##RenderMan RIB-Structure 1.0
version 3.03

###########################################################################
#
# This RIB file give a demonstration of the use of automatic shadows
# which can be attenuated by opacity of individual objects.
#
# Casting shadows:
#    By default, light sources do not cast shadows.  The following RIB
#    sets a nonstandard attribute which causes any subsequently declared
#    light sources to automatically cast shadows using ray tracing:
#              Declare "shadows" "string"
#              Attribute "light" "shadows" "on"
#              LightSource ....
#    This attribute "affixes" itself to the lightsource when it's
#    declared.  Note that it can be pushed and popped by AttributeBegin/End,
#    just like any other attribute.
#
# Occluder options:
#    When a light source casts shadows, by default the object casts a
#    shadow which blocks out light according to the Opacity in effect
#    when the object was declared.  For some complex objects (like the
#    ones in this scene), the surface shader needs to be evaluated before
#    the renderer can know exactly what the opacity needs to be.  This
#    is slower than the default, and only needs to be done when the 
#    surface shader causes the opacity to change across the surface.  In
#    this case, the proper attribute to set is:
#           Declare "casts_shadows" "string"
#           Attribute "render" "casts_shadows" "shade"
#
# These attributes are all described in the "BMRT User Guide".
#
###########################################################################

#Option "searchpath" "shader" [".:../shaders:&"]
Display "assn2.tif" "file" "rgb" "compression" "none"
Format 640 480 -1
PixelSamples 2 2
Projection "perspective" "fov" 45
Translate 0 -2 8
Rotate -110 1 0 0


WorldBegin

LightSource "ambientlight" 1 "intensity" 0.5

LightSource "distantlight" 1 "from" [0 1 4] "to" [0 0 0] "intensity" 0.8

# Declare "brickwidth" float
# Declare "brickheight" float
# Declare "mortarthickness" float

AttributeBegin
  Color  [ 1.0 1.0 1.0  ] 
  Displacement "IDgloop" "magnitude" .15
  Polygon "P"  [  5 -5 0 5 5 0 -5 5 0 -5 -5 0] 
AttributeEnd

AttributeBegin
  Color  [ 1.0 1.0 1.0  ] 
  ShadingRate 0.5
  Displacement "IDgloop" "magnitude" .25
  Surface "IDhair"
  Polygon "P" [ -5 -5 5  5 -5 5  5 -5 0  -5 -5 0    ] 
AttributeEnd

AttributeBegin
  Translate 0 0 2
  Color [1 1 .06]
 # Surface "plastic"

  Displacement "IDbubbly" "Kd" [-.2]
  
  Sphere 1 -1 1 360
AttributeEnd

WorldEnd