# CollisionTraverser¶

from panda3d.core import CollisionTraverser

class CollisionTraverser

Bases: Namable

This class manages the traversal through the scene graph to detect collisions. It holds ownership of a number of collider objects, each of which is a CollisionNode and an associated CollisionHandler.

When traverse() is called, it begins at the indicated root and detects all collisions with any of its collider objects against nodes at or below the indicated root, calling the appropriate CollisionHandler for each detected collision.

Inheritance diagram

__init__(param0: CollisionTraverser)
__init__(name: str)
addCollider(collider: NodePath, handler: CollisionHandler)None

Adds a new CollisionNode, representing an object that will be tested for collisions into other objects, along with the handler that will serve each detected collision. Each CollisionNode may be served by only one handler at a time, but a given handler may serve many CollisionNodes.

The handler that serves a particular node may be changed from time to time by calling addCollider() again on the same node.

clearColliders()None

Completely empties the set of collision nodes and their associated handlers.

clearRecorder()None

Removes the CollisionRecorder from the traverser and restores normal low- overhead operation.

property colliders → Sequence[NodePath]

Returns the nth CollisionNode that has been added to the traverser via addCollider().

static getClassType()TypeHandle
getCollider(n: int)NodePath

Returns the nth CollisionNode that has been added to the traverser via addCollider().

getColliders()list
getHandler(collider: NodePath)CollisionHandler

Returns the handler that is currently assigned to serve the indicated collision node, or NULL if the node is not on the traverser’s set of active nodes.

getNumColliders()int

Returns the number of CollisionNodes that have been added to the traverser via addCollider().

getRecorder()CollisionRecorder

Returns the CollisionRecorder currently assigned, or NULL if no recorder is assigned.

getRespectPrevTransform()bool

Returns the flag that indicates whether the prev_transform stored on a node is respected to calculate collisions. See setRespectPrevTransform().

hasCollider(collider: NodePath)bool

Returns true if the indicated node is current in the set of nodes that will be tested each frame for collisions into other objects.

hasRecorder()bool

Returns true if the CollisionTraverser has a CollisionRecorder object currently assigned, false otherwise.

hideCollisions()None

Undoes the effect of a previous call to showCollisions().

output(out: ostream)None
property recorderCollisionRecorder
Getter

Returns the CollisionRecorder currently assigned, or NULL if no recorder is assigned.

Setter

Uses the indicated CollisionRecorder object to start recording the intersection tests made by each subsequent call to traverse() on this object. A particular CollisionRecorder object can only record one traverser at a time; if this object has already been assigned to another traverser, that assignment is broken.

This is intended to be used in a debugging mode to try to determine what work is being performed by the collision traversal. Usually, attaching a recorder will impose significant runtime overhead.

This does not transfer ownership of the CollisionRecorder pointer; maintenance of that remains the caller’s responsibility. If the CollisionRecorder is destructed, it will cleanly remove itself from the traverser.

removeCollider(collider: NodePath)bool

Removes the collider (and its associated handler) from the set of CollisionNodes that will be tested each frame for collisions into other objects. Returns true if the definition was found and removed, false if it wasn’t present to begin with.

property respect_preV_transformbool
Getter

Returns the flag that indicates whether the prev_transform stored on a node is respected to calculate collisions. See setRespectPrevTransform().

Setter

Sets the flag that indicates whether the prev_transform stored on a node (as updated via set_fluid_pos(), etc.) is respected to calculate collisions. If this is true, certain types of collision tests will be enhanced by the information about objects in motion. If this is false, objects are always considered to be static. The default is false.

property respect_prev_transformbool
Getter

Returns the flag that indicates whether the prev_transform stored on a node is respected to calculate collisions. See setRespectPrevTransform().

Setter

Sets the flag that indicates whether the prev_transform stored on a node (as updated via set_fluid_pos(), etc.) is respected to calculate collisions. If this is true, certain types of collision tests will be enhanced by the information about objects in motion. If this is false, objects are always considered to be static. The default is false.

setRecorder(recorder: CollisionRecorder)None

Uses the indicated CollisionRecorder object to start recording the intersection tests made by each subsequent call to traverse() on this object. A particular CollisionRecorder object can only record one traverser at a time; if this object has already been assigned to another traverser, that assignment is broken.

This is intended to be used in a debugging mode to try to determine what work is being performed by the collision traversal. Usually, attaching a recorder will impose significant runtime overhead.

This does not transfer ownership of the CollisionRecorder pointer; maintenance of that remains the caller’s responsibility. If the CollisionRecorder is destructed, it will cleanly remove itself from the traverser.

setRespectPrevTransform(flag: bool)None

Sets the flag that indicates whether the prev_transform stored on a node (as updated via set_fluid_pos(), etc.) is respected to calculate collisions. If this is true, certain types of collision tests will be enhanced by the information about objects in motion. If this is false, objects are always considered to be static. The default is false.

showCollisions(root: NodePath)CollisionVisualizer

This is a high-level function to create a CollisionVisualizer object to render the collision tests performed by this traverser. The supplied root should be any node in the scene graph; typically, the top node (e.g. render). The CollisionVisualizer will be attached to this node.

traverse(root: NodePath)None

Perform the traversal. Begins at the indicated root and detects all collisions with any of its collider objects against nodes at or below the indicated root, calling the appropriate CollisionHandler for each detected collision.

write(out: ostream, indent_level: int)None