nuclear@4: #include <stdio.h>
nuclear@4: #include <stdlib.h>
nuclear@4: #include <string.h>
nuclear@4: #include <errno.h>
nuclear@4: #include "image.h"
nuclear@4: 
nuclear@4: #define LOADFAIL(f, m)	fprintf(stderr, "failed to load image: %s: %s\n", f, m)
nuclear@4: 
nuclear@4: int load_image(struct image *img, const char *fname)
nuclear@4: {
nuclear@4: 	static const char *magic = "TILEIMAG";
nuclear@4: 	FILE *fp;
nuclear@4: 	char sig[8];
nuclear@4: 
nuclear@4: 	if(!(fp = fopen(fname, "rb"))) {
nuclear@4: 		LOADFAIL(fname, strerror(errno));
nuclear@4: 		return -1;
nuclear@4: 	}
nuclear@4: 	if(fread(sig, sizeof sig, 1, fp) <= 0 || memcmp(sig, magic, 8) != 0) {
nuclear@4: 		LOADFAIL(fname, "corrupted or empty file");
nuclear@4: 		fclose(fp);
nuclear@4: 		return -1;
nuclear@4: 	}
nuclear@4: 	if(fread(&img->xsz, 4, 1, fp) <= 0 || fread(&img->ysz, 4, 1, fp) <= 0) {
nuclear@4: 		LOADFAIL(fname, "failed to read file header");
nuclear@4: 		fclose(fp);
nuclear@4: 		return -1;
nuclear@4: 	}
nuclear@4: 
nuclear@4: 	if(!(img->pixels = malloc(img->xsz * img->ysz))) {
nuclear@4: 		LOADFAIL(fname, "failed to allocate pixel buffer");
nuclear@4: 		fclose(fp);
nuclear@4: 		return -1;
nuclear@4: 	}
nuclear@4: 	if(fread(img->pixels, 1, img->xsz * img->ysz, fp) < img->xsz * img->ysz) {
nuclear@4: 		LOADFAIL(fname, "unexpected end of file while reading pixels");
nuclear@4: 		fclose(fp);
nuclear@4: 		return -1;
nuclear@4: 	}
nuclear@4: 	fclose(fp);
nuclear@4: 	return 0;
nuclear@4: }
nuclear@4: 
nuclear@4: void destroy_image(struct image *img)
nuclear@4: {
nuclear@4: 	if(img) {
nuclear@4: 		free(img->pixels);
nuclear@4: 		img->pixels = 0;
nuclear@4: 	}
nuclear@4: }
nuclear@4: 
nuclear@4: int load_palette(struct color *col, const char *fname)
nuclear@4: {
nuclear@4: 	FILE *fp;
nuclear@4: 	char buf[128];
nuclear@4: 	int nent = 0;
nuclear@4: 
nuclear@4: 	if(!(fp = fopen(fname, "r"))) {
nuclear@4: 		fprintf(stderr, "failed to open palette file: %s: %s\n", fname, strerror(errno));
nuclear@4: 		return -1;
nuclear@4: 	}
nuclear@4: 
nuclear@4: 	while(fgets(buf, sizeof buf, fp)) {
nuclear@4: 		char *endp, *line = buf;
nuclear@4: 		int r, g, b;
nuclear@4: 
nuclear@4: 		if(!line || !*line) continue;
nuclear@4: 
nuclear@4: 		if(*line == '#') {	/* hex html-like values */
nuclear@4: 			unsigned int val = strtol(line + 1, &endp, 16);
nuclear@4: 			if(endp == line) {
nuclear@4: 				fprintf(stderr, "unrecognized line \"%s\" in palette file: %s\n", line, fname);
nuclear@4: 				fclose(fp);
nuclear@4: 				return -1;
nuclear@4: 			}
nuclear@4: 
nuclear@4: 			r = (val >> 16) & 0xff;
nuclear@4: 			g = (val >> 8) & 0xff;
nuclear@4: 			b = val & 0xff;
nuclear@4: 		} else {
nuclear@4: 			fprintf(stderr, "unrecognized line \"%s\" in palette file: %s\n", line, fname);
nuclear@4: 			fclose(fp);
nuclear@4: 			return -1;
nuclear@4: 		}
nuclear@4: 
nuclear@4: 		if(nent >= 256) {
nuclear@4: 			fprintf(stderr, "palette file %s contains more than 256 entries ... skipping the rest\n", fname);
nuclear@4: 			break;
nuclear@4: 		}
nuclear@4: 
nuclear@4: 		col[nent].r = r;
nuclear@4: 		col[nent].g = g;
nuclear@4: 		col[nent].b = b;
nuclear@4: 		nent++;
nuclear@4: 	}
nuclear@4: 
nuclear@4: 	printf("loaded palette: %s (%d colors)\n", fname, nent);
nuclear@4: 
nuclear@4: 	fclose(fp);
nuclear@4: 	return nent;
nuclear@4: }
nuclear@4: 
nuclear@4: #define MIN(a, b)	((a) < (b) ? (a) : (b))
nuclear@4: #define MAX(a, b)	((a) > (b) ? (a) : (b))
nuclear@4: 
nuclear@4: void blitkey(struct image *destimg, int dstx, int dsty, struct image *srcimg, int key)
nuclear@4: {
nuclear@4: 	int srcx = 0, srcy = 0;
nuclear@4: 	int i, j, width, height;
nuclear@4: 	unsigned char *src, *dst;
nuclear@4: 
nuclear@4: 	if(dstx < 0) {
nuclear@4: 		srcx += -dstx;
nuclear@4: 		dstx = 0;
nuclear@4: 	}
nuclear@4: 	if(dsty < 0) {
nuclear@4: 		srcy += -dsty;
nuclear@4: 		dsty = 0;
nuclear@4: 	}
nuclear@4: 
nuclear@4: 	width = MIN(destimg->xsz - dstx, srcimg->xsz - srcx);
nuclear@4: 	height = MIN(destimg->ysz - dsty, srcimg->ysz - srcy);
nuclear@4: 
nuclear@4: 	if(width <= 0 || height <= 0) return;	/* ended up with a zero-area blit */
nuclear@4: 
nuclear@4: 	src = srcimg->pixels + srcy * srcimg->xsz + srcx;
nuclear@4: 	dst = destimg->pixels + dsty * destimg->xsz + dstx;
nuclear@4: 
nuclear@4: 	for(i=0; i<height; i++) {
nuclear@4: 		for(j=0; j<width; j++) {
nuclear@4: 			if(src[j] != key) {
nuclear@4: 				dst[j] = src[j];
nuclear@4: 			}
nuclear@4: 		}
nuclear@4: 		src += srcimg->xsz;
nuclear@4: 		dst += destimg->xsz;
nuclear@4: 	}
nuclear@4: }