利用灵活顶点格式 绘制一个三角形

//////////////////////////////////////////////////////////////////////////
//利用灵活顶点格式 绘制一个三角形
#include <d3d9.h>
#include <d3dx9.h>
#include <Windows.h>

#pragma comment(lib,"d3d9.lib")
#pragma comment(lib,"d3dx9.lib")
#pragma comment(lib,"winmm.lib")

//定义全局变量
LPDIRECT3D9				g_pD3D = NULL;
LPDIRECT3DDEVICE9		g_Pd3dDevice = NULL;

//定义顶点缓存
LPDIRECT3DVERTEXBUFFER9	g_pVB	= NULL;

//自定义顶点类型
struct CUSTOMVERTEX
{
	float x,y,z,rhw;		//rhw: RHW表示投影空间中顶点所在的齐次点(x,y,z,w)(homogeneous point)的w坐标的倒数(reciprocal)
	DWORD color;			//顶点颜色
};

//定义灵活顶点格式的定点结构
#define D3DFVF_CUSTOMVERTEX		(D3DFVF_XYZRHW | D3DFVF_DIFFUSE )	//包含位置属性 和 漫反射颜色属性

//初始化d3d

HRESULT InitD3D( HWND hwnd )
{
	//获得d3d接口指针
	g_pD3D = Direct3DCreate9(D3D_SDK_VERSION);
	if ( !g_pD3D )
	{
		return E_FAIL;
	}

	//填充设备参数
	D3DPRESENT_PARAMETERS	d3dpp;
	ZeroMemory(&d3dpp,sizeof(d3dpp));
	d3dpp.Windowed = TRUE;
	d3dpp.SwapEffect = D3DSWAPEFFECT_DISCARD;
	d3dpp.BackBufferFormat = D3DFMT_X8R8G8B8;
	
	//创建d3d设备
	if( FAILED(g_pD3D->CreateDevice(D3DADAPTER_DEFAULT,D3DDEVTYPE_HAL,hwnd,
						D3DCREATE_HARDWARE_VERTEXPROCESSING,&d3dpp,&g_Pd3dDevice)))
	{
		return E_FAIL;
	}

	return S_OK;
}

//////////////////////////////////////////////////////////////////////////
//初始化顶点缓存
HRESULT InitVB()
{

	//初始化三角形的三个顶点
	CUSTOMVERTEX	Vertexs[] =
	{
		{ 150.0f,  50.0f, 0.5f, 1.0f, 0xffff0000, }, // x, y, z, rhw, color
		{ 250.0f, 250.0f, 0.5f, 1.0f, 0xff00ff00, },
		{  50.0f, 250.0f, 0.5f, 1.0f, 0xff00ffff, }
	};

	//创建顶点缓存
	if( FAILED (g_Pd3dDevice->CreateVertexBuffer(
				3* sizeof(CUSTOMVERTEX),	//为缓存分配的字节数
			    0,		//指定关于如何使用缓存的附加属性
				D3DFVF_CUSTOMVERTEX,	//存储在顶点缓存中顶点的灵活定点格式
				D3DPOOL_DEFAULT,		//容纳缓存的内存池
				&g_pVB,					//传出参数，接受所创建的顶点缓存指针
				NULL
				)))
	{
		return S_FALSE;
	}

	//填充定点缓存
	VOID * pVertices = NULL;		//定义指向缓存内部的指针
	//通过锁住缓存获得pVertices 指针
	if ( g_pVB->Lock(
		0,					//自缓存起始点到开始锁定位置的偏移量,这里表示锁定整个缓存
		sizeof(Vertexs),	//要锁定缓存的大小
		(VOID **)&pVertices,	//指向被锁定缓存起始位置的指针(传出参数)
		0					//锁定标记
		))
	{
		return S_FALSE;
	}
	//顶点信息拷贝到定点缓存中
	memcpy(pVertices,Vertexs,sizeof(Vertexs));
	g_pVB->Unlock();		//操作结束

	return S_OK;
}

//释放资源
void CleanUp()
{
	if (g_pVB )
	{
		g_pVB->Release();
	}
	if (g_Pd3dDevice )
	{
		g_Pd3dDevice->Release();
	}
	if (g_pD3D )
	{
		g_pD3D->Release();
	}
}

//////////////////////////////////////////////////////////////////////////

//渲染函数
void Render(void)
{
	//将屏幕清空为蓝色
	g_Pd3dDevice->Clear(0,NULL,D3DCLEAR_TARGET,D3DCOLOR_XRGB(0,0,255),1.0f,0);

	if (SUCCEEDED (g_Pd3dDevice->BeginScene()))
	{
		//指定数据量输入源
		g_Pd3dDevice->SetStreamSource(0,g_pVB,0,sizeof( CUSTOMVERTEX ));	//最后一个参数是每个顶点的大小
		//设置定点格式
		g_Pd3dDevice->SetFVF(D3DFVF_CUSTOMVERTEX);
		//进行绘制
		g_Pd3dDevice->DrawPrimitive(
			D3DPT_TRIANGLELIST,   //绘制图元的类型
			0,					//顶点数据流中标识顶点数据读取起点的元素的索引
			1					//绘制图元的个数
			);

		g_Pd3dDevice->EndScene();
	}
	//将后台缓冲输出到屏幕
	g_Pd3dDevice->Present(0,0,0,0);
}


//////////////////////////////////////////////////////////////////////////

//消息处理函数

LRESULT WINAPI MgsProc(HWND hwnd,UINT msg,WPARAM wParam,LPARAM lParam )
{
	switch( msg )
	{
	case WM_DESTROY:
		{
			CleanUp();
			PostQuitMessage(0);
			return 0;
		}
	}

	return DefWindowProc(hwnd,msg,wParam,lParam);

}

//WinMain
INT WINAPI WinMain(HINSTANCE hInst,HINSTANCE hInstPre,LPSTR lpcmdLine,INT nShow)
{
	WNDCLASSEX wc =
	{
		sizeof( WNDCLASSEX ), CS_CLASSDC, MgsProc, 0L, 0L,
		GetModuleHandle( NULL ), NULL, NULL, NULL, NULL,
		"D3D Tutorial", NULL
	};
	RegisterClassEx( &wc );

	// Create the application's window
	HWND hWnd = CreateWindow( "D3D Tutorial", "D3D Tutorial 02: Vertices",
		WS_OVERLAPPEDWINDOW, 100, 100, 300, 300,
		NULL, NULL, wc.hInstance, NULL );

	//初始化d3d
	if(SUCCEEDED(InitD3D(hWnd)))
	{
		//创建定点缓存
		if(SUCCEEDED(InitVB()))
		{
			//显示窗口
			ShowWindow(hWnd,SW_SHOWDEFAULT);
			UpdateWindow(hWnd);

			//消息循环
			MSG msg;
			ZeroMemory(&msg,sizeof(msg));

			while(msg.message != WM_QUIT )
			{
				if (PeekMessage(&msg,NULL,0,0,PM_REMOVE))
				{
					TranslateMessage( &msg );
					DispatchMessage( &msg );
				}
				else
				{
						Render();
				}
			}
		}
	}

	UnregisterClass("D3D Tutorial", wc.hInstance );
	return 0;
}