游戏程序设计学习初窥简单DirectX代码实现

#include <d3dx9.h>
#define MAX_LOADSTRING 100

// 全局变量:
HINSTANCE hInst;				                // 当前实例
TCHAR szTitle[MAX_LOADSTRING];					// 标题栏文本
TCHAR szWindowClass[MAX_LOADSTRING];		        	// 主窗口类名
LPDIRECT3D9 g_pD3D = NULL;
LPDIRECT3DDEVICE9 g_pD3DDevice = NULL;
LPDIRECT3DVERTEXBUFFER9 g_pVertexBuffer = NULL; // Buffer to hold vertices

//定义顶点信息的结构体
struct CUSTOMVERTEX
{
FLOAT x, y, z, rhw;		// The transformed position for the vertex.
DWORD colour;			// The vertex colour.
};

//定义自由顶点格式
#define D3DFVF_CUSTOMVERTEX (D3DFVF_XYZRHW|D3DFVF_DIFFUSE)

//定义释放COM对象的宏
#define SafeRelease(pObject) if(pObject != NULL) {pObject->Release(); pObject=NULL;}

// 此代码模块中包含的函数的前向声明:
ATOM				MyRegisterClass(HINSTANCE hInstance);
BOOL				InitInstance(HINSTANCE, int);
LRESULT CALLBACK	WndProc(HWND, UINT, WPARAM, LPARAM);
LRESULT CALLBACK	About(HWND, UINT, WPARAM, LPARAM);

//初始化D3D设备
HRESULT InitialiseD3D(HWND hWnd)
{
//First of all, create the main D3D object. If it is created successfully we
//should get a pointer to an IDirect3D8 interface.
//取得D3D9的对象
g_pD3D = Direct3DCreate9(D3D_SDK_VERSION);
if(g_pD3D == NULL)
{
return E_FAIL;
}

//得到当前的显示模式
//Get the current display mode
D3DDISPLAYMODE d3ddm;
if(FAILED(g_pD3D->GetAdapterDisplayMode(D3DADAPTER_DEFAULT, &d3ddm)))
{
return E_FAIL;
}

//创建一个D3D设备
//Create a structure to hold the settings for our device
D3DPRESENT_PARAMETERS d3dpp;
ZeroMemory(&d3dpp, sizeof(d3dpp));

//Fill the structure.
//We want our program to be windowed, and set the back buffer to a format
//that matches our current display mode
d3dpp.Windowed = TRUE;//全屏模式还是窗口模式
d3dpp.SwapEffect = D3DSWAPEFFECT_DISCARD;//后台缓冲区复制到前台时,清除后台缓冲区内容
d3dpp.BackBufferFormat = d3ddm.Format;//屏幕的显示模式

//创建一个Direct3D设备
//Create a Direct3D device.
if(FAILED(g_pD3D->CreateDevice(D3DADAPTER_DEFAULT, D3DDEVTYPE_HAL, hWnd,
D3DCREATE_SOFTWARE_VERTEXPROCESSING, &d3dpp, &g_pD3DDevice)))
{
return E_FAIL;
}

return S_OK;
}

HRESULT InitialiseVertexBuffer()
{
VOID* pVertices;

//顶点信息数组
//Store each point of the triangle together with it's colour
CUSTOMVERTEX cvVertices[] =
{
{250.0f, 100.0f, 0.5f, 1.0f, D3DCOLOR_XRGB(255, 0, 0),},	//Vertex 1 - Red	(250, 100)
{400.0f, 350.0f, 0.5f, 1.0f, D3DCOLOR_XRGB(0, 255, 0),},	//Vertex 2 - Green	(400, 350)
{100.0f, 350.0f, 0.5f, 1.0f, D3DCOLOR_XRGB(0, 0, 255),},	//Vertex 3 - Blue	(100, 350)
};

//通过设备创建顶点缓冲
//Create the vertex buffer from our device
if(FAILED(g_pD3DDevice->CreateVertexBuffer(3 * sizeof(CUSTOMVERTEX),
0, D3DFVF_CUSTOMVERTEX,
D3DPOOL_DEFAULT, &g_pVertexBuffer,NULL)))
{
return E_FAIL;
}

//锁定顶点缓冲，并得到一个存放顶点信息的缓冲区的指针
//Get a pointer to the vertex buffer vertices and lock the vertex buffer
if(FAILED(g_pVertexBuffer->Lock(0, sizeof(cvVertices), (void**)&pVertices, 0)))
{
return E_FAIL;
}

//复制顶点信息
//Copy our stored vertices values into the vertex buffer
memcpy(pVertices, cvVertices, sizeof(cvVertices));

//解锁顶点缓冲区
//Unlock the vertex buffer
g_pVertexBuffer->Unlock();

return S_OK;
}

void Render()
{
if(g_pD3DDevice == NULL)
{
return;
}

//Clear the backbuffer to black
//清空后备缓冲区为黑色
g_pD3DDevice->Clear(0, NULL, D3DCLEAR_TARGET, D3DCOLOR_XRGB(0, 0, 0), 1.0f, 0);

//Begin the scene
//开始绘制场景
g_pD3DDevice->BeginScene();

//Rendering our triangle
//渲染三角形
g_pD3DDevice->SetStreamSource(0, g_pVertexBuffer, 0, sizeof(CUSTOMVERTEX));
g_pD3DDevice->SetFVF(D3DFVF_CUSTOMVERTEX);
g_pD3DDevice->DrawPrimitive(D3DPT_TRIANGLELIST, 0, 1);

//End the scene
//结束绘制场景
g_pD3DDevice->EndScene();

