScale);
     size_t height = static_cast<size_t>(bounds.Height * m_displayScale);
-    auto* window = reinterpret_cast<winrt::Windows::UI::Core::ICoreWindow*>(CoreWindow::GetForCurrentThread());
+    auto window = from_cx<winrt::Windows::Foundation::IInspectable>(CoreWindow::GetForCurrentThread());
 
     Babylon::Graphics::WindowConfiguration graphicsConfig{};
     graphicsConfig.Window = window;

CMakeLists.txt

@@ -37,7 +37,7 @@ option(BABYLON_NATIVE_POLYFILL_CANVAS "Include Babylon Native Polyfill Canvas."
 
 if(APPLE)
     # without this option on azure pipelines, there is a mismatch with math.h giving a lot of undefined functions on macOS.
-    # only enabled for Apple as there is no issue for UWP/WIN32
+    # only enabled for Apple as there is no issue for Windows
     set(CMAKE_NO_SYSTEM_FROM_IMPORTED TRUE)
 endif()
 
@@ -49,7 +49,7 @@ elseif(IOS)
 elseif(APPLE)
     set(BABYLON_NATIVE_PLATFORM "macOS")
 elseif(WINDOWS_STORE)
-    set(BABYLON_NATIVE_PLATFORM "UWP")
+    set(BABYLON_NATIVE_PLATFORM "WinRT")
 elseif(WIN32)
     set(BABYLON_NATIVE_PLATFORM "Win32")
 elseif(UNIX)

Core/AppRuntime/Source/AppRuntime_UWP.cpp renamed to Core/AppRuntime/Source/AppRuntime_WinRT.cpp

@@ -1,20 +1,5 @@
-cmake_dependent_option(BABYLON_NATIVE_USE_SWAPCHAINPANEL "Use swap chain panel." OFF WINDOWS_STORE OFF)
-
-if(WINDOWS_STORE)
-    if(BABYLON_NATIVE_USE_SWAPCHAINPANEL)
-        set(PLATFORM_NAME ${BABYLON_NATIVE_PLATFORM}_SwapChainPanel)
-        set(PLATFORM_PATH ${BABYLON_NATIVE_PLATFORM}/SwapChainPanel)
-    else()
-        set(PLATFORM_NAME ${BABYLON_NATIVE_PLATFORM}_CoreWindow)
-        set(PLATFORM_PATH ${BABYLON_NATIVE_PLATFORM}/CoreWindow)
-    endif()
-else()
-    set(PLATFORM_NAME ${BABYLON_NATIVE_PLATFORM})
-    set(PLATFORM_PATH ${BABYLON_NATIVE_PLATFORM})
-endif()
-
 set(SOURCES
-    "Include/Platform/${PLATFORM_PATH}/Babylon/Graphics/Platform.h"
+    "Include/Platform/${BABYLON_NATIVE_PLATFORM}/Babylon/Graphics/Platform.h"
     "Include/RendererType/${GRAPHICS_API}/Babylon/Graphics/RendererType.h"
     "Include/Shared/Babylon/Graphics/Device.h"
     "InternalInclude/Babylon/Graphics/BgfxCallback.h"
@@ -29,7 +14,7 @@ set(SOURCES
     "Source/DeviceContext.cpp"
     "Source/DeviceImpl.cpp"
     "Source/DeviceImpl.h"
-    "Source/DeviceImpl_${PLATFORM_NAME}.${BABYLON_NATIVE_PLATFORM_IMPL_EXT}"
+    "Source/DeviceImpl_${BABYLON_NATIVE_PLATFORM}.${BABYLON_NATIVE_PLATFORM_IMPL_EXT}"
     "Source/DeviceImpl_${GRAPHICS_API}.cpp"
     "Source/SafeTimespanGuarantor.cpp"
     "Source/Texture.cpp")
@@ -39,11 +24,14 @@ warnings_as_errors(Graphics)
 
 target_include_directories(Graphics
     PRIVATE "Include/Shared"
-    PRIVATE "Include/Platform/${PLATFORM_PATH}"
+    PRIVATE "Include/Platform/${BABYLON_NATIVE_PLATFORM}"
     PRIVATE "Include/RendererType/${GRAPHICS_API}"
     PRIVATE "InternalInclude/Babylon/Graphics")
 
