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Description:
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A
ray is a composite data type, consisting of a position and a gvector. Rays represent pick direction vectors, infinite lines, or planes.
ray objects are not saved as part of the model.
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The direction represents a displacement vector in 3D Cartesian space. Internally, a direction is represented in model space coordinates. When coordinates are required, the coordinates are entered relative to the active coordinate system.
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Derivation:
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ray : position : gvector : scheme-object
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C++ Type:
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pick_ray
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External Rep:
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#[ray (%g %g %g) (%g %g %g)]
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where the first triplet of doubles is the (x y z) position, and the second triplet of doubles is the (x y z) gvector.
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Example:
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; ray (data type)
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; Define and inquire a ray object.
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(define x-ray (ray (position 0 0 0) (gvector 1 0 0)))
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;; x-ray
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(ray? x-ray)
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;; #t
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