fog.cpp

是《3D游戏编程》的代码 买了这本书

//-----------------------------------------------------------------------------
// 名称: RenderSene.cpp
// 
// 功能: 进行3D场景的渲染——使用显示内存的顶点缓冲区。
//       
//-----------------------------------------------------------------------------

// 包含Direct3D头文件
#include <d3d8.h>
#include <d3dx8.h>

// Windows类的名称宏定义
#define  MY_WINCLASS_NAME      "Direct3D"

#define KEYDOWN(vk_code)  ((GetAsyncKeyState(vk_code) & 0x8000)? 1 : 0)
#define KEYUP(vk_code)    ((GetAsyncKeyState(vk_code) & 0x8000)? 0 : 1)

#define VK_1  0x31    // 按键 “1”的值0x31
#define VK_2  0x32

#define SAFE_RELEASE(p)      { if(p) { (p)->Release(); (p)=NULL; } }

inline DWORD FtoDW( FLOAT f ) { return *((DWORD*)&f); }

struct PLAYER
{
    D3DXVECTOR3    LookAt[3];
};

// 定义个表示顶点的结构
struct FOGVERTEX
{
        D3DXVECTOR3 p;
        D3DXVECTOR3 n;
        FLOAT       tu, tv;
};


struct CUSTOMVERTEX01
{
    D3DXVECTOR3 position; 
    D3DXVECTOR3 normal;   
};

struct CUSTOMVERTEX02
{
    D3DXVECTOR3 position; 
    D3DCOLOR    color;  
    FLOAT       tu, tv;   
};

struct CUSTOMVERTEX
{
    FLOAT x, y, z; // x,y,z表示点的三维坐标值，
    DWORD color;        // 顶点颜色
};

// 自定义的顶点格式
#define D3DFVF_CUSTOMVERTEX (D3DFVF_XYZ|D3DFVF_DIFFUSE)
#define D3DFVF_FOGVERTEX (D3DFVF_XYZ|D3DFVF_NORMAL|D3DFVF_TEX1)
#define D3DFVF_CUSTOMVERTEX01 (D3DFVF_XYZ|D3DFVF_NORMAL)
#define D3DFVF_CUSTOMVERTEX02 (D3DFVF_XYZ|D3DFVF_DIFFUSE|D3DFVF_TEX1)

// 定义全局变量
LPDIRECT3D8             g_pMyD3D          = NULL; // 定义Direct3D对象的指针
LPDIRECT3DDEVICE8       g_pMyd3dDevice    = NULL; // 定义Direct3D设备指针
LPDIRECT3DVERTEXBUFFER8 g_pMyVxBufferRec     = NULL; // 定义顶点缓冲区对象指针
LPDIRECT3DVERTEXBUFFER8 g_pMyVxBufferLine     = NULL;
LPDIRECT3DVERTEXBUFFER8 g_pMyVxBufferEllipse    = NULL;
LPDIRECT3DVERTEXBUFFER8 g_pVB        = NULL;
LPDIRECT3DVERTEXBUFFER8 g_pTerrainVB = NULL;

// 定义用于墙面渲染的纹理指针变量
LPDIRECT3DTEXTURE8      g_pTextureWall   = NULL; 

// 定义用于地面渲染的纹理指针变量
LPDIRECT3DTEXTURE8      g_pTextureLand   = NULL; 

D3DXVECTOR3             g_lightPosition;

BOOL                    g_TextureFilter = TRUE;
DWORD                   g_dwNumTerrainVertices = 0;


PLAYER  g_Player;
float   g_Angle = 0;

#define LINE_VECTOR_NUM 20


#define GRID_WIDTH       20.0f
#define NUM_GRID         20


#define ELLIPSE_RINGS     20
#define ELLIPSE_SEGMENTS  20


//-----------------------------------------------------------------------------
// 名称: GenerateTerrain()
// 功能: 初始化用于地面的顶点
//       
//-----------------------------------------------------------------------------
GenerateTerrain( LPDIRECT3DDEVICE8 pd3dDevice, DWORD dwNumSegments,
                                       FLOAT fScale )
{
    HRESULT hr;

    g_dwNumTerrainVertices = 2 * dwNumSegments * (dwNumSegments);

    // Destroy the old vertex buffer, if any
    SAFE_RELEASE( g_pTerrainVB );

    // Create a vertex buffer
    hr = pd3dDevice->CreateVertexBuffer( g_dwNumTerrainVertices*sizeof(FOGVERTEX),
                                         D3DUSAGE_WRITEONLY, D3DFVF_FOGVERTEX,
                                         D3DPOOL_MANAGED, &g_pTerrainVB );
    if( FAILED(hr) )
        return hr;

    FOGVERTEX* pVertices = NULL;
    hr = g_pTerrainVB->Lock( 0, g_dwNumTerrainVertices*sizeof(FOGVERTEX),
                             (BYTE**)&pVertices, 0 );
    if( FAILED(hr) )
        return hr;

