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Action:
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Gets the position on a curve closest to the pick-ray.
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Filename:
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kern/kern_scm/crv_scm.cxx
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Syntax:
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(curve:ray-pos [curve pick-ray] | [entray])
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Arg Types:
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curve
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curve
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pick-ray
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ray
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entray
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entray
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Returns:
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pair
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Errors:
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EDGE with no
CURVE
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Description:
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The gvector on the curve can determine which end of a curve has been picked. If
(< 0.5 (cdr (curve:ray-pos pick))), the curve is picked near the start position; otherwise, it is picked near the end position. This extension returns a
pair-pair, where the first element is the position on the curve closest to the input ray. The second element is the corresponding parameter of the position in the range 0 to 1.
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curve specifies the curve.
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pick-ray specifies the ray. The ray is a position on the curve and a gvector closest to the pick.
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entray specifies the curve and the ray.
entray could be used in place of
curve and
pick-ray.
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Example:
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; curve:ray-pos
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; Create a spline edge.
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(define edge1
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(edge:spline (list (position 0 0 0)
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(position 0 -30 0) (position -30 18 0)) 0 45))
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;; edge1
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; Determine the position on the edge that
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; is closest to the specified position.
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(curve:ray-pos (entray edge1
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(ray (position 0 -30 0) (gvector 0 0 1))))
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;; (#[position 8.88178419700125e-16 -30 0] .
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;; 0.346404775941922)
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