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Action:
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Gets the normal of a surface at the specified parameter values.
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Filename:
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kern/kern_scm/surf_scm.cxx
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Syntax:
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(surface:eval-normal surf u v)
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Arg Types:
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surf
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surface
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u
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real
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v
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real
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Returns:
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gvector
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surf specifies a surface.
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u specifies a
u parameter value.
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v specifies a
v parameter value.
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Example:
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; surface:eval-normal
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; Create a solid block.
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(define block1
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(solid:block (position 0 0 0)
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(position 40 40 40)))
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;; block1
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; Get a list of the faces of the solid block.
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(define entities1
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(entity:faces block1))
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;; entities1
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; Convert one face to a surface.
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(define surface1 (surface:from-face
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(car entities1)))
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;; surface1
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; Evaluate the normal of the surface with the
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; specified parameter values.
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(surface:eval-normal surface1 1 1)
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;; #[gvector 0 0 1]
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