Description Retrieves the direction vector for a specified ray. Depending on the number of rays traced, it may be necessary to dimension ray index and ray counter variables as data type Huge_ instead of Long. Please see Multi-threaded Raytracing for more information.
Syntax GetRayDirection id, a, b, c
Parameters id As Long (or Huge_) Identifier for the ray.
a As Double The X component of the direction vector.
b As Double The Y component of the direction vector.
c As Double The Z component of the direction vector.
Remarks This subroutine retrieves the direction vector for a specified ray. If there is a problem, the subroutine toggles an error and does not modify a, b, or c.
Ray data is in global corrdiunates. convert to local coordinates using TransformDirection.
See Also Examples
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