Factoring out Win32-specific code from DXSample

In order to run the same code on multiple platforms (e.g. UWP, Xbox),
Win32-specific code needs to be decoupled from the DXSample base class.
This change is the first step in that direction.

+Win32Application class to encapsulate Win32-specific functionality.
*Generic Win32 OnEvent is replaced with specific handlers for messages
the samples currently handle.

Samples/D3D1211On12/src/D3D1211On12.cpp

@@ -40,7 +40,7 @@ void D3D1211on12::LoadPipeline()
 {
 	UINT d3d11DeviceFlags = D3D11_CREATE_DEVICE_BGRA_SUPPORT;
 	D2D1_FACTORY_OPTIONS d2dFactoryOptions = {};
-#ifdef _DEBUG
+#if defined(_DEBUG)
 	// Enable the D2D debug layer.
 	d2dFactoryOptions.debugLevel = D2D1_DEBUG_LEVEL_INFORMATION;
 
@@ -98,7 +98,7 @@ void D3D1211on12::LoadPipeline()
 	swapChainDesc.BufferDesc.Format = DXGI_FORMAT_R8G8B8A8_UNORM;
 	swapChainDesc.BufferUsage = DXGI_USAGE_RENDER_TARGET_OUTPUT;
 	swapChainDesc.SwapEffect = DXGI_SWAP_EFFECT_FLIP_DISCARD;
-	swapChainDesc.OutputWindow = m_hwnd;
+	swapChainDesc.OutputWindow = Win32Application::GetHwnd();
 	swapChainDesc.SampleDesc.Count = 1;
 	swapChainDesc.Windowed = TRUE;
 
@@ -112,7 +112,7 @@ void D3D1211on12::LoadPipeline()
 	ThrowIfFailed(swapChain.As(&m_swapChain));
 
 	// This sample does not support fullscreen transitions.
-	ThrowIfFailed(factory->MakeWindowAssociation(m_hwnd, DXGI_MWA_NO_ALT_ENTER));
+	ThrowIfFailed(factory->MakeWindowAssociation(Win32Application::GetHwnd(), DXGI_MWA_NO_ALT_ENTER));
 
 	m_frameIndex = m_swapChain->GetCurrentBackBufferIndex();
 
@@ -230,7 +230,7 @@ void D3D1211on12::LoadAssets()
 		ComPtr<ID3DBlob> vertexShader;
 		ComPtr<ID3DBlob> pixelShader;
 
-#ifdef _DEBUG
+#if defined(_DEBUG)
 		// Enable better shader debugging with the graphics debugging tools.
 		UINT compileFlags = D3DCOMPILE_DEBUG | D3DCOMPILE_SKIP_OPTIMIZATION;
 #else
@@ -374,7 +374,7 @@ void D3D1211on12::OnRender()
 	RenderUI();
 
 	// Present the frame.
-	ThrowIfFailed(m_swapChain->Present(0, 0));
+	ThrowIfFailed(m_swapChain->Present(1, 0));
 
 	MoveToNextFrame();
 }
@@ -419,11 +419,6 @@ void D3D1211on12::OnDestroy()
 	CloseHandle(m_fenceEvent);
 }
 
-bool D3D1211on12::OnEvent(MSG)
-{
-	return false;
-}
-
 void D3D1211on12::PopulateCommandList()
 {
 	// Command list allocators can only be reset when the associated 

Samples/D3D1211On12/src/D3D1211On12.h

@@ -21,12 +21,10 @@ class D3D1211on12 : public DXSample
 public:
 	D3D1211on12(UINT width, UINT height, std::wstring name);
 
-protected:
 	virtual void OnInit();
 	virtual void OnUpdate();
 	virtual void OnRender();
 	virtual void OnDestroy();
-	virtual bool OnEvent(MSG msg);
 
 private:
 	static const UINT FrameCount = 3;

Samples/D3D1211On12/src/D3D1211On12.vcxproj

@@ -96,13 +96,15 @@
     </CustomBuild>
   </ItemGroup>
   <ItemGroup>
+    <ClInclude Include="Win32Application.h" />
     <ClInclude Include="D3D1211On12.h" />
     <ClInclude Include="d3dx12.h" />
     <ClInclude Include="DXSample.h" />
     <ClInclude Include="DXSampleHelper.h" />
     <ClInclude Include="stdafx.h" />
   </ItemGroup>
   <ItemGroup>
+    <ClCompile Include="Win32Application.cpp" />
     <ClCompile Include="D3D1211On12.cpp" />
     <ClCompile Include="DXSample.cpp" />
     <ClCompile Include="Main.cpp" />

