OpenGL

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Visual C++

rwrgb.txt：源码内容
							From cyy Wed Aug 11 10:03:15 1999
Return-Path: <cyy>
Received: by ox (SMI-8.6/SMI-SVR4)
	id KAA00559; Wed, 11 Aug 1999 10:03:15 +0900
Date: Wed, 11 Aug 1999 10:03:15 +0900
From: cyy (Chen Yanyun)
Message-Id: <199908110103.KAA00559@ox>
To: zhx
Content-Length: 6251
X-Lines: 258
Status: RO
/*==============================================================*
 |	function:	write_bmp				|
 *==============================================================*/
void	write_bmp(char *filename)
{       
	int	viewx,viewy;
    int	x,y,i,j;
    int	Xlen, Ylen; 
    GLint	port[4];
	unsigned char pcrgb;
	BITMAPFILEHEADER head;BITMAPINFOHEADER info;
	FILE *fp;
	unsigned short *rbuf;
	unsigned short *gbuf;
	unsigned short *bbuf;
	unsigned char *pbuf;
        
	glGetIntegerv(GL_VIEWPORT,port);
	viewx	= port[2]-port[0];
	viewy	= port[3]-port[1]; 
    Xlen	= viewx;
    Ylen	= viewy;
        
	pbuf	= (unsigned char *) malloc(viewx*viewy*3);
	rbuf	= (unsigned short *)malloc(Xlen*sizeof(short));
	gbuf	= (unsigned short *)malloc(Xlen*sizeof(short));
	bbuf	= (unsigned short *)malloc(Xlen*sizeof(short));
	if ( (pbuf == NULL)||(rbuf == NULL)||(gbuf == NULL)||(bbuf == NULL) )
	{
			printf("Malloc bbuf mamory failure n");
			exit(0);
	}
	glReadPixels(0,0,viewx,viewy,GL_RGB,GL_UNSIGNED_BYTE,pbuf);
	fp=fopen(filename,"wb");
	if(fp==NULL) {printf("Can't Create New Filen");exit(-1);}
	head.bfType=0x4d42;
	head.bfSize=sizeof(BITMAPFILEHEADER)+sizeof(BITMAPINFOHEADER)+
	Xlen*Ylen*3; 
	head.bfReserved1=0;head.bfReserved2=0;
	head.bfOffBits=sizeof(BITMAPFILEHEADER)+sizeof(BITMAPINFOHEADER);
	info.biSize=sizeof(BITMAPINFOHEADER);
	info.biWidth=Xlen;
	info.biHeight=Ylen;
	info.biPlanes=1; 
	info.biBitCount=24;
    info.biCompression=0; 
	info.biSizeImage=0; 
	info.biXPelsPerMeter=0; 
    info.biYPelsPerMeter=0; 
    info.biClrUsed=0; 
    info.biClrImportant=0;
	fwrite(&head,sizeof(BITMAPFILEHEADER),1,fp);
	fwrite(&info,sizeof(BITMAPINFOHEADER),1,fp);
	i=0;
	for( y=0; y<Ylen; y++)
	{
		for(x=0; x<Xlen; x++)
		{
			rbuf[x] = (short)(pbuf[(i+x)*3]);
			gbuf[x] = (short)(pbuf[(i+x)*3+1]);
			bbuf[x] = (short)(pbuf[(i+x)*3+2]);
		}
		i += Xlen;
		for(j=0;j<Xlen;j++)
		{	pcrgb=(unsigned char)bbuf[j];
			fwrite(&pcrgb,1,1,fp);
			pcrgb=(unsigned char)gbuf[j];
			fwrite(&pcrgb,1,1,fp);
			pcrgb=(unsigned char)rbuf[j];
			fwrite(&pcrgb,1,1,fp);
		}
		j=Xlen;
		if(j%4!=0)	j=4-j%4;
		else		j=0;
		pcrgb=0;
		while(j>0)
		{	fwrite(&pcrgb,1,1,fp);
			j--;
		}/* this is because windows bmp's characteristic */
	}
	fclose(fp);
	free(pbuf);
	free(rbuf);
	free(gbuf);
	free(bbuf); 
}/*____write_bmp____*/
///////////////////////////////////////////////////////////////////
/*==============================================================*
 |	function:	OpenTexture				|
 *==============================================================*/
void	OpenTexture( char *fn )
{
#if platform==windowsnt
	BITMAPFILEHEADER head;BITMAPINFOHEADER info;
	unsigned char *ImageData,ddd;FILE *fp;
	int	 index;
	int	i,j,rslp, rslx, rsly;
	fp=fopen(fn,"rb");
	if(fp==NULL) {printf("Can't Create New Filen");exit(-1);}
	
