ff-chess.c

#if 0
gcc -s -O2 -o ~/bin/ff-chess ff-chess.c
exit
#endif

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

static unsigned int xsize,ysize,tsize,x,y,xx,yy;
static unsigned char color[16];

static void
usage(void)
{
	fprintf(stderr,
		"Usage: ff-chess <columns> <rows> <tile size> <colour> <colour>                \n"
		"                                                                              \n"
		"Creates an empty chess board of arbitrary size.                               \n"
		"                                                                              \n"
		"ff-chess does not read any data from stdin.                                   \n"
		"                                                                              \n"
		"The program takes five arguments:                                             \n"
		"   - the number of columns (files)                                            \n"
		"   - the number of rows (ranks)                                               \n"
		"   - tile size (in pixels)                                                    \n"
		"   - first tile colour                                                        \n"
		"   - second tile colour                                                       \n"
		"                                                                              \n"
		"The colours can have the following patterns:                                  \n"
		"   rrggbb            three pairs of 8-bit hex values                          \n"
		"   rrggbbaa          four pairs of 8-bit hex values                           \n"
		"   rrrrggggbbbb      three pairs of 16-bit hex values                         \n"
		"   rrrrggggbbbbaaaa  four pairs of 16-bit hex values                          \n"
		"                                                                              \n"
		"A normal chess board has 8 files and 8 ranks, and the first tile colour will  \n"
		"be white (or a light colour).                                                 \n"
		"                                                                              \n"
		"It is possible to use ff-composite and ff-text (together with sed) in order to\n"
		"draw the pieces on a chess board, see the example below.                      \n"
		"                                                                              \n"
		"Example usage:                                                                \n"
		"   $ ff-chess 8 8 64 DDDDDD 222222 > chess.ff                                 \n"
		"   $ ff-chess 8 8 32 E5E5D7 001000 \\                                         \n"
		"     | ff-composite <(pngff < pieces.png \\                                   \n"
		"     | ff-text +PNBRQKpnbrqk 32 32 `sed 's.7.43.g;s.6.33.g;s.5.32.g;s.4.22.g;s.3.21.g;s.2.11.g;s./. .g' < board.fen`) 0,0,0 \\\n"
		"     | ff-border 0020FF 8 > chess.ff                                          \n"
		"\n"
	);
	exit(1);
}

static void parse_color(unsigned char*out,const char*in) {
	switch(strlen(in)) {
		case 6:
			sscanf(in,"%02hhX%02hhX%02hhX",out+0,out+2,out+4);
			out[1]=out[0];
			out[3]=out[2];
			out[5]=out[4];
			out[6]=out[7]=255;
			break;
		case 8:
			sscanf(in,"%02hhX%02hhX%02hhX%02hhX",out+0,out+2,out+4,out+6);
			out[1]=out[0];
			out[3]=out[2];
			out[5]=out[4];
			out[7]=out[6];
			break;
		case 12:
			sscanf(in,"%02hhX%02hhX%02hhX%02hhX%02hhX%02hhX",out+0,out+1,out+2,out+3,out+4,out+5);
			out[6]=out[7]=255;
			break;
		case 16:
			sscanf(in,"%02hhX%02hhX%02hhX%02hhX%02hhX%02hhX%02hhX%02hhX",out+0,out+1,out+2,out+3,out+4,out+5,out+6,out+7);
			break;
		default:
			fprintf(stderr,"Invalid color format (%d)\n",(int)strlen(in));
			exit(1);
	}
}

int main(int argc,char**argv) {
	if (argc>1 && (!strcmp(argv[1],"-h") || !strcmp(argv[1],"--help"))) {
		usage();
	}
	if(argc!=6) {
		fprintf(stderr,"Too %s arguments\n",argc<6?"few":"many");
		return 1;
	}
	xsize=strtol(argv[1],0,0);
	ysize=strtol(argv[2],0,0);
	tsize=strtol(argv[3],0,0);
	parse_color(color,argv[4]);
	parse_color(color+8,argv[5]);
	fwrite("farbfeld",1,8,stdout);
	putchar((xsize*tsize)>>24);
	putchar((xsize*tsize)>>16);
	putchar((xsize*tsize)>>8);
	putchar((xsize*tsize)>>0);
	putchar((ysize*tsize)>>24);
	putchar((ysize*tsize)>>16);
	putchar((ysize*tsize)>>8);
	putchar((ysize*tsize)>>0);
	for(y=0;y<ysize;y++) for(yy=0;yy<tsize;yy++) for(x=0;x<xsize;x++) for(xx=0;xx<tsize;xx++) fwrite(color+(((x+y)&1)<<3),1,8,stdout);
	return 0;
}