Directx9.0 学习教程5 光照

光照

1.      首先需要定义这样的顶点结构

struct CUSTOMVERTEX
{
    D3DXVECTOR3position; // 顶点
    D3DXVECTOR3normal;   // 法向量
};
// Custom flexible vertex format (FVF).
#define D3DFVF_CUSTOMVERTEX (D3DFVF_XYZ|D3DFVF_NORMAL)

2. 然后创建一个圆柱体顶点模型

// Create the vertex buffer.
   if( FAILED(g_pd3dDevice->CreateVertexBuffer(50 * 2 * sizeof( CUSTOMVERTEX),
                                                 0, D3DFVF_CUSTOMVERTEX,
                                                 D3DPOOL_DEFAULT, &g_pVB, NULL ) ))
   {
       return E_FAIL;
    }

   // Fill the vertex buffer. We arealgorithmically generating a cylinder
   // here, including the normals, which are usedfor lighting.
   CUSTOMVERTEX* pVertices;
   if( FAILED(g_pVB->Lock(0, 0, ( void** )&pVertices,0 ) ) )
       return E_FAIL;
   for( DWORDi = 0; i< 50; i++ )
   {
       FLOAT theta= ( 2 * D3DX_PI * i) / ( 50 - 1 );
       pVertices[2 * i + 0].position = D3DXVECTOR3( sinf(theta ), -1.0f, cosf(theta ) );
       pVertices[2 * i + 0].normal = D3DXVECTOR3( sinf(theta ), 0.0f, cosf(theta ) );
       pVertices[2 * i + 1].position = D3DXVECTOR3( sinf(theta ), 1.0f, cosf(theta ) );
       pVertices[2 * i + 1].normal = D3DXVECTOR3( sinf(theta ), 0.0f, cosf(theta ) );
   }
   g_pVB->Unlock();
 

3.      创建灯光

// Set up a material. The material here just has thediffuse and ambient
   // colors set to yellow. Note that only onematerial can be used at a time.
   D3DMATERIAL9 mtrl;  //因为有光照，所以需要创建一个材质来接受
   ZeroMemory( &mtrl, sizeof( D3DMATERIAL9 ) );
   mtrl.Diffuse.r = mtrl.Ambient.r =1.0f;
   mtrl.Diffuse.g = mtrl.Ambient.g =1.0f;
   mtrl.Diffuse.b = mtrl.Ambient.b =0.0f;
   mtrl.Diffuse.a = mtrl.Ambient.a =1.0f;
   g_pd3dDevice->SetMaterial( &mtrl);

   // Set up a white, directional light, with anoscillating direction.
   // Note that many lights may be active at atime (but each one slows down
   // the rendering of our scene). However, herewe are just using one. Also,
   // we need to set the D3DRS_LIGHTINGrenderstate to enable lighting
   D3DXVECTOR3 vecDir;
   D3DLIGHT9 light;//创建灯光
   ZeroMemory( &light, sizeof( D3DLIGHT9 ) );
   light.Type= D3DLIGHT_DIRECTIONAL; //设置为平行光
   light.Diffuse.r = 1.0f;
   light.Diffuse.g = 1.0f;
   light.Diffuse.b = 1.0f;
   vecDir = D3DXVECTOR3(cosf( timeGetTime()/ 350.0f ), //方向随时间变化
                          1.0f,
                          sinf( timeGetTime()/ 350.0f ) );
   D3DXVec3Normalize( ( D3DXVECTOR3* )&light.Direction, &vecDir); //单位化方向
   light.Range= 1000.0f;//方向光这个参数无效
   g_pd3dDevice->SetLight( 0, &light);
   g_pd3dDevice->LightEnable( 0, TRUE);
   g_pd3dDevice->SetRenderState( D3DRS_LIGHTING,TRUE ); //开启光照

   // Finally, turn on some ambient light.
   g_pd3dDevice->SetRenderState( D3DRS_AMBIENT,0x00202020 ); //设置环境光

比较简单，

效果：

全部代码:

//-----------------------------------------------------------------------------
// File: Lights.cpp
//
// Desc: Rendering 3D geometry is much more interesting when dynamic lighting
//       is added to the scene. To use lighting in D3D, you must create one or
//       lights, setup a material, and make sure your geometry contains surface
//       normals. Lights may have a position, a color, and be of a certain type
//       such as directional (light comes from one direction), point (light
//       comes from a specific x,y,z coordinate and radiates in all directions)
//       or spotlight. Materials describe the surface of your geometry,
//       specifically, how it gets lit (diffuse color, ambient color, etc.).
//       Surface normals are part of a vertex, and are needed for the D3D's
//       internal lighting calculations.
//
// Copyright (c) Microsoft Corporation. All rights reserved.
//-----------------------------------------------------------------------------
#include <Windows.h>
#include <mmsystem.h>
#include <d3dx9.h>
#pragma warning( disable : 4996 ) // disable deprecated warning
#include <strsafe.h>
#pragma warning( default : 4996 )

