Inode *cylin_intersect(Prim *p, Ray ro)
{
double a, b, c, disc, t0, t1, t2, t3;
Inode *i0, *i1;
int flag[4] = {FALSE, FALSE, FALSE, FALSE};
Ray r = ray_transform(ro, p->ti);
Vector3 Sol0, Sol1, Sol2, Sol3;
a = SQR(r.d.x) + SQR(r.d.y);
b = 2 * (r.o.x * r.d.x + r.o.y * r.d.y);
c = SQR(r.o.x) + SQR(r.o.y) - 1;
// Case 0: no solution / infinite solutions
if ((disc = SQR(b) - 4 * a * c) <= 0)
return (Inode *)0;
if ( fabs(a) < RAY_EPS ) {
return (Inode *)0;
} else {
t0 = (-b - sqrt(disc)) / (2 * a);
t1 = (-b + sqrt(disc)) / (2 * a);
Sol0 = ray_point(r, t0);
Sol1 = ray_point(r, t1);
if (t1 > RAY_EPS && Sol1.z >= 0 && Sol1.z <= 1){
flag[1] = TRUE;
}
if (t0 > RAY_EPS && Sol0.z >= 0 && Sol0.z <= 1){
flag[0] = TRUE;
}
}
// Ray NOT parallel to base caps --> Cap intersections
if ( fabs(r.d.z) > RAY_EPS ){
t2 = - (r.o.z) / (r.d.z);
t3 = (1 - (r.o.z)) / (r.d.z);
Sol2 = ray_point(r,t2);
Sol3 = ray_point(r,t3);
if (t2 > RAY_EPS && (SQR(Sol2.x) + SQR(Sol2.y)) <= 1)
flag[2] = TRUE;
if (t3 > RAY_EPS && (SQR(Sol3.x) + SQR(Sol3.y)) <= 1)
flag[3] = TRUE;
}
int k = 0, nsols = 0;
double t[4] = {t0, t1, t2, t3};
while (k < 4 && nsols < 2){
if (flag[k]){
Vector3 n = v3_unit(cylin_gradient(p, ray_point(ro, t[k])));
if ( nsols == 0 ){
i0 = inode_alloc(t[k], n, TRUE);
} else {
i1 = inode_alloc(t[k], n, FALSE);
i0->next = i1;
}
nsols++;
}
k++;
}
return i0;
}
Inode *torus_intersect(Prim *p, Ray ro)
{
double a, b, c, disc, t0, t1;
Inode *i0, *i1;
Ray r = ray_transform(ro, p->ti);
a = v3_sqrnorm(r.d);
b = 2 * v3_dot(r.d, r.o);
c = v3_sqrnorm(r.o) - 1;
if ((disc = SQR(b) - 4 * a * c) <= 0)
return (Inode *)0;
t0 = (-b - sqrt(disc)) / (2 * a);
t1 = (-b + sqrt(disc)) / (2 * a);
if (t1 < RAY_EPS)
return (Inode *)0;
if (t0 < RAY_EPS) {
Vector3 n1 = v3_unit(torus_gradient(p, ray_point(r, t1)));
return inode_alloc(t1, n1, FALSE);
} else {
Vector3 n0 = v3_unit(torus_gradient(p, ray_point(ro, t0)));
Vector3 n1 = v3_unit(torus_gradient(p, ray_point(ro, t1)));
i0 = inode_alloc(t0, n0, TRUE);
i1 = inode_alloc(t1, n1, FALSE);
i0->next = i1;
return i0;
}
}
main(int argc, char **argv)
{
Prim *o;
Color c; int u, v;
Ray r; Inode *l;
o = sphere_instance(&sphere_funcs);
init_sdl();
s = scene_read();
init_render();
for (v = s->view->sc.ll.y; v < s->view->sc.ur.y; v += 1) {
for (u = s->view->sc.ll.x; u < s->view->sc.ur.x; u += 1) {
r = ray_unit(ray_transform(ray_view(u, v), mclip));
if ((l = ray_intersect(s->objs, r)) != NULL)
c = point_tshade(ray_point(r, l->t), l->n, s->view->center, rc, l->m, o);
else
c = bgcolor;
inode_free(l);
img_putc(s->img, u, v, col_dpymap(c));
}
}
img_write(s->img,"stdout",0);
exit(0);
}
/**
* Calculate the intersection of an object and a ray with
* distance within the given bounds.
* First triest to find out if the ray intersects the bounding box.
* \note The diffrence between this function and the virtual method
* object::get_intersection is that this method works in the world
* coordinates.
*/
float object_ray_intersection(struct object *o, const struct ray *r,
float lowerBound, float upperBound){
if(!bounding_box_ray_intersection(
&(o->boundingBox), r, lowerBound, upperBound)){
return NAN;
}
struct ray transformed;
float ratio = ray_transform(r, &(o->invTransform), &transformed);
lowerBound *= ratio;
upperBound *= ratio;
return (o->get_intersection(o, &transformed, lowerBound, upperBound)) / ratio;
}
main(int argc, char **argv)
{
Color c;
int u, v;
Ray r;
init_sdl();
s = scene_read();
init_render();
for (v = s->view->sc.ll.y; v < s->view->sc.ur.y; v += 1) {
for (u = s->view->sc.ll.x; u < s->view->sc.ur.x; u += 1) {
r = ray_unit(ray_transform(ray_view(u, v), mclip));
c = ray_shade(0, 1., r, rc, s->objs);
img_putc(s->img, u, v, col_dpymap(c));
}
}
img_write(s->img,"stdout",0);
exit(0);
}
bool CEntityMiscModel::TestRay( const ray_t *ray, vec_t *dist ) const {
vec_t dist_start = *dist;
vec_t dist_local = *dist;
ray_t ray_local = *ray;
if ( aabb_test_ray( &m_BBox, ray ) == 0 ) {
return false;
}
ray_transform( &ray_local, m_inverse_transform );
if ( m_model && m_model->pSelect ) {
if ( m_model->pSelect->TestRay( &ray_local, &dist_local ) ) {
*dist = dist_local;
}
}
else{ *dist = dist_local; }
return *dist < dist_start;
}
