DirectX 9.0 C++ 教程 绘制三角形

注:开发环境设定参考 上篇文章 DirectX 9.0 C++ 教程 开发环境设定

也可以参考下这篇Android Opengl ES下绘制三角形

本例子效果图(来源 DirectX 9.0 SDK):

1.定义一个自定义的顶点(Vertex)类型

// A structure for our custom vertex type
struct CUSTOMVERTEX
{
    FLOAT x, y, z, rhw; // The transformed position for the vertex
    DWORD color;        // The vertex color
};
//这里加入了颜色,后面设计到纹理(Texture)时,还可以加入纹理属性
struct CUSTOMVERTEX
{
   FLOAT x,y,z,rhw;
   DWORD color;
   FLOAT u,v;  //texture coordinate
}

2. 设置顶点缓存(Setting Up the Vertex Buffer)

    // 初始化三个顶点
    CUSTOMVERTEX Vertices[] =
    {
        { 150.0f,  50.0f, 0.5f, 1.0f, D3DCOLOR_XRGB(255,0,0), }, // x, y, z, rhw, color //颜色为蓝色
        { 250.0f, 250.0f, 0.5f, 1.0f, D3DCOLOR_XRGB(0,255,0), },//颜色为绿色
        {  50.0f, 250.0f, 0.5f, 1.0f, D3DCOLOR_XRGB(0,0,255), },//颜色为蓝色
    };
    LPDIRECT3DVERTEXBUFFER9 g_pVB = NULL; // Buffer to hold Vertices
    // 创建顶点缓存
   #define D3DFVF_CUSTOMVERTEX (D3DFVF_XYZRHW|D3DFVF_DIFFUSE)
   if( FAILED( g_pd3dDevice->CreateVertexBuffer( 3*sizeof(CUSTOMVERTEX), //空间大小,3个点故乘以3
                                                  0, D3DFVF_CUSTOMVERTEX,
                                                  D3DPOOL_DEFAULT, &g_pVB, NULL ) ) )
    {
        return E_FAIL;
    }

    // 先锁定需要的内存块,再复制数据
    VOID* pVertices;
    if( FAILED( g_pVB->Lock( 0, sizeof(Vertices), (void**)&pVertices, 0 ) ) )
        return E_FAIL;
    memcpy( pVertices, Vertices, sizeof(Vertices) );
    g_pVB->Unlock();

3.绘制三角形(Rendering the Display)

    // Clear the backbuffer to a blue color
    g_pd3dDevice->Clear( 0, NULL, D3DCLEAR_TARGET, D3DCOLOR_XRGB(0,0,255), 1.0f, 0 );

    // Begin the scene
    if( SUCCEEDED( g_pd3dDevice->BeginScene() ) )
    {
        //Binds a vertex buffer to a device data stream
        g_pd3dDevice->SetStreamSource( 0, g_pVB, 0, sizeof(CUSTOMVERTEX) );
        g_pd3dDevice->SetFVF( D3DFVF_CUSTOMVERTEX );//FVF 指flexible vertex format
        g_pd3dDevice->DrawPrimitive( D3DPT_TRIANGLELIST, 0, 1 ); //D3DPT_TRIANGLELIST表示三角形
        // End the scene
        g_pd3dDevice->EndScene();
    }
    // Present the backbuffer contents to the display
    g_pd3dDevice->Present( NULL, NULL, NULL, NULL );

4.上面设计到的一些函数解释

//CreateVertexBuffer 函数原型
HRESULT CreateVertexBuffer(
UINT Length, //长度,size of vertex buffer
DWORD Usage, //未使用D3DUSAGE_DYNAMIC,则为静态缓存,地形或城市建筑适合
DWORD FVF, //这里用了D3DFVF_XYZRHW和D3DFVF_DIFFUSE,因为顶点定义包含了rhw和颜色
D3DPOOL Pool,//D3DPOOL_DEFAULT
IDirect3DVertexBuffer9** ppVertexBuffer,
HANDLE* pSharedHandle//保留参数,未使用,设置为NULL);

//DrawPrimitive 函数原型
HRESULT DrawPrimitive(
D3DPRIMITIVETYPE PrimitiveType,// D3DPT_POINTLIST点,LINELIST线,D3DPT_TRIANGLELIST三角形 等
UINT StartVertex, //index of first vertex to load
UINT PrimitiveCount //数量
);

