#version 3.7;
global_settings{ assumed_gamma 1.0 }

#include "colors.inc"

camera {
location 10*z+5*y+5*x
up image_height*y
right image_width*x
direction z
angle 16
look_at 0.5*y
}

sphere { 0, 0.1 texture { pigment { White } } } 
sphere { y, 0.1 texture { pigment { Green } } } 
cylinder { -2*y, 2*y, 0.01 texture{ pigment { Green } } }
sphere { z, 0.1 texture { pigment { Blue } } } 
cylinder { -2*z, 2*z, 0.01 texture{ pigment { Blue } } }
sphere { x, 0.1 texture { pigment { Red } } } 
cylinder { -2*x, 2*x, 0.01 texture{ pigment { Red } } }

light_source { <40,80,40>, 1 }

#declare SR=function{ spline{ 
	natural_spline
		0, <0,0,0>
		0.25, <0.25,0,0.1>
		0.30, <0.30,0,0>
		0.35, <0.35,0,-0.1>
		0.40, <0.40,0,0>
		0.45, <0.45,0,0.1>
		0.50, <0.50,0,0>
		0.55, <0.55,0,-0.1>
		0.60, <0.60,0,0>
		0.65, <0.65,0,0.1>
		0.70, <0.70,0,0>
		0.75, <0.75,0,-0.1>
		0.80, <0.80,0,0>
		1, <1,0,0>
		1, <1,0,0>
		2, <0,1,0>
		2.5, <0.5,0.75,0.5>
		3, <0,0,1>
		3.5, <-0.5,0,0.5>
		4, <0,0,0>
} }
parametric 
{
	function { SR(u).x }
	function { SR(u).y+v/5 }
	function { SR(u).z }
	<0,0>,<4,1>
		contained_by { sphere { 0, 2 } } 
	precompute 10 x,y,z
		texture { pigment{ Yellow } }
}