#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <GL/glut.h>
typedef struct _ImageRec {
unsigned short imagic;
unsigned short type;
unsigned short dim;
unsigned short xsize, ysize, zsize;
unsigned int min, max;
unsigned int wasteBytes;
char name[80];
unsigned long colorMap;
FILE *file;
unsigned char *tmp;
unsigned long rleEnd;
unsigned int *rowStart;
int *rowSize;
} ImageRec;
void
rgbtorgb(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; r++; g++; b++;
}
}
static void
ConvertShort(unsigned short *array, unsigned int length) {
unsigned short b1, b2;
unsigned char *ptr;
ptr = (unsigned char *)array;
while (length--) {
b1 = *ptr++;
b2 = *ptr++;
*array++ = (b1 << 8) | (b2);
}
}
static void
ConvertUint(unsigned *array, unsigned int length) {
unsigned int 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);
}
}
static ImageRec *ImageOpen(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) {
return NULL;
}
fread(image, 1, 12, image->file);
if (swapFlag) {
ConvertShort(&image->imagic, 6);
}
image->tmp = (unsigned char *)malloc(image->xsize*256);
if (image->tmp == NULL) {
fprintf(stderr, "\nOut of memory!\n");
exit(1);
}
if ((image->type & 0xFF00) == 0x0100) {
x = image->ysize * image->zsize * (int) sizeof(unsigned);
image->rowStart = (unsigned *)malloc(x);
image->rowSize = (int *)malloc(x);
if (image->rowStart == NULL || image->rowSize == NULL) {
fprintf(stderr, "\nOut 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) {
ConvertUint(image->rowStart, x/(int) sizeof(unsigned));
ConvertUint((unsigned *)image->rowSize, x/(int) sizeof(int));
}
}
return image;
}
static void
ImageClose(ImageRec *image) {
fclose(image->file);
free(image->tmp);
free(image);
}
static void
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);
}
}
GLubyte *
read_alpha_texture(char *name, int *width, int *height)
{
unsigned char *base, *lptr;
ImageRec *image;
int y;
image = ImageOpen(name);
if(!image) {
return NULL;
}
(*width)=image->xsize;
(*height)=image->ysize;
if (image->zsize != 1) {
ImageClose(image);
return NULL;
}
base = (unsigned char *)malloc(image->xsize*image->ysize*sizeof(unsigned char));
lptr = base;
for(y=0; y<image->ysize; y++) {
ImageGetRow(image,lptr,y,0);
lptr += image->xsize;
}
ImageClose(image);
return (unsigned char *) base;
}
GLubyte *
read_rgb_texture(char *name, int *width, int *height)
{
unsigned char *base, *ptr;
unsigned char *rbuf, *gbuf, *bbuf, *abuf;
ImageRec *image;
int y;
image = ImageOpen(name);
if(!image)
return NULL;
(*width)=image->xsize;
(*height)=image->ysize;
if (image->zsize != 3 && image->zsize != 4) {
ImageClose(image);
return NULL;
}
base = (unsigned char*)malloc(image->xsize*image->ysize*sizeof(unsigned int)*3);
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 || !abuf) {
if (base) free(base);
if (rbuf) free(rbuf);
if (gbuf) free(gbuf);
if (bbuf) free(bbuf);
if (abuf) free(abuf);
return NULL;
}
ptr = 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);
rgbtorgb(rbuf,gbuf,bbuf,ptr,image->xsize);
ptr += (image->xsize * 3);
} else {
ImageGetRow(image,rbuf,y,0);
ImageGetRow(image,gbuf,y,1);
ImageGetRow(image,bbuf,y,2);
rgbtorgb(rbuf,gbuf,bbuf,ptr,image->xsize);
ptr += (image->xsize * 3);
}
}
ImageClose(image);
free(rbuf);
free(gbuf);
free(bbuf);
free(abuf);
return (GLubyte *) base;
}
int main(int argc, char **argv)
{
int width, height;
GLubyte *data;
char buff[32];
int n;
FILE *fo;
if (argc != 3)
{
fprintf(stderr, "usage: %s <infile.rgb> <outfile.p6>\n", argv[0]);
return 1;
}
data = read_rgb_texture(argv[1], &width, &height);
n = sprintf(buff, "P6\n%d %d\n255\n", width, height);
if ((fo = fopen(argv[2], "wb")) == NULL) {
fprintf(stderr, "Cannot open output file!\n");
exit(1);
}
fwrite(buff, n, 1, fo);
fwrite(data, width * 3, height, fo);
fclose(fo);
return 0;
}