lst = nil();
for ( i = 1, 1, 10,
    for ( j = 1, 1, 10,
	pl = poly( list( point( i, j, 0 ),
		         point( i + 1, j, 0 ),
			 point( i + 1, j + 1, 0 ),
			 point( i, j + 1, 0 ) ),
		   off ):
	if ( 2 * floor((i + j) / 2) == i + j,
	     attrib( pl, "rgb", "255,255,255" ),
	     attrib( pl, "rgb", "100,100,100" ) ):
	lst = lst + list( pl * sc( 1 ) ) ) );
viewclear();
viewobj( lst );

save( "ir_chckr", lst );

free( pl );
free( lst );

exit();