c4d.utils.GeRayCollider

class c4d.utils.GeRayCollider

Evaluates intersections between a ray and a polygon object. The ray is defined by a point, a ray and length.

In the following example a ray intersects a cube:

Methods Signatures

GeRayCollider.__init__()

GeRayCollider.Init()	Initializes the ray collider with the object specified by goal.
GeRayCollider.Intersect()	Checks if the line segment specified by ray_p to ray_p + ray_dir*ray_length intersects the object.
GeRayCollider.GetIntersectionCount()	Returns the number of intersections found by Intersect().
GeRayCollider.GetIntersection()	Retrieves the intersection information, found by GeRayCollider.Intersect(), by index:
GeRayCollider.GetNearestIntersection()	Retrieves the intersection, found by Intersect(), closest to the start of the ray.

Methods Documentation

GeRayCollider.__init__(self)

GeRayCollider.Init(self, goal, force=False)

Initializes the ray collider with the object specified by goal.

Parameters

• goal (c4d.PolygonObject) – The object to check for intersections. The object is copied.

• force (bool) –

  If False then Cinema checks if the passed object’s C4DAtom.GetDirty(c4d.DIRTYFLAGS_DATA) is unchanged. If yes, it does nothing and returns True.

  If True it always rebuilds the cache.

Return type

bool

Returns

True if successful, otherwise False.

GeRayCollider.Intersect(self, ray_p, ray_dir, length, only_test=False)

Checks if the line segment specified by ray_p to ray_p + ray_dir*ray_length intersects the object.

Parameters

• ray_p (c4d.Vector) – Start point of the ray in object coordinates

• ray_dir (c4d.Vector) – Ray direction in object coordinates.

• ray_length (number) – Ray length.

• only_test (bool) – If this is True no information about the intersections are stored, so only the return value can be used to tell if there were intersections or not.

Return type

bool

Returns

True if there was in intersection, otherwise False

GeRayCollider.GetIntersectionCount(self)

Returns the number of intersections found by Intersect().

Return type

int

Returns

Number of intersections.

GeRayCollider.GetIntersection(self, number)

Retrieves the intersection information, found by GeRayCollider.Intersect(), by index:

import c4d

rc = c4d.utils.GeRayCollider()

intersection = rc.GetIntersection(id)

intersection["face_id"]  # The polygon index, int
intersection["tri_face_id"]  # If first half of quad or triangle face_id + 1, else -(face_id + 1), int
intersection["hitpos"]  # Position of the intersection, c4d.Vector
intersection["distance"]  # Distance to the intersection, float
intersection["s_normal"]  # Same as f_normal (reserved for phong normal at the intersection (Not normalized)), c4d.Vector
intersection["f_normal"]  # Face normal (Not normalized), c4d.Vector
intersection["barrycoords"]  # Barycentric coordinates of the intersection (x = u, y = v, z = d), c4d.Vector
intersection["backface"]  # True if the intersected face's normal points away from the camera, otherwise False, bool

Parameters

number (int) – Intersection index.

Raises

IndexError – If intersection index is out of range : 0<=number<GetIntersectionCount().

Return type

dict

Returns

The intersection information.

GeRayCollider.GetNearestIntersection(self)

Retrieves the intersection, found by Intersect(), closest to the start of the ray.

Return type

Optional[Dict[int, int, c4d.Vector, float, c4d.Vector, c4d.Vector, c4d.Vector, bool]]

Returns

The nearest intersection or None if there was no intersection.