vpGetLight - get lighting properties
#include <volpack.h>
vpResult
vpGetLight(vpc, light_num, property, n0_ptr, n1_ptr,
    n2_ptr)
  -  
 
  - vpContext *vpc;
 
  -  
 
  - int light_num;
 
  -  
 
  - int property;
 
  -  
 
  - double *n0_ptr, *n1_ptr, *n2_ptr;
 
  - vpc
 
  - VolPack context from vpCreateContext.
 
  - light_num
 
  - A constant specifying a particular light source (VP_LIGHT0, VP_LIGHT1,
      ..., VP_LIGHT5).
 
  - property
 
  - A constant specifying one lighting property (VP_COLOR or
    VP_DIRECTION).
 
  - n0_ptr, n1_ptr,
    n2_ptr
 
  - Locations for storing the result: components of an RGB color (for
      VP_COLOR) or a direction vector (for VP_DIRECTION).
 
vpGetLight is used to get the properties of a light source.
    The arguments are exactly analogous to vpSetLight except that the
    final three arguments are pointers to locations for storing the lighting
    properties.
The normal return value is VP_OK. The following error return
    values are possible:
  - VPERROR_LIMIT_EXCEEDED
 
  - The light number is invalid or exceeds an implementation limit.
 
  - VPERROR_BAD_OPTION
 
  - The property argument is invalid.
 
VolPack(3), vpCreateContext(3), vpSetLight(3)