surface
st_pattern_lambert_texture(float	Kd = 1, /* fake brightness */
					wave_move = 4, /* [0 10] */
					wave_freq = 3, /* [0 10]*/
					wave_amp = 0.2, /* [0.1 0.5 0.005] */
					circ_size = 0.01,
					arch_cont = 0.4, /* [0.0 1.0 0.1] */
					arch1_ignore = 0, /* [0 or 1] */
					arch2_ignore = 0, /* [0 or 1] */
					arch3_ignore = 0, /* [0 or 1] */
					cres_ignore = 0, /* [0 or 1] */
					circ_ignore = 0, /* [0 or 1] */
					squar_ignore = 0, /* [0 or 1] */
					squar_size = 0, /* [0 0.7 0.05] */
					bar1_move = 0, /* [-0.2 0.4 0.1] */
					bar2_move = 0, /* [-0.2 0.6 0.1] */
					bar3_move = 0, /* [-0.2 1 0.1] */
					bar4_move = 0, /* [-0.2 1.2 0.1] */
					bar5_move = 0, /* [-0.2 1.8 0.1] */
					bar6_move = 0, /* [-0.2 2 0.1] */
					wav_tp_mov = 0, /* [-1 1 0.2] */
					wav_bm_mov = 0, /* [-1 1 0.2] */
					tex_opac = 0.5;
		   string	tex_name = "bnw_grid.tex";
		   color	arch = color (1,0.8,0),
					background = color (0.1, 0.2, 0.7))
{
	normal n = normalize(N);
	normal nf = faceforward(n, I);
	color surfcolor = background;
	color orng = color (0.8,sin(s),0);
	color blu2 = color (0,0,cos(t));
	color diffuseColor = diffuse(nf) * Kd;
	
	// middle - bars
	if ((s + t - 0.8 - bar1_move) < 1 && (s + t - 0.6 - bar1_move) > 1)
		surfcolor = color (sin(s),0,0.2);
	if ((s + t - 0.6 - bar2_move) < 1 && (s + t - 0.4 - bar2_move) > 1)
		surfcolor = color (0.8,sin(t),0);
	
	if ((s + t - 0.2 - bar3_move) < 1 && (s + t + 0 - bar3_move) > 1)
		surfcolor = color (sin(s),0,0.2);
	if ((s + t + 0.2 - bar4_move) > 1 && (s + t + 0 - bar4_move) < 1)
		surfcolor = color (0.8,sin(t),0);
	
	if ((s + t + 0.8 - bar5_move) > 1 && (s + t + 0.6 - bar5_move) < 1)
		surfcolor = color (sin(s),0,0.2);
	if ((s + t + 1 - bar6_move) > 1 && (s + t + 0.8 - bar6_move) < 1)
		surfcolor = color (0.8,sin(t),0);

	// top left - cresent/ellipse
	if ((t+0.1)*(t+0.1)+(s+0.1)*(s-(0.2 + arch_cont)) < 0.15 &&
		(t+0.1)*(t+0.1)+(s+0.1)*(s-(0.2 + arch_cont)) > 0.08)
		if(cres_ignore == 0)
			surfcolor = arch;
	
	// middle - wavy diagonal
	float wavy = sin(s * 2 * PI * wave_freq);
	wavy = ((wavy + wave_move) * 0.5);
	wavy = wavy * wave_amp;
	
	if (t + s < wavy + wav_tp_mov)
		surfcolor = orng;
	if (t - s > wavy + wav_bm_mov)
		surfcolor = orng;
	
	// top rigfht - arches
	if ((sqrt(s * s) - pow((t * t),1)) > .7)
		if (arch1_ignore == 0)
			surfcolor = color (0.7,0.2,0);	
	if ((sqrt(s * s) - pow((t * t),1)) > .8)
		if (arch2_ignore == 0)
			surfcolor = color (0,0.2,0.6);
	if ((sqrt(s * s) - pow((t * t),1)) > .9)
		if (arch3_ignore == 0)
			surfcolor = color (0.6,0.2,0);
	
	// bottom left - square
	if (t >= (0.7 - squar_size) && s <= (0.3 + squar_size))
		if (squar_ignore == 0)
			surfcolor = blu2;
	
	// bottom left - circle on square
	if ((t-0.85)*(t-0.85)+(s-0.15)*(s-0.15) < circ_size)
		if (circ_ignore == 0)
			surfcolor = color (0.8,cos(t),0);
	
	color texMp = color texture (tex_name, 1*t, (0.4*s + 0.8));
	surfcolor = surfcolor - (texMp * tex_opac);
	
	Ci = Oi * Cs * surfcolor * diffuseColor;
}