Contact

Introduction

Contact represents the relation between a body part and a contactable object.

Body parts can have multiple bones and sub-parts (e.g. a hand has 1 bone (wrist) and 5 fingers (sub-parts)). Contact stores which bones under this part (bones of part and its sub-parts) are touching or are close to touch (entered).

If ContactDetection module is linked to a hand, it will handle contacts for all bones in that hand including finger bones.

If ContactDetection module is linked to an arm, it will handle contacts for arm's bones, hand bones and finger bones.

If ContactDetection modules is linked to both arm and hand, there will be duplicated contacts for hand and finger bones, which is not recommended.

Variables

Name: Name of the contact. Useful for debugging.

Detector: ContactDetection module which is responsible for updating this contact. This ContactDetection module is linked (as child module) to a body part.

Contactable: ContactableView that represents the object that is being contacted.

Special Parts Touching: How many bones are touching the contactable object and are linked to a part or sub-part that is specially involved in grasping.

Hand, thumb finger and index finger are the 3 parts that are specially involved in grasping.

Type:

• None: 0 bones are entered.

• Entered: At least 1 bone is entered. 0 bones are touching touching.

• Touching: At least 1 bone is touching. Grasping is not detected.

• Grasped: At least 1 bone is touching. Grasping is detected.

Grasping is detected when:

• There are at least 2 parts touching.

• There are at least 2 parts touching that are specially involved in grasping.

• Not all parts that are touching are parts specially involved in grasping.

Entered Time: Elapsed time since at least one bone entered the contactable object.

Touched Time: Elapsed time since at least one bone touched the contactable object.

Grasped Time: Elapsed time since Contact.type became Grasped.

Bones Entered: List of BoneModels that are near the contactable object.

Bones Touching: List of BoneCollisionModels that are touching the contactable object.

ContactDetectionView.contacts returns a list of ContactViews.

BoneCollisionModel

Bone: BoneModel which slave representation performed the contact.

Points: List of ContactPoints retrieved from the collision detection.

ContactView.bonesTouching return a list of BoneCollisionViews.