Dogcows Code - chaz/rasterize/blob - ray.hh

   1
   2 /*
   3  * CS5600 University of Utah
   4  * Charles McGarvey
   5  * mcgarvey@eng.utah.edu
   6  */
   7
   8 #ifndef _RAY_HH_
   9 #define _RAY_HH_
  10
  11 #include "vec.hh"
  12
  13
  14 /*
  15  * A simple ray class.
  16  */
  17 struct ray
  18 {
  19     vec_t o;
  20     vec_t d;
  21 };
  22 typedef struct ray ray_t;
  23
  24 /*
  25  * Initialize a ray with an origin point and a direction.
  26  */
  27 INLINE_MAYBE
  28 void ray_init(ray_t* r, vec_t origin, vec_t direction)
  29 {
  30     r->o = origin;
  31     r->d = direction;
  32 }
  33
  34
  35 /*
  36  * Create a new ray with an origin point and a direction.
  37  */
  38 INLINE_MAYBE
  39 ray_t ray_new(vec_t origin, vec_t direction)
  40 {
  41     ray_t r;
  42     ray_init(&r, origin, direction);
  43     return r;
  44 }
  45
  46
  47 /*
  48  * Normalize the direction of a ray.
  49  */
  50 INLINE_MAYBE
  51 ray_t ray_normalize(ray_t r)
  52 {
  53     return ray_new(r.o, vec_normalize(r.d));
  54 }
  55
  56
  57 /*
  58  * Solve for a point along the array, given a distance.  The ray must be
  59  * normalized for this to work as expected.
  60  */
  61 INLINE_MAYBE
  62 vec_t ray_solve(ray_t r, scal_t distance)
  63 {
  64     return vec_add(r.o, vec_scale(r.d, distance));
  65 }
  66
  67
  68 #endif // _RAY_HH_
  69