Behavior adding support to VR Hand behavior to know what element they are pointing at.

Behavior uses one collider collision test located attached controller collider facing forward.

If hand component is present and a test bone is set the collision test will be attached to the component bone.

By default the test direction is rotated by -45 degrees along the X axis. This accounts for VR hand controllers typically having their Z axis along the grip direction. This causes the point at detection to point 45 degrees upwards. For easier usage rotating the point at detection direction downwards by 45 degrees helps.

By default point-at is disabled for backwards compatibility.

This behavior can be added twice to an element to add support for left and right hand controller. Use the behavior identifier to tell them apart.

Element class properties have the prefix vrHandPointAt. or vrHandPointAt(id). if id is not empty.

Range in meters to test for objects supporting to be pointed at.

• Full name: vrHandPointAt.range or vrHandPointAt(id).range
• Type: float
• Restrictions: At least 0
• Default Value: 2
• Example (*.deeclass):

  <float name='vrHandPointAt(right).range'>3.5</float>

Test origin relative to hand controller coordinate system.

• Full name: vrHandPointAt.origin or vrHandPointAt(id).origin
• Type: 3-component vector
• Default value: (0, 0, 0)
• Example (*.deeclass):

  <vector name='vrHandPointAt(left).origin' x='0' y='0.1' z='0.2'/>

Test rotation in degrees relative to hand controller coordinate system.

• Full name: vrHandPointAt.rotation or vrHandPointAt(id).rotation
• Type: 3-component vector
• Default value: (0, 0, 0)
• Example (*.deeclass):

  <vector name='vrHandPointAt(left).rotation' x='45' y='0' z='0'/>

Name of bone in controller model to attach to or empty string to attach to the controller itself.

• Full name: vrHandPointAt.bone or vrHandPointAt(id).bone
• Type: string
• Default Value: empty string
• Example (*.deeclass):

  <string name='vrHandPointAt(right).bone'>indexFinger</string>

This behavior adds these behavior tree actions if behavior tree is present. If behavior has non-empty identifier replace vrHandPointAt with vrHandPointAt(id).

Update VR hand point-at.

This is an example of using this action:

<action name='vrHandPointAt.set'>
  <parameter name='interactElement.assign'/>
</action>

Check one or more VR hand point-at parameters. Action succeeds if all parameter value matches their respective VR hand point-at parameter otherwise action fails. This action is typically used as first action in a sequence to run the sequence only if a VR hand point-at parameter matches (or not).

This is an example of using this action:

<sequence>
  <action name='vrHandPointAt.check'>
    <parameter name='enabled'>true</parameter>
  </action>
  <!-- actions here run only if VR hand point-at is enabled -->
</sequence>

This behavior adds these behavior tree conditions if behavior tree is present. If behavior has non-empty identifier replace vrHandPointAt with vrHandPointAt(id).

Check one or more VR hand point-at parameters. Conditions returns true if all parameter value match their respective VR hand point-at parameter. This condition is typically used to run an action or sequence of actions as long as VR hand point-at conditions are true.

This is an example of using this condition:

<action name='myAction' id='doing something'>
  <parameter name='vrHandPointAt.enabled'>true</parameter>
  <condition>vrHandPointAt.check</condition>
</action>

Same as Behavior Tree Actions.

Same as Behavior Tree Conditions.

This behavior sends these state machine events. If behavior has non-empty identifier replace vrHandPointAt with vrHandPointAt(id).

VR hand point-at has been enabled.

VR hand point-at has been disabled.

Pointing at an element. Send if pointing at an element when previously not pointing at an element or pointing at a different element.

Not pointing at an element. Send if not pointing at an element when previously has been pointing at an element.

• ECBehaviorVRHand

• ECBehaviorBehaviorTree: Add actions and conditions for behavior trees to use.
• ECBehaviorStateMachine: Add actions and conditions for state machine to use and events to send to the state machine.

This behavior does support element class to be persistable (setPersistable).

ECBehaviorVRHand.

Since DragonScript Module Version 1.7

• Test what objects in the world the player is pointing at

The following example creates an element class with support to test what element the player is pointing at:

class MyElement extends BehaviorElementClass
   public var ECBehaviorVRPlayspace vrPlayspace
   public var ECBehaviorVRHand vrHandRight
   public var ECBehaviorVRHand vrHandLeft
   public var ECBehaviorVRHandPointAt vrRightHandPointAt
   public var ECBehaviorVRHandPointAt vrLeftHandPointAt
   
   public func new()
      // Create playspace
      vrPlayspace = ECBehaviorVRPlayspace.new(this)
      
      // Create hand controllers. The InputDeviceType indicates what device type
      // to monitor. vrRightHand and vrLeftHand can exist only once
      vrHandRight = ECBehaviorVRHand.new(this, vrPlayspace, InputDeviceType.vrRightHand, "right")
      vrHandLeft = ECBehaviorVRHand.new(this, vrPlayspace, InputDeviceType.vrLeftHand, "left")
      
      // Create point at behavior for each hand. By default the test direction
      // is along the controller Z axis. For common controllers this points
      // along the handle direction which is like holding a sword or similar
      vrRightHandPointAt = ECBehaviorVRHandPointAt.new(this, vrRightHand, "right")
      vrLeftHandPointAt = ECBehaviorVRHandPointAt.new(this, vrLeftHand, "left")
      
      // If you have a ECBehaviorCollider in your element class it is a good idea
      // to ignore this collider. This avoids the point hitting the player body
      // or hands.
      
      // vrRightHandPointAt.setIgnoreCollider(collider)
      // vrLeftHandPointAt.setIgnoreCollider(collider)
  end
end

The BaseVRActorClass provides full VR support including ECBehaviorVRHandPointAt for both hands.

Using element class supporting adding behaviors the behavior can be added like this:

<?xml version='1.0' encoding='UTF-8'?>
<elementClass name='MyClass' class='GenericBehaviorElement'>
  <behavior type='ECBehaviorVRPlayspace'/>
  <behavior type='ECBehaviorVRHand' id='right'/>
  <behavior type='ECBehaviorVRHand' id='left'/>
 
  <behavior type='ECBehaviorVRHandPointAt' id='right'>
    <!-- required: use vr hand with id. -->
    <string name='vrHand'>right</string>
 
    <!-- optional: set collision filter. default value '1:0 1 2' which means
                   category BaseGameApp.CollisionFilterBit.dynamic
                   filter BaseGameApp.CollisionFilterBit.geometry,
                          BaseGameApp.CollisionFilterBit.dynamic,
                          BaseGameApp.CollisionFilterBit.actor.
                   format is '', 'category' or 'category:filter' where category and filter
                   are a list of bits to set. -->
    <string name='collisionFilter'>6:0 1 2 3 5</string>
 
    <!-- optional: add behavior trees. default adds all behavior trees. -->
    <list name='behaviorTrees'>
      <string/> <!-- add behavior with empty identifier -->
      <string>default</string> <!-- add behavior with 'default' identifier -->
    </list>
 
    <!-- optional: add state machines. default adds all state machines. -->
    <list name='stateMachines'>
      <string/> <!-- add behavior with empty identifier -->
      <string>default</string> <!-- add behavior with 'default' identifier -->
    </list>
 
    <!-- set element properties. omit property prefix if used inside behavior tag -->
    <string name='.name'>value</string>
  </behavior>
 
  <behavior type='ECBehaviorVRHandPointAt' id='left'>
    ...
  </behavior>
</elementClass>

• DEExamples Repository: ExampleVR project.