Samples/D3D1211On12/src/D3D1211On12.vcxproj.filters

@@ -44,6 +44,9 @@
     <ClInclude Include="stdafx.h">
       <Filter>Header Files</Filter>
     </ClInclude>
+    <ClInclude Include="Win32Application.h">
+      <Filter>Header Files\Util</Filter>
+    </ClInclude>
   </ItemGroup>
   <ItemGroup>
     <ClCompile Include="D3D1211On12.cpp">
@@ -58,5 +61,8 @@
     <ClCompile Include="stdafx.cpp">
       <Filter>Source Files</Filter>
     </ClCompile>
+    <ClCompile Include="Win32Application.cpp">
+      <Filter>Source Files\Util</Filter>
+    </ClCompile>
   </ItemGroup>
 </Project>

Samples/D3D1211On12/src/DXSample.cpp

@@ -11,17 +11,13 @@
 
 #include "stdafx.h"
 #include "DXSample.h"
-#include <shellapi.h>
 
 DXSample::DXSample(UINT width, UINT height, std::wstring name) :
 	m_width(width),
 	m_height(height),
+	m_title(name),
 	m_useWarpDevice(false)
 {
-	ParseCommandLineArgs();
-
-	m_title = name + (m_useWarpDevice ? L" (WARP)" : L"");
-
 	WCHAR assetsPath[512];
 	GetAssetsPath(assetsPath, _countof(assetsPath));
 	m_assetsPath = assetsPath;
@@ -33,67 +29,6 @@ DXSample::~DXSample()
 {
 }
 
-int DXSample::Run(HINSTANCE hInstance, int nCmdShow)
-{
-	// Initialize the window class.
-	WNDCLASSEX windowClass = { 0 };
-	windowClass.cbSize = sizeof(WNDCLASSEX);
-	windowClass.style = CS_HREDRAW | CS_VREDRAW;
-	windowClass.lpfnWndProc = WindowProc;
-	windowClass.hInstance = hInstance;
-	windowClass.hCursor = LoadCursor(NULL, IDC_ARROW);
-	windowClass.lpszClassName = L"WindowClass1";
-	RegisterClassEx(&windowClass);
-
-	RECT windowRect = { 0, 0, static_cast<LONG>(m_width), static_cast<LONG>(m_height) };
-	AdjustWindowRect(&windowRect, WS_OVERLAPPEDWINDOW, FALSE);
-
-	// Create the window and store a handle to it.
-	m_hwnd = CreateWindowEx(NULL,
-		L"WindowClass1",
-		m_title.c_str(),
-		WS_OVERLAPPEDWINDOW,
-		300,
-		300,
-		windowRect.right - windowRect.left,
-		windowRect.bottom - windowRect.top,
-		NULL,		// We have no parent window, NULL.
-		NULL,		// We aren't using menus, NULL.
-		hInstance,
-		NULL);		// We aren't using multiple windows, NULL.
-
-	ShowWindow(m_hwnd, nCmdShow);
-
-	// Initialize the sample. OnInit is defined in each child-implementation of DXSample.
-	OnInit();
-
-	// Main sample loop.
-	MSG msg = { 0 };
-	while (true)
-	{
-		// Process any messages in the queue.
-		if (PeekMessage(&msg, NULL, 0, 0, PM_REMOVE))
-		{
-			TranslateMessage(&msg);
-			DispatchMessage(&msg);
-
-			if (msg.message == WM_QUIT)
-				break;
-
-			// Pass events into our sample.
-			OnEvent(msg);
-		}
-
-		OnUpdate();
-		OnRender();
-	}
-
-	OnDestroy();
-
-	// Return this part of the WM_QUIT message to Windows.
-	return static_cast<char>(msg.wParam);
-}
-
 // Helper function for resolving the full path of assets.
 std::wstring DXSample::GetAssetFullPath(LPCWSTR assetName)
 {
@@ -102,7 +37,8 @@ std::wstring DXSample::GetAssetFullPath(LPCWSTR assetName)
 
