int hitRing(entity_t * ent, point_t base, vector_t dir, hitinfo_t * hit) {
if(hitPlane(ent, base, dir, hit) != 1) return 0;
assert(ent->magic == ENTITY_T);
sobj_t *sobj = ent->entDerived;
assert(sobj->magic == SCENEOBJ_T);
plane_t *plane = sobj->sobjDerived;
assert(plane->magic == PLANE_T);
ring_t * ring = plane->planeDerived;
assert(ring->magic == RING_T);
tuple_t r_centerTOhit = ray(plane->point, hit->hitpoint);
double d_hitpoint = length(r_centerTOhit);
double d_inner = length(scale(unitize(r_centerTOhit), ring->radius1));
double d_outer = length(scale(unitize(r_centerTOhit), ring->radius2));
return ((d_hitpoint > d_inner) && (d_hitpoint < d_outer));
}
void hitObjects(Point3D_t rayO, Vector3D_t rayD,ShadeRec_t* sr)
{
int i;
FLOAT_T t;
Normal_t normal;
Point3D_t localHitPoint;
FLOAT_T tmin = kHugeValue;
for(i = 0; i < nObjects; i++)
{
switch(objects[i]->type)
{
case SPHERE:
if(hitSphere(rayO,rayD,&t,sr,objects[i]->center,objects[i]->radius) && (t < tmin))
{
sr->hitAnObject = 1;
tmin = t;
sr->material = objects[i]->material;
//sr.local_hit_point = ray.o + t * ray.d;
sr->hitPoint.x = rayO.x + (t*rayD.x);
sr->hitPoint.y = rayO.y + (t*rayD.y);
sr->hitPoint.z = rayO.z + (t*rayD.z);
normal.x = sr->normal.x;
normal.y = sr->normal.y;
normal.z = sr->normal.z;
localHitPoint.x = sr->localHitPoint.x;
localHitPoint.y = sr->localHitPoint.y;
localHitPoint.z = sr->localHitPoint.z;
}
break;
case PLANE:
if(hitPlane(rayO,rayD,&t,sr,objects[i]->a,objects[i]->n) && (t < tmin))
{
sr->hitAnObject = 1;
tmin = t;
sr->material = objects[i]->material;
//sr.local_hit_point = ray.o + t * ray.d;
sr->hitPoint.x = rayO.x + (t*rayD.x);
sr->hitPoint.y = rayO.y + (t*rayD.y);
sr->hitPoint.z = rayO.z + (t*rayD.z);
normal.x = sr->normal.x;
normal.y = sr->normal.y;
normal.z = sr->normal.z;
localHitPoint.x = sr->localHitPoint.x;
localHitPoint.y = sr->localHitPoint.y;
localHitPoint.z = sr->localHitPoint.z;
}
break;
}
}
if(sr->hitAnObject)
{
sr->t = tmin;
sr->normal.x = normal.x;
sr->normal.y = normal.y;
sr->normal.z = normal.z;
sr->localHitPoint.x = localHitPoint.x ;
sr->localHitPoint.y = localHitPoint.y ;
sr->localHitPoint.z = localHitPoint.z ;
}
}
