Description Initializes index value such that a subsequent call to GetPreviousRay() retrieves ray data for the last live ray in the ray buffer. This provides an alternate method to using GetLastRay() although GetLastRay() is preferred due to it's ability to detect when the ray buffer is empty.
Syntax InitGetPreviousRay( id )
Parameters
id As Long (or Huge_) Returns index number required for initialization. After execution, this variable contains the index number after that of the last ray that in the buffer. E.g. if the last live ray is index = 15 then this function returns id = 16.
Example The example below shows using this command in an alternative approach to the standard ray buffer looping construction to loop backwards over the rays in the buffer.
Dim success As Boolean Dim i As Long Dim tRay as T_RAY
InitGetPreviousRay(i) While GetPreviousRay(i, ray)
Print i 'do something here
Wend
See Also
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