mytexture.cpp

粒子系统模拟心动周期血流

// MyTexture.cpp: implementation of the CMyTexture class.
//
//////////////////////////////////////////////////////////////////////

#include "stdafx.h"
#include "MyFountain.h"
#include "MyTexture.h"

#ifdef _DEBUG
#undef THIS_FILE
static char THIS_FILE[]=__FILE__;
#define new DEBUG_NEW
#endif

//////////////////////////////////////////////////////////////////////
// Construction/Destruction
//////////////////////////////////////////////////////////////////////

CMyTexture::CMyTexture()
{

}

CMyTexture::~CMyTexture()
{

}

void CMyTexture::bwtorgba(unsigned char *b,unsigned char *l,int n)
{
    while(n--)
	{
	l[0] = *b;
	l[1] = *b;
	l[2] = *b;
	l[3] = 0xff;
	l += 4; b++;
    }
}

void CMyTexture::latorgba(unsigned char *b, unsigned char *a,unsigned char *l,int n) 
{
    while(n--) 
	{
	l[0] = *b;
	l[1] = *b;
	l[2] = *b;
	l[3] = *a;
	l += 4; b++; a++;
    }
}

void CMyTexture::rgbtorgba(unsigned char *r,unsigned char *g,unsigned char *b,unsigned char *l,int n) 
{
    while(n--) 
	{
	l[0] = r[0];
	l[1] = g[0];
	l[2] = b[0];
	l[3] = 0xff;
	l += 4; r++; g++; b++;
    }
}

void CMyTexture::rgbatorgba(unsigned char *r,unsigned char *g,unsigned char *b,unsigned char *a,unsigned char *l,int n) 
{
    while(n--) 
	{
	l[0] = r[0];
	l[1] = g[0];
	l[2] = b[0];
	l[3] = a[0];
        l += 4; r++; g++; b++; a++;
    }
}


void CMyTexture::ConvertShort(unsigned short *array, long length) 
{
    unsigned b1, b2;
    unsigned char *ptr;

    ptr = (unsigned char *)array;
    while (length--) 
	{
	b1 = *ptr++;
	b2 = *ptr++;
	*array++ = (b1 << 8) | (b2);
    }
}

void CMyTexture::ConvertLong(unsigned *array, long length) 
{
    unsigned b1, b2, b3, b4;
    unsigned char *ptr;

    ptr = (unsigned char *)array;
    while (length--) {
	b1 = *ptr++;
	b2 = *ptr++;
	b3 = *ptr++;
	b4 = *ptr++;
	*array++ = (b1 << 24) | (b2 << 16) | (b3 << 8) | (b4);
    }
}

ImageRec * CMyTexture::ImageOpen(const char *fileName)
{
    union {
	int testWord;
	char testByte[4];
    } endianTest;
    ImageRec *image;
    int swapFlag;
    int x;

    endianTest.testWord = 1;
    if (endianTest.testByte[0] == 1) {
	swapFlag = 1;
    } else {
	swapFlag = 0;
    }

    image = (ImageRec *)malloc(sizeof(ImageRec));
    if (image == NULL) {
	fprintf(stderr, "Out of memory!\n");
	exit(1);
    }
    if ((image->file = fopen(fileName, "rb")) == NULL) {
	perror(fileName);
	exit(1);
    }

    fread(image, 1, 12, image->file);

    if (swapFlag) {
	ConvertShort(&image->imagic, 6);
    }

    image->tmp = (unsigned char *)malloc(image->xsize*256);
    image->tmpR = (unsigned char *)malloc(image->xsize*256);
    image->tmpG = (unsigned char *)malloc(image->xsize*256);
    image->tmpB = (unsigned char *)malloc(image->xsize*256);
    if (image->tmp == NULL || image->tmpR == NULL || image->tmpG == NULL ||
	image->tmpB == NULL) {
	fprintf(stderr, "Out of memory!\n");
	exit(1);
    }