//-----------------------------------------------------------------------------
// 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

// A structure for our custom vertex type. We added a normal, and omitted the
// color (which is provided by the material)
struct CUSTOMVERTEX
{
    D3DXVECTOR3 position; // The 3D position for the vertex
    D3DXVECTOR3 normal;   // The surface normal for the vertex
};

// Our custom FVF, which describes our custom vertex structure
#define D3DFVF_CUSTOMVERTEX (D3DFVF_XYZ|D3DFVF_NORMAL)

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

    // Set up the structure used to create the D3DDevice. Since we are now
    // using more complex geometry, we will create a device with a zbuffer.
    D3DPRESENT_PARAMETERS d3dpp;
    ZeroMemory( &d3dpp, sizeof( d3dpp ) );
    d3dpp.Windowed = TRUE;
    d3dpp.SwapEffect = D3DSWAPEFFECT_DISCARD;
    d3dpp.BackBufferFormat = D3DFMT_UNKNOWN;
    d3dpp.EnableAutoDepthStencil = TRUE;
    d3dpp.AutoDepthStencilFormat = D3DFMT_D16;

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

    // Turn off culling
    g_pd3dDevice->SetRenderState( D3DRS_CULLMODE, D3DCULL_NONE );

    // Turn on the zbuffer
    g_pd3dDevice->SetRenderState( D3DRS_ZENABLE, TRUE );

    return S_OK;
}

//-----------------------------------------------------------------------------
// Name: InitGeometry()
// Desc: Creates the scene geometry
//-----------------------------------------------------------------------------
HRESULT InitGeometry()
{
    // Create the vertex buffer.
    if( FAILED( g_pd3dDevice->CreateVertexBuffer( 50 * 2 * sizeof( CUSTOMVERTEX ),
                                                  0, D3DFVF_CUSTOMVERTEX,
                                                  D3DPOOL_DEFAULT, &g_pVB, NULL ) ) )
    {
        return E_FAIL;
    }

    // Fill the vertex buffer. We are algorithmically generating a cylinder
    // here, including the normals, which are used for lighting.
    CUSTOMVERTEX* pVertices;
    if( FAILED( g_pVB->Lock( 0, 0, ( void** )&pVertices, 0 ) ) )
        return E_FAIL;
    for( DWORD i = 0; i < 50; i++ )
    {
        FLOAT theta = ( 2 * D3DX_PI * i ) / ( 50 - 1 );
        pVertices[2 * i + 0].position = D3DXVECTOR3( sinf( theta ), -1.0f, cosf( theta ) );
        pVertices[2 * i + 0].normal = D3DXVECTOR3( sinf( theta ), 0.0f, cosf( theta ) );
        pVertices[2 * i + 1].position = D3DXVECTOR3( sinf( theta ), 1.0f, cosf( theta ) );
        pVertices[2 * i + 1].normal = D3DXVECTOR3( sinf( theta ), 0.0f, cosf( theta ) );
    }
    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: SetupMatrices()
// Desc: Sets up the world, view, and projection transform matrices.
//-----------------------------------------------------------------------------
VOID SetupMatrices()
{
    // Set up world matrix
    D3DXMATRIXA16 matWorld;
    D3DXMatrixIdentity( &matWorld );
    D3DXMatrixRotationX( &matWorld, D3DX_PI/4);
    g_pd3dDevice->SetTransform( D3DTS_WORLD, &matWorld );

    // Set up our view matrix. A view matrix can be defined given an eye point,
    // a point to lookat, and a direction for which way is up. Here, we set the
    // eye five units back along the z-axis and up three units, look at the
    // origin, and define "up" to be in the y-direction.
    D3DXVECTOR3 vEyePt( 0.0f, 3.0f,-5.0f );
    D3DXVECTOR3 vLookatPt( 0.0f, 0.0f, 0.0f );
    D3DXVECTOR3 vUpVec( 0.0f, 1.0f, 0.0f );
    D3DXMATRIXA16 matView;
    D3DXMatrixLookAtLH( &matView, &vEyePt, &vLookatPt, &vUpVec );
    g_pd3dDevice->SetTransform( D3DTS_VIEW, &matView );

