##RenderMan RIB

version 3.03

#

# Could anyone explain what is wrong with this cubic NURB?

# I am expecting the grid lines to be evenly spaced in U

# Note that I calculated closure of an open knot vector

# U0 U1 U2 U3

# as

# U2 U3 U0 U1 U2 U3 U0

# Note that I have tried

# U3 U2 U0 U1 U2 U3 U0

#

#

Display "NURB.1.pic" "framebuffer" "rgba"

PixelSamples 2 2

PixelFilter "sinc" 3 3

Sides 2

Format 500 400 1.066

Projection "perspective" "fov" [43.6164]

Clipping 0.1 32768

Scale -1 1 1

Rotate -5.71055 1 0 0

Rotate 180 0 1 0

Translate 0 -0.582937 -8.2702

WorldBegin

#

# Note that the shader for grid is:

# surface grid()

# {

# Oi = 0.5;

# Ci = Oi*texture("/usr/local/prman/prman/lib/textures/grid.tex", s, t);

# }

#

Surface "grid"

NuPatch 7 4 [0 .1 .2 .3 .4 .5 .6 .7 .8 .9 1] 0 1 4 4 [0 0 0 0 1 1 1 1] 0 1 "P"

[

#V one

0 -3 2 # U 2

2 -3 0 # U 3

0 -3 -2 # U 0

-2 -3 0 # U 1

0 -3 2 # U 2

2 -3 0 # U 3

0 -3 -2 # U 0

#V two

0 -2 2

2 -2 0

0 -2 -2

-2 -2 0

0 -2 2

2 -2 0

0 -2 -2

#V three

0 -1 2

2 -1 0

0 -1 -2

-2 -1 0

0 -1 2

2 -1 0

0 -1 -2

#V four

0 0 2

2 0 0

0 0 -2

-2 0 0

0 0 2

2 0 0

0 -0 -2

]

WorldEnd

--

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