.PS
define smiley {
	# takes three arguments: x, y and size (radius)

	r0 = $3			# Face
	r1 = 0.4*r0		# Radius of mouth and eye locations
	r2 = 0.04*r0	# Radius of eyes

C: circle rad r0 at ( $1, $2 )

	circle rad r2 filled at last circle + ( r1, r1 )		# Right eye
	circle rad r2 filled at 2nd last circle + ( -r1, r1 )	# Left eye

	pi = atan2( 0, -1 )
S: C + ( r1 * cos(1.25*pi), r1 * sin(1.25*pi) )
	line from S to S
	for phi=1.25*pi to 1.75*pi by 0.1 do {
		line to C + ( r1 * cos(phi), r1 * sin(phi) )		# Mouth
	}
}

pi2 = 2 * atan2( 0, -1 )
for x=0.1 to 1.3 by 0.08 do {
	smiley( 1.5 * x * cos(x*pi2), 1.1 * x * sin(x*pi2), 0.23 * x )
}
.PE