    // For the projection matrix, we set up a perspective transform (which
    // transforms geometry from 3D view space to 2D viewport space, with
    // a perspective divide making objects smaller in the distance). To build
    // a perpsective transform, we need the field of view (1/4 pi is common),
    // the aspect ratio, and the near and far clipping planes (which define at
    // what distances geometry should be no longer be rendered).
    D3DXMATRIXA16 matProj;
    D3DXMatrixPerspectiveFovLH( &matProj, D3DX_PI / 4, 1.0f, 1.0f, 100.0f );
    g_pd3dDevice->SetTransform( D3DTS_PROJECTION, &matProj );
}

//-----------------------------------------------------------------------------
// Name: SetupLights()
// Desc: Sets up the lights and materials for the scene.
//-----------------------------------------------------------------------------
VOID SetupLights()
{
    // Set up a material. The material here just has the diffuse and ambient
    // colors set to yellow. Note that only one material can be used at a time.
    D3DMATERIAL9 mtrl;
    ZeroMemory( &mtrl, sizeof( D3DMATERIAL9 ) );
    mtrl.Diffuse.r = mtrl.Ambient.r = 1.0f;
    mtrl.Diffuse.g = mtrl.Ambient.g = 1.0f;
    mtrl.Diffuse.b = mtrl.Ambient.b = 0.0f;
    mtrl.Diffuse.a = mtrl.Ambient.a = 1.0f;
    g_pd3dDevice->SetMaterial( &mtrl );

    // Set up a white, directional light, with an oscillating direction.
    // Note that many lights may be active at a time (but each one slows down
    // the rendering of our scene). However, here we are just using one. Also,
    // we need to set the D3DRS_LIGHTING renderstate to enable lighting
    D3DXVECTOR3 vecDir;
    D3DLIGHT9 light;
    ZeroMemory( &light, sizeof( D3DLIGHT9 ) );
    light.Type = D3DLIGHT_DIRECTIONAL;
    light.Diffuse.r = 1.0f;
    light.Diffuse.g = 1.0f;
    light.Diffuse.b = 1.0f;
    vecDir = D3DXVECTOR3( cosf( timeGetTime() / 350.0f ),
                          1.0f,
                          sinf( timeGetTime() / 350.0f ) );
    D3DXVec3Normalize( ( D3DXVECTOR3* )&light.Direction, &vecDir );
    light.Range = 1000.0f;
    g_pd3dDevice->SetLight( 0, &light );
    g_pd3dDevice->LightEnable( 0, TRUE );
    g_pd3dDevice->SetRenderState( D3DRS_LIGHTING, TRUE );

    // Finally, turn on some ambient light.
    g_pd3dDevice->SetRenderState( D3DRS_AMBIENT, 0x00202020 );
}

//-----------------------------------------------------------------------------
// Name: Render()
// Desc: Draws the scene
//-----------------------------------------------------------------------------
VOID Render()
{
    // Clear the backbuffer and the zbuffer
    g_pd3dDevice->Clear( 0, NULL, D3DCLEAR_TARGET | D3DCLEAR_ZBUFFER,
                         D3DCOLOR_XRGB( 0, 0, 255 ), 1.0f, 0 );

    // Begin the scene
    if( SUCCEEDED( g_pd3dDevice->BeginScene() ) )
    {
        // Setup the lights and materials
        SetupLights();

        // Setup the world, view, and projection matrices
        SetupMatrices();

        // Render the vertex buffer contents
        g_pd3dDevice->SetStreamSource( 0, g_pVB, 0, sizeof( CUSTOMVERTEX ) );
        g_pd3dDevice->SetFVF( D3DFVF_CUSTOMVERTEX );
        g_pd3dDevice->DrawPrimitive( D3DPT_TRIANGLESTRIP, 0, 2 * 50 - 2 );

        // 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 wWinMain( HINSTANCE hInst, HINSTANCE, LPWSTR, INT )
{
    UNREFERENCED_PARAMETER( hInst );

    // Register the window class
    WNDCLASSEX wc =
    {
        sizeof( WNDCLASSEX ), CS_CLASSDC, MsgProc, 0L, 0L,
        GetModuleHandle( NULL ), NULL, NULL, NULL, NULL,
        L"D3D Tutorial", NULL
    };
    RegisterClassEx( &wc );

    // Create the application's window
    HWND hWnd = CreateWindow( L"D3D Tutorial", L"D3D Tutorial 04: Lights",
                              WS_OVERLAPPEDWINDOW, 100, 100, 300, 300,
                              NULL, NULL, wc.hInstance, NULL );

    // Initialize Direct3D
    if( SUCCEEDED( InitD3D( hWnd ) ) )
    {
        // Create the geometry
        if( SUCCEEDED( InitGeometry() ) )
        {
            // 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( L"D3D Tutorial", wc.hInstance );
    return 0;
}