/*
 * CS5600 University of Utah
 * Charles McGarvey
 * mcgarvey@eng.utah.edu
 */

#ifndef _RAY_HH_
#define _RAY_HH_

#include "vec.hh"


/*
 * A simple ray class.
 */
struct ray
{
    vec_t o;
    vec_t d;
};
typedef struct ray ray_t;

/*
 * Initialize a ray with an origin point and a direction.
 */
INLINE_MAYBE
void ray_init(ray_t* r, vec_t origin, vec_t direction)
{
    r->o = origin;
    r->d = direction;
}


/*
 * Create a new ray with an origin point and a direction.
 */
INLINE_MAYBE
ray_t ray_new(vec_t origin, vec_t direction)
{
    ray_t r;
    ray_init(&r, origin, direction);
    return r;
}


/*
 * Normalize the direction of a ray.
 */
INLINE_MAYBE
ray_t ray_normalize(ray_t r)
{
    return ray_new(r.o, vec_normalize(r.d));
}


/*
 * Solve for a point along the array, given a distance.  The ray must be
 * normalized for this to work as expected.
 */
INLINE_MAYBE
vec_t ray_solve(ray_t r, scal_t distance)
{
    return vec_add(r.o, vec_scale(r.d, distance));
}


#endif // _RAY_HH_