def intersect(self, ray, intersection):
"""Compute an intersection."""
w2p = self.world_to_primitive.interpolate(ray.time)
ray_primitive = w2p(ray)
intersection = Intersection()
if not self.primitive.intersect(ray_primitive, intersection):
return False
ray.maxt = ray_primitive.maxt
intersection.primitive_id = self.primitive_id
if not w2p.is_identity():
# Compute world-to-object transformation for instance
intersection.world_to_object = intersection.world_to_object * w2p
intersection.object_to_world = inverse(
intersection.world_to_object)
p2w = inverse(w2p)
# Transform instance's differential geometry to world space
intersection.dg.p = p2w(intersection.dg.p)
intersection.dg.nn = normalize(p2w(intersection.dg.nn))
intersection.dg.dpdu = p2w(intersection.dg.dp_du)
intersection.dg.dpdv = p2w(intersection.dg.dp_dv)
intersection.dg.dndu = p2w(intersection.dg.dn_du)
intersection.dg.dndv = p2w(intersection.dg.dn_dv)
return True
def __init__(self, camera_to_world, projection, screen_window, s_open,
s_close, lens_radius, focal_distance, film):
"""Default constructor for ProjectiveCamera."""
super(ProjectiveCamera, self).__init__(camera_to_world, s_open,
s_close, film)
# initialize depth of field parameters
self.lens_radius = lens_radius
self.focal_distance = focal_distance
# compute projective camera transformations
self.camera_to_screen = projection
# compute projective camera screen transformations
sc1 = scale(float(film.x_resolution), float(film.y_resolution), 1.0)
sc2 = scale(1.0 / (screen_window[1] - screen_window[0]),
1.0 / (screen_window[2] - screen_window[3]), 1.0)
tr = translate(Point(-screen_window[0], -screen_window[3], 0.0))
self.screen_to_raster = sc1 * sc2 * tr
self.raster_to_screen = inverse(self.screen_to_raster)
self.raster_to_camera = inverse(self.camera_to_screen) * \
self.raster_to_screen
def __init__(self, camera_to_world, projection, screen_window,
s_open, s_close, lens_radius, focal_distance,
film):
"""Default constructor for ProjectiveCamera."""
super(ProjectiveCamera, self).__init__(camera_to_world,
s_open, s_close,
film)
# initialize depth of field parameters
self.lens_radius = lens_radius
self.focal_distance = focal_distance
# compute projective camera transformations
self.camera_to_screen = projection
# compute projective camera screen transformations
sc1 = scale(float(film.x_resolution), float(film.y_resolution), 1.0)
sc2 = scale(1.0 / (screen_window[1] - screen_window[0]),
1.0 / (screen_window[2] - screen_window[3]),
1.0)
tr = translate(Point(-screen_window[0], -screen_window[3], 0.0))
self.screen_to_raster = sc1 * sc2 * tr
self.raster_to_screen = inverse(self.screen_to_raster)
self.raster_to_camera = inverse(self.camera_to_screen) * \
self.raster_to_screen
def intersect(self, ray, intersection):
"""Compute an intersection."""
w2p = self.world_to_primitive.interpolate(ray.time)
ray_primitive = w2p(ray)
intersection = Intersection()
if not self.primitive.intersect(ray_primitive, intersection):
return False
ray.maxt = ray_primitive.maxt
intersection.primitive_id = self.primitive_id
if not w2p.is_identity():
# Compute world-to-object transformation for instance
intersection.world_to_object = intersection.world_to_object * w2p
intersection.object_to_world = inverse(intersection.world_to_object)
p2w = inverse(w2p)
# Transform instance's differential geometry to world space
intersection.dg.p = p2w(intersection.dg.p)
intersection.dg.nn = normalize(p2w(intersection.dg.nn))
intersection.dg.dpdu = p2w(intersection.dg.dp_du)
intersection.dg.dpdv = p2w(intersection.dg.dp_dv)
intersection.dg.dndu = p2w(intersection.dg.dn_du)
intersection.dg.dndv = p2w(intersection.dg.dn_dv)
return True
