Collider

A Collider defines collision shape, contact roles, and surface response; configure the Object’s motion in Transform.

Both 2D and 3D Objects can have several named Colliders.

Select the intended Collider when reading or writing a property; Object components explains definitions and instance overrides.

Collision uses Solid, Sensor, and Off in the Object Editor. Solid enables the Collider with Trigger off; Sensor enables both Enabled and Trigger. Off disables the Collider. See Collision and 2D Physics for setup and contact Events.

Defaults are normalized values for an empty component; an Object preset can supply different starting values. “Not stored” means the path is optional or supplied during play. Conditional shape settings appear after you choose that shape.

Writable means exposed for Logic property writes. A No entry can still be editable in the Object Editor. Live contact values are read-only.

For example, writing 4 to self.collider.geometry.transform.size.x sets that Collider’s width to 4 meters on a World Object. Here, collider names the selected Collider.

World lengths use meters; Screen UI lengths use pixels. Rotations use degrees. See Units and Coordinates for the current axis conventions.

Properties

Property and path	Type	Factory default	Behavior	Writable
Enabled (enabled)	boolean	true	Whether this Collider participates in collision detection. Off disables it.	Yes
Trigger (trigger)	boolean	false	True makes an enabled Collider a Sensor. False permits solid response.	Yes
Fixed (fixed)	boolean	Not stored; see behavior	True holds a Physics Object still until Logic writes false. Other motion settings belong to Transform.	Yes
Restitution (restitution)	number	0	Bounce coefficient shown as Bounciness (0–1) in the editor, with stored values clamped to at least 0.	Yes
Friction (friction)	number	0	Surface grip at contact. The editor accepts 0 to 1; stored values are clamped to at least 0.	Yes
Shape (geometry.shape)	text	“box”	Stored choices: box, roundedbox, circle, capsule, ellipse, polygon, model, sprite, or none. The editor offers the current Object’s shape choices.	Yes
Local Position (geometry.transform.position)	vec3	{“x”:0,“y”:0,“z”:0}	Offset from the fixed Object origin in its local coordinate frame.	Yes
Local Position X (geometry.transform.position.x)	number	0	X component of the Collider-local offset.	Yes
Local Position Y (geometry.transform.position.y)	number	0	Offset on Y, using the current project’s axis convention.	Yes
Local Position Z (geometry.transform.position.z)	number	0	Z component of the Collider-local offset; 2D contacts ignore this axis.	Yes
Local Size (geometry.transform.size)	vec3	{“x”:1,“y”:1,“z”:1}	Collider-local extents on all three axes, measured in meters for World Objects and pixels for Screen UI.	Yes
Width (geometry.transform.size.x)	number	1	Extent along the Collider’s local X axis.	Yes
Height (geometry.transform.size.y)	number	1	Y extent of this Collider.	Yes
Depth Size (geometry.transform.size.z)	number	1	Stored Z extent, which never adds depth to a 2D collision shape.	Yes
Local Rotation (geometry.transform.rotation)	vec3	{“x”:0,“y”:0,“z”:0}	Local rotation vector, in degrees. The 2D Collider uses its Z component.	Yes
Local Rotation (geometry.transform.rotation.z)	number	0	Z-axis rotation, in degrees, following the project’s coordinate convention.	Yes
Collision Model (geometry.model)	thing:model	Not stored; see behavior	Model resource selected for the model shape, with a blank reference selecting the Object’s own visual Model.	No
Collision Model Fit (geometry.modelFit)	text	Not stored; see behavior	For the model shape: box means Bounding Box, and mesh means Model Mesh. The normalized default is box.	No
Corner Radius (geometry.cornerRadius)	number	Not stored; see behavior	Rounded-box radius, capped at half the smaller X or Y extent. Other shapes omit this field.	Yes
Rounded Corners (geometry.roundedCorners)	number	Not stored; see behavior	Rounded-box corner bit mask from 0 to 15, omitted for other shapes.	Yes
Polygon Mode (geometry.polygonMode)	text	Not stored; see behavior	For polygon geometry, drawn uses edited vertices and regular uses generated vertices.	Yes
Polygon Sides (geometry.sides)	number	Not stored; see behavior	Regular polygon side count, rounded and clamped to 3 to 32; drawn polygons use their saved vertices.	Yes
Polygon Radius (geometry.regularRadius)	number	Not stored; see behavior	Distance from a regular polygon’s center to each of its vertices.	Yes
Polygon Angle (geometry.regularAngle)	number	Not stored; see behavior	Regular polygon starting angle, in degrees.	Yes
Tags (tags)	text	Not stored; see behavior	Collider Tag labels, read and written as comma-separated Text. They are separate from Object Tags.	Yes
Interaction Filter Mode (interactionFilter.mode)	text	“all”	The editor maps all to Everything, whitelist to Collide Only With, and blacklist to Never Collide With. An empty whitelist accepts no partner.	Yes
Interaction Filter Entries (interactionFilter.objects)	text	[]	Object names or tag:Label entries, supplied as comma-separated Text. An empty blacklist excludes no partner.	Yes
Other Collider (other)	thing:collider	Not stored; see behavior	Read-only partner Collider for this Collider in the active Collision pair; None outside that context or for tile contacts.	No
Touching Colliders (touching)	array	Not stored; see behavior	Read-only array of permitted touching Colliders. Tiles and Colliders on ancestor or descendant Objects are excluded by default.	No
Touching Count (touching.count)	number	Not stored; see behavior	Read-only number of entries in touching; several Colliders on one partner can each add an entry.	No
Blocked Left (blocked.left)	boolean	Not stored; see behavior	Read-only flag for contact on the body’s left side during physics updates.	No
Blocked Right (blocked.right)	boolean	Not stored; see behavior	Reports contact on the body’s right side.	No
Blocked Above (blocked.top)	boolean	Not stored; see behavior	Read-only flag for contact from above; it describes the current physics update.	No
Blocked Below (blocked.bottom)	boolean	Not stored; see behavior	Reports contact below the body during the current physics update.	No