第11讲 天空文档格式.docx

第11讲 天空文档格式.docx

《第11讲 天空文档格式.docx》由会员分享，可在线阅读，更多相关《第11讲 天空文档格式.docx（18页珍藏版）》请在冰豆网上搜索。

#defineD3DFVF_CUSTOMVETEX2（D3DFVF_XYZ|D3DFVF_TEX1）

classCCubeSky

private:

LPDIRECT3DDEVICE9m_pd3dDevice;

LPDIRECT3DVERTEXBUFFER9m_pVB;

LPDIRECT3DINDEXBUFFER9m_pIB;

LPDIRECT3DTEXTURE9m_pTexScene[6];

floatlen;

public:

CCubeSky（LPDIRECT3DDEVICE9pd3dDevice）;

~CCubeSky（void）;

HRESULTVBInit（）;

voidRender（）;

boolSetTexture（constWCHAR*FileTexture,intflag）;

CCubeSky.cpp

#include"

CubeSky.h"

CCubeSky:

:

CCubeSky（LPDIRECT3DDEVICE9pd3dDevice）

m_pd3dDevice=pd3dDevice;

this->

m_pIB=NULL;

m_pVB=NULL;

len=100.0f;

}

~CCubeSky（void）

{}

HRESULTCCubeSky:

VBInit（）

//创建天空盒需要的8个顶点

CUSTOMVERTEX2gCubeVerts[]=

{

//z方向点和纹理坐标

{-len,0.0f,-len,1.0f,1.0f},//0

{-len,len,-len,1.0f,0.0f},//1

{len,0.0f,-len,0.0f,1.0f},//2

{len,len,-len,0.0f,0.0f},//3

{len,0.0f,len,1.0f,1.0f},//4

{len,len,len,1.0f,0.0f},//5

{-len,0.0f,len,0.0f,1.0f},//6

{-len,len,len,0.0f,0.0f},//7

//x方向点和纹理坐标

{len,0.0f,-len,1.0f,1.0f},//2-8

{len,len,-len,1.0f,0.0f},//3-9

{len,0.0f,len,0.0f,1.0f},//4-10

{len,len,len,0.0f,0.0f},//5-11

{-len,0.0f,-len,0.0f,1.0f},//0-12

{-len,len,-len,0.0f,0.0f},//1-13

{-len,0.0f,len,1.0f,1.0f},//6-14

{-len,len,len,1.0f,0.0f},//7-15

//y方向点和纹理坐标

{-len,0.0f,-len,1.0f,0.0f},//0-16

{len,0.0f,-len,0.0f,0.0f},//2-17

{-len,0.0f,len,1.0f,1.0f},//6-18

{len,0.0f,len,0.0f,1.0f},//4-19

{-len,len,-len,1.0f,1.0f},//1-20

{len,len,-len,0.0f,1.0f},//3-21

{len,len,len,0.0f,0.0f},//5-22

{-len,len,len,1.0f,0.0f},//7-23

};

//创建天空盒需要的顶点的索引

WORDgCubeIndices[]=

{2,3,1,//z方向

2,1,0,//

6,7,5,//

6,5,4,//

10,11,9,//x方向

10,9,8,//

12,13,15,//

12,15,14,//

16,18,19,//y方向

16,19,17,//

20,21,22,//

20,22,23

//创建顶点缓冲区

if（FAILED（m_pd3dDevice->

CreateVertexBuffer（sizeof（gCubeVerts）,

0,

D3DFVF_CUSTOMVETEX2,

D3DPOOL_DEFAULT,

&

m_pVB,

NULL

）））

returnE_FAIL;

}

VOID*pVertices;

//锁定顶点缓冲区

if（FAILED（m_pVB->

Lock（0,sizeof（gCubeVerts）,

（void**）&

pVertices,0）））

//把顶点数组的数据拷贝到顶点缓冲区中

memcpy（pVertices,gCubeVerts,sizeof（gCubeVerts））;

m_pVB->

Unlock（）;

//解锁顶点缓冲区

//创建索引缓冲区

CreateIndexBuffer（sizeof（gCubeIndices）,

D3DFMT_INDEX16,

m_pIB,

VOID*pIndices;

//锁定索引缓冲区

if（FAILED（m_pIB->

Lock（0,sizeof（gCubeIndices）,

pIndices,0）））

//把索引数组的值拷贝索引缓冲区中

memcpy（pIndices,gCubeIndices,sizeof（gCubeIndices））;

m_pIB->

//解锁索引缓冲区

returnS_OK;

boolCCubeSky:

