# File benchmark/bm_ao_render.rb, line 90
def intersect(ray, isect)
rs = ray.org.vsub(@center)
b = rs.vdot(ray.dir)
c = rs.vdot(rs) - (@radius * @radius)
d = b * b - c
if d > 0.0
t = - b - Math.sqrt(d)
if t > 0.0 and t < isect.t
isect.t = t
isect.hit = true
isect.pl = Vec.new(ray.org.x + ray.dir.x * t,
ray.org.y + ray.dir.y * t,
ray.org.z + ray.dir.z * t)
n = isect.pl.vsub(@center)
isect.n = n.vnormalize
end
end
end