    // Generate a spiralized trianglestrip
    for( DWORD ring = 0; ring < dwNumSegments; ring++ )
    {
        for( DWORD seg=0; seg < dwNumSegments; seg++ )
        {
            FLOAT fTheta = (seg*2*D3DX_PI) / dwNumSegments;
            FLOAT r0     = (ring + fTheta/(2*D3DX_PI))*fScale/dwNumSegments;
            FLOAT r1     = r0 + fScale/dwNumSegments;

            FLOAT x   = (FLOAT)sin( fTheta );
            FLOAT z   = (FLOAT)cos( fTheta );

            FLOAT y0  =  (FLOAT)sin(r0*z*z+r0*x*x);
            FLOAT nx0 = -(FLOAT)cos(r0*z*z+r0*x*x)*r0*2*x;
            FLOAT ny0 = 1.0f;
            FLOAT nz0 = -(FLOAT)cos(r0*z*z+r0*x*x)*r0*2*z;

            FLOAT y1  =  (FLOAT)sin(r1*z*z+r1*x*x);
            FLOAT nx1 = -(FLOAT)cos(r1*z*z+r1*x*x)*r1*2*x;
            FLOAT ny1 = 1.0f;
            FLOAT nz1 = -(FLOAT)cos(r1*z*z+r1*x*x)*r1*2*z;

            // Add two vertices to the strip at each step
            pVertices->p.x = r0*x;
            pVertices->p.y = y0;
            pVertices->p.z = r0*z;
            pVertices->n.x = nx0;
            pVertices->n.y = ny0;
            pVertices->n.z = nz0;
            pVertices->tu  = (r0*x)/fScale;
            pVertices->tv  = (r0*z)/fScale;
            pVertices++;

            pVertices->p.x = r1*x;
            pVertices->p.y = y1;
            pVertices->p.z = r1*z;
            pVertices->n.x = nx1;
            pVertices->n.y = ny1;
            pVertices->n.z = nz1;
            pVertices->tu  = (r1*x)/fScale;
            pVertices->tv  = (r1*z)/fScale;
            pVertices++;
        }
    }

    g_pTerrainVB->Unlock();

    return S_OK;
}

//-----------------------------------------------------------------------------
// 名称: SetupPointLights()
// 功能: 建立一个点灯光
//-----------------------------------------------------------------------------
VOID SetupPointLights(D3DXVECTOR3 Position, ULONG ulIndex, D3DCOLORVALUE Color)
{
    D3DXVECTOR3 vecDir;
    D3DLIGHT8 light;
    ZeroMemory( &light, sizeof(D3DLIGHT8) );
    light.Type       = D3DLIGHT_POINT ;
    light.Diffuse.r  = Color.r;
    light.Diffuse.g  = Color.g;
    light.Diffuse.b  = Color.b;

	light.Position	 = Position;				 
    light.Range       = 200.0f;
	light.Attenuation0 = 1.1f;
    g_pMyd3dDevice->SetLight( ulIndex, &light );
    g_pMyd3dDevice->LightEnable( 0, TRUE );
    g_pMyd3dDevice->SetRenderState( D3DRS_LIGHTING, TRUE );
	return;

}

//-----------------------------------------------------------------------------
// 名称: InitD3D()
// 功能: 初始化3D环境的函数，函数中创建了Direct3D对象和Direct3D设备。
//       函数返回E_FAIL表示失败，返回E_OK表示成功。
//-----------------------------------------------------------------------------
HRESULT InitMy3D( HWND hWnd )
{
    // 创建Direct3D对象，是使用Direct3D的第一步操作
    if( NULL == ( g_pMyD3D = Direct3DCreate8( D3D_SDK_VERSION ) ) )
        return E_FAIL;

    // 获取当前Windows桌面的显示模式，保存到定义的d3ddm结构中
    D3DDISPLAYMODE d3ddm;
    if( FAILED( g_pMyD3D->GetAdapterDisplayMode( D3DADAPTER_DEFAULT, &d3ddm ) ) )
        return E_FAIL;

	// 定义Present结构   
    D3DPRESENT_PARAMETERS d3dpp; 

    // 把结构清零，创建设备时，结构中成员值为0表示使用缺省值 
    ZeroMemory( &d3dpp, sizeof(d3dpp) );

	// 指定创建的Direct3D是支持窗口的设备
    d3dpp.Windowed = TRUE;

	// 指定交换效果为D3DSWAPEFFECT_DISCARD，即把后台表面显示到前台表面以后，
	// 原来的后台表面包含的信息自动丢失
    d3dpp.SwapEffect = D3DSWAPEFFECT_DISCARD;

	d3dpp.EnableAutoDepthStencil = TRUE;
    d3dpp.AutoDepthStencilFormat = D3DFMT_D16;