SetTexture（constWCHAR*FileTexture,intflag）

if（FAILED（D3DXCreateTextureFromFile（m_pd3dDevice,FileTexture,

m_pTexScene[flag]）））

returnfalse;

returntrue;

voidCCubeSky:

Render（）

D3DXMATRIXmatrix,smatrix,tmatrix,rmatrix;

//m_Camera.ProcInput（）;

//设置数据源

m_pd3dDevice->

SetStreamSource（0,m_pVB,0,sizeof（CUSTOMVERTEX2））;

SetFVF（D3DFVF_CUSTOMVETEX2）;

SetIndices（m_pIB）;

SetRenderState（D3DRS_CULLMODE,D3DCULL_CCW）;

//背面消隐

SetRenderState（D3DRS_LIGHTING,false）;

//光照关闭

SetRenderState（D3DRS_ZENABLE,false）;

//关闭Zbuffer

//SetProjection（）;

//投影

//画天空盒设置纹理

SetTexture（0,m_pTexScene[0]）;

DrawIndexedPrimitive（D3DPT_TRIANGLELIST,0,0,4,0,2）;

SetTexture（0,m_pTexScene[1]）;

DrawIndexedPrimitive（D3DPT_TRIANGLELIST,0,4,4,6,2）;

SetTexture（0,m_pTexScene[2]）;

DrawIndexedPrimitive（D3DPT_TRIANGLELIST,0,8,4,12,2）;

SetTexture（0,m_pTexScene[3]）;

DrawIndexedPrimitive（D3DPT_TRIANGLELIST,0,12,4,18,2）;

SetTexture（0,m_pTexScene[4]）;

DrawIndexedPrimitive（D3DPT_TRIANGLELIST,0,16,4,24,2）;

SetTexture（0,m_pTexScene[5]）;

DrawIndexedPrimitive（D3DPT_TRIANGLELIST,0,20,4,30,2）;

球形天空构造

球面天空是通过在半球面上进行纹理贴图实现的，因此，需要分割一个半球面获得各个顶点，然后定义顶点的灵活顶点格式，设置和计算每个顶点的xyz坐标和纹理uv坐标，最后将顶点数据送入渲染管道流水线进行处理，如图所示

假设半球面上的任意点p=（px,py,pz）半球体的半径为r，α和β为相应的经度角和纬度角，如图下所示。

从图中可以看出，经度角α的取值范围在区间[0,2π]内，而纬度角β的取值范围在区间[0,π/2]内。

所以顶点p的坐标计算公式如下：

接下来考虑纹理坐标的计算。

若将2π除以经度角就可以得到维度线的条数，而若将π/2除以维度角就可以得到经度线的条数。

因此，根据p点的经度角α和维度角β就可以计算出p点的纹理坐标。

可以按照下面代码计算出p点的坐标和纹理坐标。

m_fSkyboxRadius=fRadius;

//半球体的半径

m_nNumLatitudes=360/nAlpha;

//维度线的条数

m_nNumLongitudes=90/nBeta;

//经度线的条数

m_nVertsPerLongi=m_nNumLatitudes+1;

//每条经度线上的顶点数

m_nVertsPerLati=m_nNumLongitudes+1;

//每条维度线上的顶点数

m_nNumVertices=m_nVertsPerLati*m_nVertsPerLongi;

//灵活顶点格式

structSkyBoxVERTEX

FLOAT_x,_y,_z;

FLOAT_u,_v;

SkyBoxVERTEX（FLOATx,FLOATy,FLOATz,FLOATu,FLOATv）

:

_x（x）,_y（y）,_z（z）,_u（u）,_v（v）{}

staticconstDWORDFVF=D3DFVF_XYZ|D3DFVF_TEX1;

//计算地形的灵活顶点

if（FAILED（m_pd3dDevice->

CreateVertexBuffer（m_nNumVertices*sizeof（SKYBOXVERTEX）,

D3DUSAGE_WRITEONLY,SKYBOXVERTEX:

FVF,D3DPOOL_MANAGED,&

m_pVertexBuf,0）））

returnFALSE;

SKYBOXVERTEX*pVertices=NULL;

m_pVertexBuf->

Lock（0,0,（void**）&

pVertices,0）;

intnIndex=0;

FLOATfAlpha=2.0f*D3DX_PI*nAlpha/360.0f;

//经度角转换为弧度表示

FLOATfBeta=2.0f*D3DX_PI*nBeta/360.0f;

