/** Intersects this ray with a sphere. */
public Collection<Vec3f> intersect(Sphere sphere) {
float[] t = Line.intersectLengths(p, d, sphere);
if (t == null) return null;
ArrayList<Vec3f> intersections = new ArrayList<Vec3f>(2);
for (float time : t) if (time >= 0) intersections.add(p.plus(d.times(time)));
return intersections;
}
/** Intersects this ray with a convex polygon. */
public Vec3f intersect(ConvexPolygon poly) {
float nDotD = poly.n.dot(d);
if (nDotD == 0) return null;
float t = poly.n.dot(poly.v[0].minus(p)) / nDotD;
Vec3f x = p.plus(d.times(t));
return (poly.contains(x) ? x : null);
// Vec3f x = intersect(new Plane(poly.v[0], poly.n));
// return (x != null || poly.contains(x)) ? x : null;
}
/** Intersects this ray with a plane. */
public Vec3f intersect(Plane plane) {
float t = Line.intersectLength(p, d, plane);
return t < 0 ? null : p.plus(d.times(t));
}