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 <string.h>
nuclear@0: #include "palman.h"
nuclear@0: 
nuclear@0: #define MAX_COLORS		256
nuclear@0: static struct palm_color colors[MAX_COLORS];
nuclear@0: static int base_index[MAX_COLORS];
nuclear@0: 
nuclear@0: static struct palm_color pal[MAX_COLORS];
nuclear@0: static unsigned int ncol, pcol;
nuclear@0: static int range;
nuclear@0: 
nuclear@0: void palm_clear(void)
nuclear@0: {
nuclear@0: 	ncol = 0;
nuclear@0: }
nuclear@0: 
nuclear@0: int palm_add_color(unsigned char r, unsigned char g, unsigned char b)
nuclear@0: {
nuclear@0: 	if(ncol >= MAX_COLORS) {
nuclear@0: 		return -1;
nuclear@0: 	}
nuclear@0: 	colors[ncol].r = r;
nuclear@0: 	colors[ncol].g = g;
nuclear@0: 	colors[ncol].b = b;
nuclear@0: 	ncol++;
nuclear@0: 	return 0;
nuclear@0: }
nuclear@0: 
nuclear@0: int palm_color_index(unsigned char r, unsigned char g, unsigned char b)
nuclear@0: {
nuclear@0: 	int i;
nuclear@0: 
nuclear@0: 	for(i=0; i<ncol; i++) {
nuclear@0: 		if(colors[i].r == r && colors[i].g == g && colors[i].b == b) {
nuclear@0: 			return i;
nuclear@0: 		}
nuclear@0: 	}
nuclear@0: 	return -1;
nuclear@0: }
nuclear@0: 
nuclear@0: /* TODO: build an octree */
nuclear@0: int palm_build(void)
nuclear@0: {
nuclear@0: 	int i, j;
nuclear@0: 
nuclear@0: 	if(!ncol) {
nuclear@0: 		return -1;
nuclear@0: 	}
nuclear@0: 
nuclear@0: 	/* gradient range for each color */
nuclear@0: 	range = MAX_COLORS / ncol;
nuclear@0: 
nuclear@0: 	if(range <= 1) {
nuclear@0: 		memcpy(pal, colors, ncol * sizeof *pal);
nuclear@0: 		return 0;
nuclear@0: 	}
nuclear@0: 	pcol = 0;
nuclear@0: 
nuclear@0: 	for(i=0; i<ncol; i++) {
nuclear@0: 		unsigned short r, g, b, dr, dg, db;
nuclear@0: 
nuclear@0: 		base_index[i] = pcol;
nuclear@0: 
nuclear@0: 		dr = ((unsigned short)colors[i].r << 8) / (range - 1);
nuclear@0: 		dg = ((unsigned short)colors[i].g << 8) / (range - 1);
nuclear@0: 		db = ((unsigned short)colors[i].b << 8) / (range - 1);
nuclear@0: 
nuclear@0: 		r = g = b = 0;
nuclear@0: 		for(j=0; j<range; j++) {
nuclear@0: 			pal[pcol].r = (unsigned char)(r >> 8);
nuclear@0: 			pal[pcol].g = (unsigned char)(g >> 8);
nuclear@0: 			pal[pcol].b = (unsigned char)(b >> 8);
nuclear@0: 			pcol++;
nuclear@0: 			r += dr;
nuclear@0: 			g += dg;
nuclear@0: 			b += db;
nuclear@0: 		}
nuclear@0: 	}
nuclear@0: 	return pcol;
nuclear@0: }
nuclear@0: 
nuclear@0: struct palm_color *palm_palette(void)
nuclear@0: {
nuclear@0: 	return pal;
nuclear@0: }
nuclear@0: 
nuclear@0: int palm_palette_size(void)
nuclear@0: {
nuclear@0: 	return pcol;
nuclear@0: }
nuclear@0: 
nuclear@0: 
nuclear@0: int palm_color_base(unsigned char r, unsigned char g, unsigned char b)
nuclear@0: {
nuclear@0: 	int c;
nuclear@0: 
nuclear@0: 	if((c = palm_color_index(r, g, b)) == -1) {
nuclear@0: 		return -1;
nuclear@0: 	}
nuclear@0: 	return base_index[c];
nuclear@0: }
nuclear@0: 
nuclear@0: int palm_color_range(void)
nuclear@0: {
nuclear@0: 	return range;
nuclear@0: }