5.全部源码

//-----------------------------------------------------------------------------
// File: Vertices.cpp
//
// Desc: In this tutorial, we are rendering some Vertices. This introduces the
//       concept of the vertex buffer, a Direct3D object used to store
//       Vertices. Vertices can be defined any way we want by defining a
//       custom structure and a custom FVF (flexible vertex format). In this
//       tutorial, we are using Vertices that are transformed (meaning they
//       are already in 2D window coordinates) and lit (meaning we are not
//       using Direct3D lighting, but are supplying our own colors).
//
// Copyright (c) Microsoft Corporation. All rights reserved.
//-----------------------------------------------------------------------------
#include <d3d9.h>
#include <strsafe.h>

//-----------------------------------------------------------------------------
// Global variables
//-----------------------------------------------------------------------------
LPDIRECT3D9             g_pD3D       = NULL; // Used to create the D3DDevice
LPDIRECT3DDEVICE9       g_pd3dDevice = NULL; // Our rendering device
LPDIRECT3DVERTEXBUFFER9 g_pVB        = NULL; // Buffer to hold Vertices

// 三角形顶点 结构体
struct CUSTOMVERTEX
{
    FLOAT x, y, z, rhw; // The transformed position for the vertex
    DWORD color;        // The vertex color
};

// Our custom FVF, which describes our custom vertex structure
#define D3DFVF_CUSTOMVERTEX (D3DFVF_XYZRHW|D3DFVF_DIFFUSE)

//-----------------------------------------------------------------------------
// Name: InitD3D()
// Desc: Initializes Direct3D
//-----------------------------------------------------------------------------
HRESULT InitD3D( HWND hWnd )
{
    // Create the D3D object.
    if( NULL == ( g_pD3D = Direct3DCreate9( D3D_SDK_VERSION ) ) )
        return E_FAIL;

    // 初始化 D3DPRESENT_PARAMETERS 结构体
    D3DPRESENT_PARAMETERS d3dpp;
    ZeroMemory( &d3dpp, sizeof(d3dpp) );
    d3dpp.Windowed = TRUE;
    d3dpp.SwapEffect = D3DSWAPEFFECT_DISCARD;
    d3dpp.BackBufferFormat = D3DFMT_UNKNOWN;

    // 创建 D3DDevice
    if( FAILED( g_pD3D->CreateDevice( D3DADAPTER_DEFAULT, D3DDEVTYPE_HAL, hWnd,
                                      D3DCREATE_SOFTWARE_VERTEXPROCESSING,
                                      &d3dpp, &g_pd3dDevice ) ) )
    {
        return E_FAIL;
    }

    // Device state would normally be set here

    return S_OK;
}

//-----------------------------------------------------------------------------
// Name: InitVB()
// Desc: Creates a vertex buffer and fills it with our Vertices. The vertex
//       buffer is basically just a chuck of memory that holds Vertices. After
//       creating it, we must Lock()/Unlock() it to fill it. For indices, D3D
//       also uses index buffers. The special thing about vertex and index
//       buffers is that they can be created in device memory, allowing some
//       cards to process them in hardware, resulting in a dramatic
//       performance gain.
//-----------------------------------------------------------------------------
HRESULT InitVB()
{
    // 初始化三角形的三个顶点坐标
    CUSTOMVERTEX Vertices[] =
    {
        { 150.0f,  50.0f, 0.5f, 1.0f, D3DCOLOR_XRGB(255,0,0), }, // x, y, z, rhw, color
        { 250.0f, 250.0f, 0.5f, 1.0f, D3DCOLOR_XRGB(0,255,0), },
        {  50.0f, 250.0f, 0.5f, 1.0f, D3DCOLOR_XRGB(0,0,255), },
    };

    // 创建 顶点buffer
    if( FAILED( g_pd3dDevice->CreateVertexBuffer( 3*sizeof(CUSTOMVERTEX),
                                                  0, D3DFVF_CUSTOMVERTEX,
                                                  D3DPOOL_DEFAULT, &g_pVB, NULL ) ) )
    {
        return E_FAIL;
    }