-if(WIN32 AND NOT WINDOWS_STORE)
+if(WINDOWS_STORE)
+    target_link_to_dependencies(Graphics
+        PRIVATE WindowsAppSDK)
+elseif(WIN32)
     target_link_to_dependencies(Graphics
         PRIVATE "shlwapi.lib")
 elseif(ANDROID)
@@ -78,7 +66,7 @@ endif()
 add_library(GraphicsDevice INTERFACE)
 target_include_directories(GraphicsDevice
     INTERFACE "Include/Shared"
-    INTERFACE "Include/Platform/${PLATFORM_PATH}"
+    INTERFACE "Include/Platform/${BABYLON_NATIVE_PLATFORM}"
     INTERFACE "Include/RendererType/${GRAPHICS_API}")
 target_link_to_dependencies(GraphicsDevice
     INTERFACE Graphics

Core/Graphics/CMakeLists.txt

@@ -1,11 +1,16 @@
 #pragma once
 
-#include <winrt/windows.ui.core.h>
 #include <stdint.h>
+#include <Unknwn.h>
+#include <winrt/base.h>
 
 namespace Babylon::Graphics
 {
-    using WindowType = winrt::Windows::UI::Core::ICoreWindow*;
+    // Supported types:
+    // - Windows::Core::UI::ICoreWindow
+    // - Windows::UI::Xaml::Controls::ISwapChainPanel
+    // - Microsoft::UI::Xaml::Controls::ISwapChainPanel
+    using WindowType = winrt::Windows::Foundation::IInspectable;
 
     struct WindowConfiguration
     {

Core/Graphics/Include/Platform/UWP/SwapChainPanel/Babylon/Graphics/Platform.h

@@ -0,0 +1,39 @@
+#include <Babylon/Graphics/Platform.h>
+#include "DeviceImpl.h"
+#include <Windows.UI.Core.h>
+#include <Windows.UI.Xaml.Controls.h>
+#include <Microsoft.UI.Xaml.Controls.h>
+#include <winrt/Windows.Graphics.Display.h>
+
+namespace Babylon::Graphics
+{
+    const bool DeviceImpl::s_bgfxFlipAfterRender = false;
+
+    void DeviceImpl::ConfigureBgfxPlatformData(const WindowConfiguration& config, bgfx::PlatformData& pd)
+    {
+        // Assume window is a xaml swap chain panel if not a core window.
+        if (!config.Window.try_as<ABI::Windows::UI::Core::ICoreWindow>())
+        {
+            // Set ndt greater than 1 for xaml swap chain panels.
+            // See https://github.com/bkaradzic/bgfx/blob/23edb9c4d90744bf90a89ff9e7308b8ff6517fee/src/dxgi.cpp#L531-L552
+            pd.ndt = reinterpret_cast<void*>(2);
+        }
+
+        pd.nwh = winrt::get_abi(config.Window);
+    }
+
+    float DeviceImpl::GetDevicePixelRatio(const WindowConfiguration& config)
+    {
+        if (auto uiElement = config.Window.try_as<ABI::Microsoft::UI::Xaml::IUIElement>())
+        {
+            // Use the ABI layer manually generated from the Windows App SDK winmd files to avoid C++/WinRT versioning issues.
+            DOUBLE rasterizationScale{1};
+            winrt::check_hresult(uiElement->get_RasterizationScale(&rasterizationScale));
+            return static_cast<float>(rasterizationScale);
+        }
+        else
+        {
+            return static_cast<float>(winrt::Windows::Graphics::Display::DisplayInformation::GetForCurrentView().RawPixelsPerViewPixel());
+        }
+    }
+}