DirextX编程

开发平台：
Visual C++

Terrain.cpp：源码内容
							#include "zfxd3dUtility.h"
#include "terrain.h"
#include ".terrain.h"
#define MINELEV 0.0f
CZFXTerrain::CZFXTerrain(void)
{
	m_iWidth=0;
	m_iHeight=0;
	m_pVB=NULL;
	m_pIB=NULL;
	m_pTexture = NULL;
}
CZFXTerrain::~CZFXTerrain(void)
{
	SAFE_RELEASE(m_pVB);
	SAFE_RELEASE(m_pIB);
	SAFE_RELEASE(m_pTexture);
}
bool CZFXTerrain::RenderTerrain( LPDIRECT3DDEVICE9 pd3dDevice, D3DFILLMODE Flag)
{
	if( NULL == m_pVB )
	{
		MessageBox( NULL, "地形未创建或未成功创建", "渲染地形失败", MB_OK );
		return false;
	}
    // set material
	D3DMATERIAL9 material;
	ZeroMemory( &material, sizeof(D3DMATERIAL9) );
	material.Ambient.r = material.Ambient.g = material.Ambient.b = material.Ambient.a = 1.0f;
	material.Diffuse.r = material.Diffuse.g = material.Diffuse.b = material.Diffuse.a = 1.0f;
	material.Specular.r = material.Specular.g = material.Specular.b = material.Specular.a = 1.0f;
	pd3dDevice->SetMaterial( &material );
	// set lighting
	D3DLIGHT9 light;
	ZeroMemory( &light, sizeof(light) );
	light.Type = D3DLIGHT_DIRECTIONAL;
	light.Diffuse.r = 0.5f;
	light.Diffuse.g = 0.5f;
	light.Diffuse.b = 0.5f;
	light.Diffuse.a = 0.5f;
	light.Direction.x = -3.0f; light.Direction.y = -3.0f; light.Direction.z = 0.0f;
	pd3dDevice->SetLight( 0, &light );
	pd3dDevice->LightEnable( 0, TRUE );
	pd3dDevice->SetRenderState( D3DRS_AMBIENT, 0xff444444 );
	// set render state
	pd3dDevice->SetRenderState(D3DRS_FILLMODE, Flag);
	// set texture
	pd3dDevice->SetTexture(0, m_pTexture);
	// Rendering
	pd3dDevice->SetFVF( D3DFVF_CUSTOMVERTEX );
	pd3dDevice->SetStreamSource( 0, m_pVB, 0, sizeof(CUSTOMVERTEX) );
	pd3dDevice->SetIndices(m_pIB);
	pd3dDevice->DrawIndexedPrimitive( D3DPT_TRIANGLELIST, // PrimitiveType
		0,                  // BaseVertexIndex
		0,                  // MinIndex
		m_iWidth*m_iHeight,                  // NumVertices
		0,                  // StartIndex
		2*(m_iWidth - 1) * (m_iHeight -1) ); // PrimitiveCount
	return true;
}
void CZFXTerrain::OnDestroyDevice()
{
	SAFE_RELEASE(m_pVB);
	SAFE_RELEASE(m_pIB);
	SAFE_RELEASE(m_pTexture);
}
bool CZFXTerrain::CreateTerrain( LPDIRECT3DDEVICE9 pd3dDevice, int iWidth, int iHeight, float fWidth, float fHeight, 
								float height[][200], LPCTSTR strTexFileName )
{
	m_iWidth  = iWidth;
	m_iHeight = iHeight;
	// 创建纹理
	if(strTexFileName != NULL)
	{
		if( FAILED( D3DXCreateTextureFromFile( pd3dDevice, strTexFileName, &m_pTexture )))
		{
			m_pTexture = NULL;
		}
	}
	else
	{
		m_pTexture = NULL;
	}
	CUSTOMVERTEX* vertices;
	vertices = new CUSTOMVERTEX[iWidth * iHeight];
	//// 调试用语句
	//float fMin = 100.0f;
	//float fMax = -100.0f;
	//// 调试用语句end
	for(int i=0;i<iHeight;i++)
	{
		for(int j=0;j<iWidth;j++)
		{
			//求出顶点的位置
			float x = (((float)(j-iWidth/2))*fWidth)/(float)iWidth;
			float y = (float)(height[i][j]-MINELEV)/2.0f;