    if ((image->type & 0xFF00) == 0x0100) {
	x = image->ysize * image->zsize * sizeof(unsigned);
	image->rowStart = (unsigned *)malloc(x);
	image->rowSize = (int *)malloc(x);
	if (image->rowStart == NULL || image->rowSize == NULL) {
	    fprintf(stderr, "Out of memory!\n");
	    exit(1);
	}
	image->rleEnd = 512 + (2 * x);
	fseek(image->file, 512, SEEK_SET);
	fread(image->rowStart, 1, x, image->file);
	fread(image->rowSize, 1, x, image->file);
	if (swapFlag) {
	    ConvertLong(image->rowStart, x/(int)sizeof(unsigned));
	    ConvertLong((unsigned *)image->rowSize, x/(int)sizeof(int));
	}
    } else {
	image->rowStart = NULL;
	image->rowSize = NULL;
    }
    return image;
}

void CMyTexture::ImageClose(ImageRec *image) 
{
    fclose(image->file);
    free(image->tmp);
    free(image->tmpR);
    free(image->tmpG);
    free(image->tmpB);
    free(image->rowSize);
    free(image->rowStart);
    free(image);
}

void CMyTexture::ImageGetRow(ImageRec *image, unsigned char *buf, int y, int z) 
{
    unsigned char *iPtr, *oPtr, pixel;
    int count;

    if ((image->type & 0xFF00) == 0x0100) {
	fseek(image->file, (long)image->rowStart[y+z*image->ysize], SEEK_SET);
	fread(image->tmp, 1, (unsigned int)image->rowSize[y+z*image->ysize],
	      image->file);

	iPtr = image->tmp;
	oPtr = buf;
	for (;;) {
	    pixel = *iPtr++;
	    count = (int)(pixel & 0x7F);
	    if (!count) {
		return;
	    }
	    if (pixel & 0x80) {
		while (count--) {
		    *oPtr++ = *iPtr++;
		}
	    } else {
		pixel = *iPtr++;
		while (count--) {
		    *oPtr++ = pixel;
		}
	    }
	}
    } else {
	fseek(image->file, 512+(y*image->xsize)+(z*image->xsize*image->ysize),
	      SEEK_SET);
	fread(buf, 1, image->xsize, image->file);
    }
}

unsigned * CMyTexture::read_texture(char *name, int *width, int *height, int *components) 
{
    unsigned *base, *lptr;
    unsigned char *rbuf, *gbuf, *bbuf, *abuf;
    ImageRec *image;
    int y;

    image = ImageOpen(name);
    
    if(!image)
	return NULL;
    (*width)=image->xsize;
    (*height)=image->ysize;
    (*components)=image->zsize;
    base = (unsigned *)malloc(image->xsize*image->ysize*sizeof(unsigned));
    rbuf = (unsigned char *)malloc(image->xsize*sizeof(unsigned char));
    gbuf = (unsigned char *)malloc(image->xsize*sizeof(unsigned char));
    bbuf = (unsigned char *)malloc(image->xsize*sizeof(unsigned char));
    abuf = (unsigned char *)malloc(image->xsize*sizeof(unsigned char));
    if(!base || !rbuf || !gbuf || !bbuf)
      return NULL;
    lptr = base;
    for(y=0; y<image->ysize; y++) {
	if(image->zsize>=4) {
	    ImageGetRow(image,rbuf,y,0);
	    ImageGetRow(image,gbuf,y,1);
	    ImageGetRow(image,bbuf,y,2);
	    ImageGetRow(image,abuf,y,3);
	    rgbatorgba(rbuf,gbuf,bbuf,abuf,(unsigned char *)lptr,image->xsize);
	    lptr += image->xsize;
	} else if(image->zsize==3) {
	    ImageGetRow(image,rbuf,y,0);
	    ImageGetRow(image,gbuf,y,1);
	    ImageGetRow(image,bbuf,y,2);
	    rgbtorgba(rbuf,gbuf,bbuf,(unsigned char *)lptr,image->xsize);
	    lptr += image->xsize;
	} else if(image->zsize==2) {
	    ImageGetRow(image,rbuf,y,0);
	    ImageGetRow(image,abuf,y,1);
	    latorgba(rbuf,abuf,(unsigned char *)lptr,image->xsize);
	    lptr += image->xsize;
	} else {
	    ImageGetRow(image,rbuf,y,0);
	    bwtorgba(rbuf,(unsigned char *)lptr,image->xsize);
	    lptr += image->xsize;
	}
    }
    ImageClose(image);
    free(rbuf);
    free(gbuf);
    free(bbuf);
    free(abuf);

    return (unsigned *) base;
}