//Filp the back and front buffers so that whatever has been rendered on the back buffer
//will now be visible on screen (front buffer).
//翻页显示
g_pD3DDevice->Present(NULL, NULL, NULL, NULL);
}

//释放所使用到的所有COM对象
void CleanUp()
{
SafeRelease(g_pVertexBuffer);
SafeRelease(g_pD3DDevice);
SafeRelease(g_pD3D);
}

//游戏循环
void GameLoop()
{
//进入游戏循环
MSG msg;
BOOL fMessage;

PeekMessage(&msg, NULL, 0U, 0U, PM_NOREMOVE);

while(msg.message != WM_QUIT)
{
fMessage = PeekMessage(&msg, NULL, 0U, 0U, PM_REMOVE);

if(fMessage)
{
//处理消息
TranslateMessage(&msg);
DispatchMessage(&msg);
}
else
{
//No message to process, so render the current scene
//如果没有消息，则渲染当前的场景
Render();
}

}
}

int APIENTRY _tWinMain(HINSTANCE hInstance,
HINSTANCE hPrevInstance,
LPTSTR    lpCmdLine,
int       nCmdShow)
{
//Register the window class
//注册Windows的窗口类
WNDCLASSEX wc = {sizeof(WNDCLASSEX), CS_CLASSDC, WndProc, 0L, 0L,
GetModuleHandle(NULL), NULL, NULL, NULL, NULL,
"D3DDrawGraphics", NULL};
RegisterClassEx(&wc);

//Create the application's window
//创建一个窗口
HWND hWnd = CreateWindow("D3DDrawGraphics", "D3D绘制简单图形",
WS_OVERLAPPEDWINDOW, 50, 50, 500, 500,
GetDesktopWindow(), NULL, wc.hInstance, NULL);

//Initialize Direct3D
//初始化Direct3D
if(SUCCEEDED(InitialiseD3D(hWnd)))
{
//Show our window
//显示窗口
ShowWindow(hWnd, SW_SHOWDEFAULT);
UpdateWindow(hWnd);

//Initialize Vertex Buffer
//初始化顶点缓冲
if(SUCCEEDED(InitialiseVertexBuffer()))
{
//Start game running: Enter the game loop
//开始游戏: 进入游戏循环
GameLoop();
}
}

CleanUp();

//撤销窗口类的注册
UnregisterClass("D3DDrawGraphics", wc.hInstance);

return 0;
}

//
//  函数: MyRegisterClass()
//
//  目的: 注册窗口类。
//
//  注释:
//
//    仅当希望在已添加到 Windows 95 的
//    “RegisterClassEx”函数之前此代码与 Win32 系统兼容时，
//    才需要此函数及其用法。调用此函数
//    十分重要，这样应用程序就可以获得关联的
//   “格式正确的”小图标。
//
ATOM MyRegisterClass(HINSTANCE hInstance)
{
WNDCLASSEX wcex;

wcex.cbSize = sizeof(WNDCLASSEX);

wcex.style			= CS_HREDRAW | CS_VREDRAW;
wcex.lpfnWndProc	= (WNDPROC)WndProc;
wcex.cbClsExtra		= 0;
wcex.cbWndExtra		= 0;
wcex.hInstance		= hInstance;
wcex.hIcon			= LoadIcon(hInstance, (LPCTSTR)IDI_MY);
wcex.hCursor		= LoadCursor(NULL, IDC_ARROW);
wcex.hbrBackground	= (HBRUSH)(COLOR_WINDOW+1);
wcex.lpszMenuName	= (LPCTSTR)IDC_MY;
wcex.lpszClassName	= szWindowClass;
wcex.hIconSm		= LoadIcon(wcex.hInstance, (LPCTSTR)IDI_SMALL);

return RegisterClassEx(&wcex);
}

//
//   函数: InitInstance(HANDLE, int)
//
//   目的: 保存实例句柄并创建主窗口
//
//   注释:
//
//        在此函数中，我们在全局变量中保存实例句柄并
//        创建和显示主程序窗口。
//
BOOL InitInstance(HINSTANCE hInstance, int nCmdShow)
{
HWND hWnd;

hInst = hInstance; // 将实例句柄存储在全局变量中

hWnd = CreateWindow(szWindowClass, szTitle, WS_OVERLAPPEDWINDOW,
CW_USEDEFAULT, 0, CW_USEDEFAULT, 0, NULL, NULL, hInstance, NULL);

if (!hWnd)
{
return FALSE;
}

ShowWindow(hWnd, nCmdShow);
UpdateWindow(hWnd);

return TRUE;
}

//
//  函数: WndProc(HWND, unsigned, WORD, LONG)
//
//  目的: 处理主窗口的消息。
//
//  WM_COMMAND	- 处理应用程序菜单
//  WM_PAINT	- 绘制主窗口
//  WM_DESTROY	- 发送退出消息并返回
//
//
LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam)
{
switch(message)
{
case WM_DESTROY:
PostQuitMessage(0);
return 0;
break;
case WM_KEYUP:
switch (wParam)
{
case VK_ESCAPE:
//User has pressed the escape key, so quit
DestroyWindow(hWnd);
return 0;
break;
}
break;

}

return DefWindowProc(hWnd, message, wParam, lParam);
}

// “关于”框的消息处理程序。
LRESULT CALLBACK About(HWND hDlg, UINT message, WPARAM wParam, LPARAM lParam)
{
switch (message)
{
case WM_INITDIALOG:
return TRUE;

case WM_COMMAND:
if (LOWORD(wParam) == IDOK || LOWORD(wParam) == IDCANCEL)
{
EndDialog(hDlg, LOWORD(wParam));
return TRUE;
}
break;
}
return FALSE;
}