/* texture.c - by David Blythe, SGI */ /* texload is a simplistic routine for reading an SGI .rgb image file. */ #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); /* Discard. */ 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); /* [dBorca] avoid LF to CRLF conversion */ 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; }