			//// 调试用语句
			//if( y < -20.0f )
			//	fMin = y;
			//if( y < fMin )
			//	fMin = y;
			//if( y > fMax )
			//	fMax = y;
			//// 调试用语句end
			float z = (((float)(i-iHeight/2))*fHeight)/(float)iHeight;
			vertices[i*(iWidth)+j].position = D3DXVECTOR3( x, y, z);
			//确定顶点的颜色
			vertices[i*(iWidth)+j].color = 0xffffffff;
			//求该点的法线向量,两向量叉乘
			//     / (i+1,j)
			//     ||
			//     ||<----(i,j+1)
			//    (i,j)
			float deltaHeight1, deltaHeight2;
			if(i<iHeight-1)
				deltaHeight1 = float(height[i][j]-height[i+1][j]);
			else
				deltaHeight1 = float(height[i-1][j]-height[i][j]);
			if(j<iWidth-1)
				deltaHeight2 = float(height[i][j+1]-height[i][j]);
			else
				deltaHeight2 = float(height[i][j]-height[i][j-1]);
			D3DXVECTOR3 vec1( -1.0f, 0.0f, deltaHeight1 );
			D3DXVECTOR3 vec2(  0.0f, 1.0f, deltaHeight2 );
			D3DXVec3Cross( &vertices[i*(iWidth)+j].normal, &vec1, &vec2 );
		//	ASSERT(vertices[i*(iHeight+1)+j].normal
			//得到顶点的纹理坐标
			vertices[i*(iWidth)+j].tu = (float)i*20.0f/(float)iWidth;
			vertices[i*(iWidth)+j].tv = (float)j*20.0f/(float)iHeight;
		}
	}
	// WORD的大小仅限于256*256，所以当indices数组中某元素大于256*256时，将发生溢出
	// 相应的，创建索引缓冲的时候，D3DFMT_INDEX16需替换成D3DFMT_INDEX32
    DWORD* indices;
	indices=new DWORD[6*(iWidth-1)*(iHeight-1)];
	int baseIndex = 0;
	for(DWORD i=0;i<(DWORD)iHeight-1;i++)
	{
		for(DWORD j=0;j<(DWORD)iWidth-1;j++)
		{
			indices[baseIndex]=i*(DWORD)iWidth+j;
			indices[baseIndex+1]=(i+1)*(DWORD)iWidth+j;
            indices[baseIndex+2]=(i+1)*(DWORD)iWidth+j+1;
            indices[baseIndex+3]=i*(DWORD)iWidth+j;
            indices[baseIndex+4]=(i+1)*(DWORD)iWidth+j+1;
            indices[baseIndex+5]=i*(DWORD)iWidth+j+1;
			baseIndex+=6;
		}
	}
    if( FAILED( pd3dDevice->CreateIndexBuffer( 6*(iHeight-1)*(iWidth-1)*sizeof(DWORD),
           D3DUSAGE_WRITEONLY, D3DFMT_INDEX32, D3DPOOL_MANAGED, 
	       &m_pIB, NULL ) ) )
    return false;
	if( FAILED( pd3dDevice->CreateVertexBuffer( (iHeight)*(iWidth)*sizeof(CUSTOMVERTEX),
         0 /*Usage*/, D3DFVF_CUSTOMVERTEX, D3DPOOL_MANAGED, &m_pVB, NULL )))
    return  false;
	VOID* pVertices;
	
	if( FAILED( m_pVB->Lock( 0, (iHeight)*(iWidth)*sizeof( CUSTOMVERTEX ), (void**)&pVertices, 0 ) ) )
		return false;
      memcpy( pVertices, vertices, (iHeight)*(iWidth)*sizeof( CUSTOMVERTEX ) );
	 m_pVB->Unlock();
	VOID* pIndices;
	if( FAILED( m_pIB->Lock( 
		0,                 // Fill from start of the buffer
		6*(iHeight-1)*(iWidth-1)*sizeof(DWORD),// Size of the data to load
		(void**)&pIndices,  // Returned index data
		0 ) )   )         // Send default flags to the lock
	{
		//SAFE_RELEASE(m_pIB);
		return false;
	}
	memcpy( pIndices, indices, 6*(iHeight-1)*(iWidth-1)*sizeof(DWORD) );
	m_pIB->Unlock();
	delete [] vertices;
	delete [] indices;
	return false;
}

						