Narrow Phase: Ray Trace Narrow Phase

The RayTraceNarrowPhase component is a narrow phase component, which is used in a collision pipeline. This method traces a ray for each point in one object following the opposite of the point’s normal up to find a triangle in the other object. Both triangles are tested to evaluate if they are in a colliding state.

It must be used with a TriangleOctreeModel, as an octree is used to traverse the object.

The Algorithm

The CollisionModel at the lowest level is saved, in this case it must be a TriangleOctreeModel. If the octree would not be constructed already, build it. Then, rays are traced against the TriangleOctreeModel. Distances computed with the ray indicates if a collision occurs between the pair of TriangleOctreeModels. Finally, the DetectionOutput vector containing elements of TriangleOctreeModels in collision is returned, as well as the contact points on the triangle of each model.

Example of Usage

This component can be used as follows in XML format:

<FreeMotionAnimationLoop />
<DefaultPipeline depth="15" verbose="0" draw="0" />
<BruteForceBroadPhase name="N2" />
<RayTraceNarrowPhase/>
<MinProximityIntersection name="Proximity" alarmDistance="1.5" contactDistance="1" />
<DefaultContactManager name="Response" response="FrictionContact" />

Colliding objects must have a TriangleOctreeModel:

<TriangleOctreeModel/>