//维度角转换为弧度表示

for（introw=0;

row<

m_nNumLongitudes+1;

row++）

for（intcol=0;

col<

m_nNumLatitudes+1;

col++）

//计算顶点的坐标

pVertices[nIndex]._x=fRadius*cosf（row*fBeta）*cosf（col*fAlpha）;

pVertices[nIndex]._y=fRadius*sinf（row*fBeta）;

pVertices[nIndex]._z=fRadius*cosf（row*fBeta）*sinf（col*fAlpha）;

//计算顶点的纹理坐标

pVertices[nIndex]._u=col*fAlpha/（2.0f*D3DX_PI）;

pVertices[nIndex]._v=row*fBeta/（D3DX_PI/2.0f）;

nIndex++;

对于半球面上的任意点A，并以该点为起始顶点的两个相邻三角形的顶点B、C、D点，它们的位置关系将如图所示。

pIndices[nIndex+0]=row*m_nVertsPerLongi+col;

pIndices[nIndex+1]=（row+1）*m_nVertsPerLongi+col;

pIndices[nIndex+2]=（row+1）*m_nVertsPerLongi+col+1;

pIndices[nIndex+3]=row*m_nVertsPerLongi+col;

pIndices[nIndex+4]=（row+1）*m_nVertsPerLongi+col+1;

pIndices[nIndex+5]=row*m_nVertsPerLongi+col+1;

nIndex+=6;

球形天空类定义：

CSkyBox.h

classCSkybox

LPDIRECT3DTEXTURE9m_pTexture;

LPDIRECT3DINDEXBUFFER9m_pIndexBuf;

LPDIRECT3DVERTEXBUFFER9m_pVertexBuf;

INTm_nNumLatitudes;

//维度的数目

INTm_nNumLongitudes;

//经度的数目

INTm_nVertsPerLati;

//每条维度上包含的顶点数

INTm_nVertsPerLongi;

//每条经度上包含的顶点数

INTm_nNumVertices;

//顶点总数

FLOATm_fSkyboxRadius;

//球形天空的半径

structSKYBOXVERTEX//球形天空的顶点结构

SKYBOXVERTEX（FLOATx,FLOATy,FLOATz,FLOATu,FLOATv）

CSkybox（IDirect3DDevice9*pd3dDevice）;

virtual~CSkybox（void）;

BOOLLoadSkybox（wchar_t*pTextureFile）;

//加载纹理

BOOLInitSkybox（INTnAlpha,INTnBeta,FLOATnRadius）;

//初始化球形天空

BOOLDrawSkybox（D3DXMATRIX*pMatWorld,BOOLbDrawFrame=FALSE）;

//绘制天空

球形天空类的实现SkyBox.cpp

SkyBox.h"

CSkyBox:

CSkyBox（IDirect3DDevice9*pd3dDevice）

m_pTexture=NULL;

m_pIndexBuf=NULL;

m_pVertexBuf=NULL;

m_nNumVertices=0;

m_nNumLatitudes=0;

m_nNumLongitudes=0;

m_nVertsPerLongi=0;

m_nVertsPerLati=0;

m_fSkyBoxRadius=0;

~CSkyBox（void）

if（m_pIndexBuf!

=NULL）

m_pIndexBuf->

Release（）;

if（m_pTexture!

m_pTexture->

if（m_pVertexBuf!

m_pVertexBuf->

BOOLCSkyBox:

LoadSkyBox（wchar_t*pTextureFile）

//加载天空纹理

if（FAILED（D3DXCreateTextureFromFile（m_pd3dDevice,pTextureFile,&

m_pTexture）））

returnTRUE;

InitSkyBox（INTnAlpha,INTnBeta,FLOATfRadius）

m_fSkyBoxRadius=fRadius;

//半球体的半径

m_nNumLatitudes=360/nAlpha;

//维度线的条数

m_nNumLongitudes=90/nBeta;

//经度线的条数

m_nVertsPerLongi=m_nNumLatitudes+1;

//每条经度线上的顶点数

m_nVertsPerLati=m_nNumLongitudes+1;

m_nNumVertices=m_nVertsPerLati*m_nVertsPerLongi;

//计算天空的灵活顶点

CreateVertexBuffer（m_nNumVertices*sizeof（SkyBoxVERTEX）,

D3DUSAGE_WRITEONLY,SkyBoxVERTEX:

FVF,D3DPOOL_MANAGED,&

m_pVertexBuf,0）））

SkyBoxVERTEX*pVertices=NULL;

m_pVertexBuf->

intnIndex=0;

FLOATfAlpha=2.0f*D3DX_PI*nAlpha/360.0f;

FLOATfBeta=2.0f*D3DX_PI*nBeta/360.0f;

for（introw=0;

Unlock（