 // Helper function for acquiring the first available hardware adapter that supports Direct3D 12.
 // If no such adapter can be found, *ppAdapter will be set to nullptr.
-void DXSample::GetHardwareAdapter(_In_ IDXGIFactory4* pFactory, _Outptr_result_maybenull_ IDXGIAdapter1** ppAdapter)
+_Use_decl_annotations_
+void DXSample::GetHardwareAdapter(IDXGIFactory2* pFactory, IDXGIAdapter1** ppAdapter)
 {
 	IDXGIAdapter1* pAdapter = nullptr;
 	*ppAdapter = nullptr;
@@ -134,36 +70,20 @@ void DXSample::GetHardwareAdapter(_In_ IDXGIFactory4* pFactory, _Outptr_result_m
 void DXSample::SetCustomWindowText(LPCWSTR text)
 {
 	std::wstring windowText = m_title + L": " + text;
-	SetWindowText(m_hwnd, windowText.c_str());
+	SetWindowText(Win32Application::GetHwnd(), windowText.c_str());
 }
 
 // Helper function for parsing any supplied command line args.
-void DXSample::ParseCommandLineArgs()
+_Use_decl_annotations_
+void DXSample::ParseCommandLineArgs(WCHAR* argv[], int argc)
 {
-	int argc;
-	LPWSTR *argv = CommandLineToArgvW(GetCommandLineW(), &argc);
 	for (int i = 1; i < argc; ++i)
 	{
 		if (_wcsnicmp(argv[i], L"-warp", wcslen(argv[i])) == 0 || 
 			_wcsnicmp(argv[i], L"/warp", wcslen(argv[i])) == 0)
 		{
 			m_useWarpDevice = true;
+			m_title = m_title + L" (WARP)";
 		}
 	}
-	LocalFree(argv);
-}
-
-// Main message handler for the sample.
-LRESULT CALLBACK DXSample::WindowProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam)
-{
-	// Handle destroy/shutdown messages.
-	switch (message)
-	{
-	case WM_DESTROY:
-		PostQuitMessage(0);
-		return 0;
-	}
-
-	// Handle any messages the switch statement didn't.
-	return DefWindowProc(hWnd, message, wParam, lParam);
 }

Samples/D3D1211On12/src/DXSample.h

@@ -12,42 +12,44 @@
 #pragma once
 
 #include "DXSampleHelper.h"
+#include "Win32Application.h"
 
 class DXSample
 {
 public:
 	DXSample(UINT width, UINT height, std::wstring name);
 	virtual ~DXSample();
 
-	int Run(HINSTANCE hInstance, int nCmdShow);
-	void SetCustomWindowText(LPCWSTR text);
-
-protected:
 	virtual void OnInit() = 0;
 	virtual void OnUpdate() = 0;
 	virtual void OnRender() = 0;
 	virtual void OnDestroy() = 0;
-	virtual bool OnEvent(MSG msg) = 0;
 
-	std::wstring GetAssetFullPath(LPCWSTR assetName);
-	void GetHardwareAdapter(_In_ IDXGIFactory4* pFactory, _Outptr_result_maybenull_ IDXGIAdapter1** ppAdapter);
+	// Samples override the event handlers to handle specific messages.
+	virtual void OnKeyDown(UINT8 /*key*/)   {}
+	virtual void OnKeyUp(UINT8 /*key*/)     {}
+
+	// Accessors.
+	UINT GetWidth() const           { return m_width; }
+	UINT GetHeight() const          { return m_height; }
+	const WCHAR* GetTitle() const   { return m_title.c_str(); }
 
-	static LRESULT CALLBACK WindowProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam);
+	void ParseCommandLineArgs(_In_reads_(argc) WCHAR* argv[], int argc);
+
+protected:
+	std::wstring GetAssetFullPath(LPCWSTR assetName);
+	void GetHardwareAdapter(_In_ IDXGIFactory2* pFactory, _Outptr_result_maybenull_ IDXGIAdapter1** ppAdapter);
+	void SetCustomWindowText(LPCWSTR text);
 
 	// Viewport dimensions.
 	UINT m_width;
 	UINT m_height;
 	float m_aspectRatio;
 
-	// Window handle.
-	HWND m_hwnd;
-
 	// Adapter info.
 	bool m_useWarpDevice;
 
 private:
-	void ParseCommandLineArgs();
-
 	// Root assets path.
 	std::wstring m_assetsPath;
 

Samples/D3D1211On12/src/Main.cpp

@@ -16,5 +16,5 @@ _Use_decl_annotations_
 int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE, LPSTR, int nCmdShow)
 {
 	D3D1211on12 sample(1280, 720, L"D3D12 11 on 12 Sample");
-	return sample.Run(hInstance, nCmdShow);
+	return Win32Application::Run(&sample, hInstance, nCmdShow);
 }