Class TriangleEdgeCollisionFilter

Namespace

Jitter2.Collision

Assembly

Jitter2.dll

Filters internal edge collisions for TriangleShape geometry. Adjusts collision normals at shared edges to match neighboring triangles, or discards the collision if the normal cannot be resolved. Requires triangle adjacency information; boundary edges (no neighbor) are left unmodified. Back-face collisions are discarded.

public class TriangleEdgeCollisionFilter : INarrowPhaseFilter

Inheritance

object

TriangleEdgeCollisionFilter

Implements

INarrowPhaseFilter

Inherited Members

object.Equals(object)

object.Equals(object, object)

object.GetHashCode()

object.GetType()

object.MemberwiseClone()

object.ReferenceEquals(object, object)

object.ToString()

Properties

AngleThreshold

Gets or sets the angle threshold for determining when two triangle normals are considered identical.

public JAngle AngleThreshold { get; set; }

Property Value

JAngle

The default value is approximately 2.5 degrees.

Remarks

When a collision occurs near an edge, this threshold determines whether the current triangle and its neighbor are treated as coplanar (same normal) or as forming a crease. Coplanar neighbors use simpler normal snapping logic.

This threshold is also used to detect and discard back-face collisions: if the collision normal points within this angle of being anti-parallel to the triangle normal, the collision is filtered out.

EdgeThreshold

Gets or sets the distance threshold for edge collision detection, in world units.

public float EdgeThreshold { get; set; }

Property Value

float

The default value is 0.01 world units.

Remarks

Collision points closer than this distance to a triangle edge are considered edge collisions and may have their normals adjusted or be discarded. Larger values are more aggressive at filtering edges but may incorrectly affect legitimate collisions near triangle boundaries.

ProjectionThreshold

Gets or sets the minimum length of the projected collision normal required to keep the contact.

public float ProjectionThreshold { get; set; }

Property Value

float

The default value is 0.5.

Remarks

When the collision normal is projected onto the plane formed by the triangle normal and its neighbor's normal, a very short projection indicates the collision is occurring along the edge crease itself. Such collisions are discarded as they typically represent internal edge artifacts.

Lower values allow more edge collisions through; higher values are more aggressive at filtering.

Methods

Filter(RigidBodyShape, RigidBodyShape, ref JVector, ref JVector, ref JVector, ref float)

Called for each detected collision with its contact data.

public bool Filter(RigidBodyShape shapeA, RigidBodyShape shapeB, ref JVector pointA, ref JVector pointB, ref JVector normal, ref float penetration)

Parameters

shapeA RigidBodyShape

The first shape in the collision.

shapeB RigidBodyShape

The second shape in the collision.

pointA JVector

Contact point on shape A (modifiable).

pointB JVector

Contact point on shape B (modifiable).

normal JVector

Collision normal from B to A (modifiable).

penetration float

Penetration depth (modifiable).

Returns

bool

true to keep the collision; false to discard it.