	fread(&head,sizeof(BITMAPFILEHEADER),1,fp);
	fread(&info,sizeof(BITMAPINFOHEADER),1,fp);
	rslx=info.biWidth;
	rsly=info.biHeight;		
	if(rslx%4!=0)	rslp=rslx+4-rslx%4;
	else			rslp=rslx;
	ImageData=(unsigned char *) malloc(rslp*rsly*3);
	if(ImageData==NULL){
		printf("Malloc ImageData mamory failure n");
		exit(0);
	}
	
	fread(ImageData,1,rslp*rsly*3,fp);
	
	rslp*=3;
	for(i=0;i<rsly;i++){
		index=i*rslp;
		for(j=0;j<rslx;j++){
			ddd=ImageData[index];
			ImageData[index]=ImageData[index+2];
			ImageData[index+2]=ddd;
			index+=3;
		}
	}
	fclose(fp);
#else
	IMAGE		*image;
	unsigned short	srcx, srcy, srcz,
			x, y;
	unsigned int	i, rslp, srcp, srcp2, rslx, rsly;
	unsigned short	*rbuf, *gbuf, *bbuf;
	float		daltarx, daltary;
	char		*SImageData, *ImageData;
	/*
	 * load a image
	 */
	if((image = iopen(fn, "r", RLE(1), 3, srcx, srcy, 3)) == NULL)
	{	printf("n Can not open %sn", fn);	return;	}
	
	srcx = image->xsize;
	srcy = image->ysize;
	srcz = image->zsize;
	if( srcz < 3 )
	{	printf("n Can not read %sn", fn);	return;	}		
	SImageData = (unsigned char *)malloc(srcx*srcy*3);
	if(SImageData==NULL){
			printf("Malloc SImageData mamory failure n");
			exit(0);
	}
	rbuf = (unsigned short*)malloc(srcx*sizeof(short));
	if(rbuf==NULL){
			printf("Malloc rbuf mamory failure n");
			exit(0);
	}
  	gbuf = (unsigned short*)malloc(srcx*sizeof(short));
	if(gbuf==NULL){
			printf("Malloc gbuf mamory failure n");
			exit(0);
	}
  	bbuf = (unsigned short*)malloc(srcx*sizeof(short));
	if(bbuf==NULL){
			printf("Malloc bbuf mamory failure n");
			exit(0);
	}
	
	i = 0;
  	for( y=0; y<srcy; y++)
	{
     		getrow(image, rbuf,y,0);
     		getrow(image, gbuf,y,1);
     		getrow(image, bbuf,y,2);
     		for(x=0; x<srcx; x++)
		{
        		SImageData[i] = (unsigned char)rbuf[x]; i++;
        		SImageData[i] = (unsigned char)gbuf[x]; i++;
        		SImageData[i] = (unsigned char)bbuf[x]; i++;
       		}
	}
	iclose(image);
	/*
	 * Texture size
	 */ 
	rslx = rsly = 1;
	while( (rslx<<1) <= srcx ) rslx <<= 1;
	while( (rsly<<1) <= srcy ) rsly <<= 1;
	ImageData = (unsigned char *)malloc( rslx * rsly * 3 );
	if(ImageData==NULL){
			printf("Malloc ImageData mamory failure n");
			exit(0);
	}
	/*
	 * Calc. daltar
	 */
	daltarx = (float)srcx/(float)rslx;
	daltary = (float)srcy/(float)rsly;
	/*
	 * map source picture to texture-image
	 */
	rslp = srcp = 0;
	for( y = 0; y < rsly; y++ )
	{
		srcp2 = srcx * 3 * (int)( daltary*y );
		rslp = y * rslx * 3;
		for( x = 0; x < rslx; x ++ )
		{
			ImageData[ rslp ]	= SImageData[ srcp ];
			ImageData[ rslp + 1 ]	= SImageData[ srcp + 1 ];
			ImageData[ rslp + 2 ]	= SImageData[ srcp + 2 ];
			rslp += 3;
			srcp  = srcp2 + 3 * (int)((x+1) * daltarx);
		}
	}
	/*
	 * free memory
	 */
	free( rbuf );
	free( gbuf );
	free( bbuf ); 
	free( SImageData );
#endif
	
	/*
	 * Enable 2D texture
	 */
	glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
	glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE);
	glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
	glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
	glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
	glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
	glTexImage2D (	GL_TEXTURE_2D, 0, 3, rslx, rsly,
			0,GL_RGB, GL_UNSIGNED_BYTE, ImageData );
	glEnable(GL_TEXTURE_2D);
	
	free( ImageData );
}/*____Open Texture____*/
////////////////////////////////////////////////////////////////

						