Category : Printer + Display Graphics
Archive   : PLYDAT.ZIP
Filename : SINSURF.PI

# the value theta_offset is used in animations to make
# the surface move
define theta_offset radians(frame * 12)

# Set up the camera
viewpoint {
from <0,5,-5>
at <0,0,0>
up <0,1,0>
angle 30
resolution 160, 160
}

define white <1,1,1>
define DarkSlateGray <0.184314, 0.309804, 0.309804>
define red <1, 0, 0>
define SkyBlue <0.196078, 0.6, 0.8>

# Set up background color & lights
background SkyBlue
light <10,10,-10>

# Define the color of the sphere
define glossy_red
texture {
surface {
ambient red, 0.2
diffuse red, 0.7
specular white, 0.4
}
}

define two_sphere
object { sphere <0,0,0>, 2 }

# Define a sinusoidal surface
object {
function y - 0.25 * sin(18.85 * x * z + theta_offset)
glossy_red
bounds two_sphere
}