void ray_def::regress(const coord_def &point)

void ray_def::regress()

    advance(true, &point);

    advance(false);

    void regress(const coord_def &point);

    void regress();

 * called from: fight - monstuff - spells - spells1 - spells2
 * *********************************************************************** */
#if 0
void delete_cloud( int cloud );
void new_cloud( int cloud, int type, int x, int y, int decay );
void place_cloud(unsigned char cl_type, unsigned char ctarget_x, unsigned char ctarget_y, unsigned char cl_range);
#endif
/* ***********************************************************************

                    ray.regress(pbolt.target());

                    do
                        ray.regress();
                    while (grid_is_solid(grd(ray.pos())));

                    ray.regress(pbolt.target());

                    do
                        ray.regress();
                    while (grid_is_solid(grd(ray.pos())));