	// 后台缓冲区的的点格式与当前显示模式的点格式一致
    d3dpp.BackBufferFormat = d3ddm.Format;

	// 创建Direct3D设备:
	// 1. 使用主显卡创建设备，参数D3DADAPTER_DEFAULT
	// 2. 设备类型为硬件抽象设备，使用硬件加速功能，参数D3DDEVTYPE_HAL
    // 3. 使用前面创建的窗口用于目标表面的显示，参数hWnd
	// 4. 指定设备的对于顶点的处理能力为软件处理顶点，这是为了能够让所有
	//    的显卡支持,参数D3DCREATE_SOFTWARE_VERTEXPROCESSING
    if( FAILED( g_pMyD3D->CreateDevice( D3DADAPTER_DEFAULT, D3DDEVTYPE_HAL, hWnd,
                                      D3DCREATE_SOFTWARE_VERTEXPROCESSING,
                                      &d3dpp, &g_pMyd3dDevice ) ) )
    {
        return E_FAIL;
    }

    g_pMyd3dDevice->SetRenderState( D3DRS_CULLMODE, D3DCULL_NONE );

    g_pMyd3dDevice->SetRenderState( D3DRS_LIGHTING, FALSE );
    g_pMyd3dDevice->SetRenderState( D3DRS_ZENABLE, TRUE );

	// 创建墙面使用的纹理
    if( FAILED( D3DXCreateTextureFromFile( g_pMyd3dDevice, "tree01S.tga",
                                           &g_pTextureWall ) ) )
        return E_FAIL;

	// 创建地面使用的纹理
    if( FAILED( D3DXCreateTextureFromFile( g_pMyd3dDevice, "seafloor.bmp",
                                           &g_pTextureLand ) ) )
        return E_FAIL;

	// 创建表示墙面的顶点缓冲区
    if( FAILED( g_pMyd3dDevice->CreateVertexBuffer( 4*sizeof(CUSTOMVERTEX02),
                                                  0, D3DFVF_CUSTOMVERTEX02,
                                                  D3DPOOL_DEFAULT, &g_pMyVxBufferRec ) ) )
    {
        return E_FAIL;
    } 
	CUSTOMVERTEX02* pVertices1;
	// 获得顶点缓冲区的内存指针，并锁定顶点缓冲区
    if( FAILED( g_pMyVxBufferRec->Lock( 0, 4*sizeof(CUSTOMVERTEX02), (BYTE**)&pVertices1, 0 ) ) )
	{
        return E_FAIL;
	}

	// 初始化顶点数据到顶点缓冲区中
    pVertices1->position = D3DXVECTOR3(-1.5f, 0.0f, 0.0f);
	pVertices1->color =  0xffffffff;
	pVertices1->tu = 0.0f;
	pVertices1->tv = 1.0f;
	pVertices1++;
    pVertices1->position = D3DXVECTOR3(-1.5f, 3.0f, 0.0f);
	pVertices1->color =  0xffffffff;
	pVertices1->tu = 0.0f;
	pVertices1->tv = 0.0f;

	pVertices1++;
	pVertices1->position = D3DXVECTOR3( 1.5f, 0.0f, 0.0f);
	pVertices1->color =  0xffffffff;
	pVertices1->tu = 1.0f;
	pVertices1->tv = 1.0f;

	pVertices1++;
	pVertices1->position = D3DXVECTOR3( 1.5f, 3.0f, 0.0f);
	pVertices1->color =  0xffffffff;
	pVertices1->tu = 1.0f;
	pVertices1->tv = 0.0f;

	// 顶点缓冲区的解锁操作
    g_pMyVxBufferRec->Unlock();
	

	// 创建地面顶点缓冲区
    GenerateTerrain( g_pMyd3dDevice, 10, 100.0f );

	D3DMATERIAL8 mtrl;
	mtrl.Ambient.r = 1.0f; 
	mtrl.Ambient.g = 1.0f; 
	mtrl.Ambient.b = 1.0f; 
	mtrl.Ambient.a = 0.0f; 

    g_pMyd3dDevice->SetMaterial( &mtrl );
    g_pMyd3dDevice->SetRenderState( D3DRS_AMBIENT,  0x44444444 );

	D3DCOLORVALUE color;
    color.r = 0x5f;
	color.b = 0x5f;
	color.g = 0x5f;
	SetupPointLights(D3DXVECTOR3(0,20,0), 0, color);

	g_Player.LookAt[0] = D3DXVECTOR3( 0.0f, 1.6f,-4.0f );
	g_Player.LookAt[1] = D3DXVECTOR3( 0.0f, 1.6f,-3.0f );
	g_Player.LookAt[2] = D3DXVECTOR3( 0.0f, 1.0f, 0.0f );