nuclear@0: /*
nuclear@0: 256-color 3D graphics hack for real-mode DOS.
nuclear@0: Copyright (C) 2011  John Tsiombikas <nuclear@member.fsf.org>
nuclear@0: 
nuclear@0: This program is free software: you can redistribute it and/or modify
nuclear@0: it under the terms of the GNU General Public License as published by
nuclear@0: the Free Software Foundation, either version 3 of the License, or
nuclear@0: (at your option) any later version.
nuclear@0: 
nuclear@0: This program is distributed in the hope that it will be useful,
nuclear@0: but WITHOUT ANY WARRANTY; without even the implied warranty of
nuclear@0: MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
nuclear@0: GNU General Public License for more details.
nuclear@0: 
nuclear@0: You should have received a copy of the GNU General Public License
nuclear@0: along with this program.  If not, see <http://www.gnu.org/licenses/>.
nuclear@0: */
nuclear@0: 
nuclear@0: #include <stdio.h>
nuclear@0: #include <string.h>
nuclear@0: #include <stdlib.h>
nuclear@0: #include "texture.h"
nuclear@0: #include "palman.h"
nuclear@0: 
nuclear@0: struct texture *load_texture(const char *fname)
nuclear@0: {
nuclear@0: 	long i, num_pixels;
nuclear@0: 	struct texture *tex;
nuclear@0: 	long fpos;
nuclear@0: 
nuclear@0: 	if(!(tex = malloc(sizeof *tex))) {
nuclear@0: 		return 0;
nuclear@0: 	}
nuclear@0: 	memset(tex, 0, sizeof *tex);
nuclear@0: 
nuclear@0: 	if(!(tex->file = fopen(fname, "rb"))) {
nuclear@0: 		fprintf(stderr, "failed to open texture: %s\n", fname);
nuclear@0: 		free_texture(tex);
nuclear@0: 		return 0;
nuclear@0: 	}
nuclear@0: 	if(fscanf(tex->file, "P6 %d %d 255 ", &tex->width, &tex->height) != 2) {
nuclear@0: 		fprintf(stderr, "invalid pixmap: %s\n", fname);
nuclear@0: 		free_texture(tex);
nuclear@0: 		return 0;
nuclear@0: 	}
nuclear@0: 	fpos = ftell(tex->file);
nuclear@0: 
nuclear@0: 	num_pixels = tex->width * tex->height;
nuclear@0: 	for(i=0; i<num_pixels; i++) {
nuclear@0: 		int r, g, b;
nuclear@0: 
nuclear@0: 		r = fgetc(tex->file);
nuclear@0: 		g = fgetc(tex->file);
nuclear@0: 		b = fgetc(tex->file);
nuclear@0: 
nuclear@0: 		if(feof(tex->file)) {
nuclear@0: 			fprintf(stderr, "unexpected EOF while reading: %s\n", fname);
nuclear@0: 			free_texture(tex);
nuclear@0: 			return 0;
nuclear@0: 		}
nuclear@0: 
nuclear@0: 		if(palm_color_index(r, g, b) == -1) {
nuclear@0: 			palm_add_color(r, g, b);
nuclear@0: 		}
nuclear@0: 	}
nuclear@0: 	fseek(tex->file, fpos, SEEK_SET);
nuclear@0: 	return tex;
nuclear@0: }
nuclear@0: 
nuclear@0: void free_texture(struct texture *tex)
nuclear@0: {
nuclear@0: 	if(tex) {
nuclear@0: 		if(tex->file) {
nuclear@0: 			fclose(tex->file);
nuclear@0: 		}
nuclear@0: 		free(tex->pixels);
nuclear@0: 		free(tex);
nuclear@0: 	}
nuclear@0: }
nuclear@0: 
nuclear@0: unsigned char *get_texture_pixels(struct texture *tex)
nuclear@0: {
nuclear@0: 	if(!tex->pixels && tex->file) {
nuclear@0: 		long i, num_pixels = tex->width * tex->height;
nuclear@0: 
nuclear@0: 		if(!(tex->pixels = malloc(num_pixels))) {
nuclear@0: 			return 0;
nuclear@0: 		}
nuclear@0: 
nuclear@0: 		for(i=0; i<num_pixels; i++) {
nuclear@0: 			int r, g, b, base;
nuclear@0: 
nuclear@0: 			r = fgetc(tex->file);
nuclear@0: 			g = fgetc(tex->file);
nuclear@0: 			b = fgetc(tex->file);
nuclear@0: 
nuclear@0: 			if((base = palm_color_base(r, g, b)) == -1) {
nuclear@0: 				base = 0;
nuclear@0: 			}
nuclear@0: 			tex->pixels[i] = base;
nuclear@0: 		}
nuclear@0: 
nuclear@0: 		fclose(tex->file);
nuclear@0: 		tex->file = 0;
nuclear@0: 	}
nuclear@0: 
nuclear@0: 	return tex->pixels;
nuclear@0: }
nuclear@0: 
nuclear@0: struct texture *tex_gen_checker(int xsz, int ysz, int ush, int vsh, int c1, int c2)
nuclear@0: {
nuclear@0: 	int i, j;
nuclear@0: 	struct texture *tex;
nuclear@0: 	unsigned char *pptr;
nuclear@0: 
nuclear@0: 	if(!(tex = malloc(sizeof *tex))) {
nuclear@0: 		return 0;
nuclear@0: 	}
nuclear@0: 	memset(tex, 0, sizeof *tex);
nuclear@0: 
nuclear@0: 	if(!(tex->pixels = malloc(xsz * ysz))) {
nuclear@0: 		free(tex);
nuclear@0: 		return 0;
nuclear@0: 	}
nuclear@0: 	tex->width = xsz;
nuclear@0: 	tex->height = ysz;
nuclear@0: 
nuclear@0: 	pptr = tex->pixels;
nuclear@0: 	for(i=0; i<ysz; i++) {
nuclear@0: 		for(j=0; j<xsz; j++) {
nuclear@0: 			int c = ((i >> vsh) & 1) == ((j >> ush) & 1) ? c1 : c2;
nuclear@0: 			*pptr++ = c;
nuclear@0: 		}
nuclear@0: 	}
nuclear@0: 	return tex;
nuclear@0: }