    // 锁定内存,复制
    VOID* pVertices;
    if( FAILED( g_pVB->Lock( 0, sizeof(Vertices), (void**)&pVertices, 0 ) ) )
        return E_FAIL;
    memcpy( pVertices, Vertices, sizeof(Vertices) );
    g_pVB->Unlock();

    return S_OK;
}

//-----------------------------------------------------------------------------
// Name: Cleanup()
// Desc: Releases all previously initialized objects
//-----------------------------------------------------------------------------
VOID Cleanup()
{
    if( g_pVB != NULL )
        g_pVB->Release();

    if( g_pd3dDevice != NULL )
        g_pd3dDevice->Release();

    if( g_pD3D != NULL )
        g_pD3D->Release();
}

//-----------------------------------------------------------------------------
// Name: Render()
// Desc: Draws the scene
//-----------------------------------------------------------------------------
VOID Render()
{
    // Clear the backbuffer to a blue color
    g_pd3dDevice->Clear( 0, NULL, D3DCLEAR_TARGET, D3DCOLOR_XRGB(0,0,255), 1.0f, 0 );

    // Begin the scene
    if( SUCCEEDED( g_pd3dDevice->BeginScene() ) )
    {
        g_pd3dDevice->SetStreamSource( 0, g_pVB, 0, sizeof(CUSTOMVERTEX) );
        g_pd3dDevice->SetFVF( D3DFVF_CUSTOMVERTEX );
		//绘制三角形
        g_pd3dDevice->DrawPrimitive( D3DPT_TRIANGLELIST, 0, 1 );

        // End the scene
        g_pd3dDevice->EndScene();
    }

    // Present the backbuffer contents to the display
    g_pd3dDevice->Present( NULL, NULL, NULL, NULL );
}

//-----------------------------------------------------------------------------
// Name: MsgProc()
// Desc: The window's message handler
//-----------------------------------------------------------------------------
LRESULT WINAPI MsgProc( HWND hWnd, UINT msg, WPARAM wParam, LPARAM lParam )
{
    switch( msg )
    {
        case WM_DESTROY:
            Cleanup();
            PostQuitMessage( 0 );
            return 0;
    }

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

//-----------------------------------------------------------------------------
// Name: WinMain()
// Desc: The application's entry point
//-----------------------------------------------------------------------------
INT WINAPI WinMain( HINSTANCE hInst, HINSTANCE, LPSTR, INT )
{
    // Register the window class
    WNDCLASSEX wc = { sizeof(WNDCLASSEX), CS_CLASSDC, MsgProc, 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,
                              GetDesktopWindow(), NULL, wc.hInstance, NULL );

    // Initialize Direct3D
    if( SUCCEEDED( InitD3D( hWnd ) ) )
    {
        // Create the vertex buffer
        if( SUCCEEDED( InitVB() ) )
        {
            // Show the window
            ShowWindow( hWnd, SW_SHOWDEFAULT );
            UpdateWindow( hWnd );

            // Enter the message loop
            MSG msg;
            ZeroMemory( &msg, sizeof(msg) );
            while( msg.message!=WM_QUIT )
            {
                if( PeekMessage( &msg, NULL, 0U, 0U, PM_REMOVE ) )
                {
                    TranslateMessage( &msg );
                    DispatchMessage( &msg );
                }
                else
                    Render();
            }
        }
    }

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

Project下载:

http://download.csdn.net/detail/fox64194167/4608955 (CSDN下载,免积分)
Vertices(本站下载)
相关文章:

1.DirectX 9.0 C++ 教程 开发环境设定

2.DirectX 9.0 C++ 教程 第一个程序

3.DirectX 9.0 C++ 教程 绘制三角形

4.DirectX 9.0 C++ 教程 关于Perspective projection,Matrices,摄像头,旋转

5.DirectX 9.0 C++ 教程 光照

6.DirectX 9.0 C++ 教程 Texture 纹理映射

7.DirectX 9.0 C++ 教程 字体 迟到的helloworld

8. DirectX 9.0 C++ 教程 使用3ds max 创建的模型 xfile,mesh

208

4 Responses to DirectX 9.0 C++ 教程 绘制三角形

Leave a Reply

Name and Email Address are required fields.
Your email will not be published or shared with third parties.