{{tag>dragonscript behavior}}
<WRAP youarehere>
[[:start|Start Page]] >> [[main|DragonScript Scripting Language]] >> [[dragengine:modules:dragonscript:abstractions|Abstraction Layers: How you want to build your Game]] >> [[dragengine:modules:dragonscript:behavior_elements|Behavior Elements]] >> **ECBehaviorColliderAI**
</WRAP>

  * [[behaviors_use_cases|Behaviors Explained: By Use-Case]]
  * [[behaviors_a_to_z|Behaviors Explained: From A to Z]]

====== ECBehaviorColliderAI ======

Behavior element behavior adding collider support suitable for actor AI.

ECBehaviorColliderAI adds a collider which is useable for actor AI usage. This collider is not linked to [[behavior_component|ECBehaviorComponent]] but instead creates a ColliderVolume. The shape of the collider can be set manually or obtained from Rig resources. Using shapes from rig resources is usually the simpler way while creating shapes allows for greater flexibility. Otherwise the classes behave similar.

ECBehaviorColliderAI requires [[behavior_collider|ECBehaviorCollider]]. Do not use this behavior if other behaviors try to move the [[behavior_collider|ECBehaviorCollider]]. Doing so can produce strange results. Apply velocities and changes to the AI collider.

In contrary to [[behavior_collider|ECBehaviorCollider]] this behavior does synchronize position with the element position but not vice versa. Actors typically have complex requirements on how their AI collider can move including projecting down to the ground after physics processing has finished. Behaviors suitable for managing collider AI typically update the AI collider velocities during think() and update element position and orientation from AI collider during postThink().

See also:
  * [[gamedev:colliders|Colliders]]
====== Instance Counts ======
This behavior can be used only once on an element.

====== Element Class Properties ======
Element class properties have the prefix ''colliderAI.'' .

====== Events ======

This behavior has these events:

===== collisionResponse =====

Collision detected.

===== canHitCollider =====

Collision between colliders is possible. Only send if callback is enabled in collider AI. Stops after the first listener returning false. All listeneres added after this listener will not be called.

===== colliderChanged =====

Collider changed.

====== Behavior Tree Actions ======

This behavior adds these behavior tree actions if behavior tree is present.

===== colliderAI.set =====

Set one or more collider ai parameters.

^Parameter^Value^Description^
|enabled|''true'', ''false''|Enable collider|
|gravity|vector3|Set gravity|
|shape|''humanoid''|Set collider shape. Requires additional parameters|
|shape.radius|float|Set radius in meters of humanoid shape|
|shape.height|float|Set height in meters of humanoid shape|

This is an example of using this action:
<code xml>
<action name='colliderAI.set'>
  <parameter name='shape'>humanoid</parameter>
  <parameter name='shape.radius'>0.3</parameter>
  <parameter name='shape.height'>1.8</parameter>
</action>
</code>

===== colliderAI.update =====

Update collider ai.

^Parameter^Value^Description^
|gravity.apply| |Apply gravity to linear velocity of collider|
|geometryFromCollider| |Set element position and orientation from collider|
|stop.turning| |Clear angular velocity of collider|
|stop.moving| |Clear linear velocity of collider|

This is an example of using this action:
<code xml>
<action name='colliderAI.set'>
  <parameter name='gravity.apply'/>
</action>
</code>

===== colliderAI.collision =====

Handle collisions.

^Parameter^Value^Description^
|stop| |Stop collider from moving. Prevents any further collision in this frame update.|
|sliding| |Applies sliding collision response|

This is an example of using this action:
<code xml>
<action name='colliderAI.collision'>
  <parameter name='sliding'/>
</action>
</code>

===== colliderAI.check =====

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

^Parameter^Value^Description^
|enabled|''true'', ''false''|Collider is enabled|
|wait| |If present action returns BTResult.running instead of BTResult.failed to wait until the checks are all fulfilled|

This is an example of using this action:
<code xml>
<sequence>
  <action name='colliderAI.check'>
    <parameter name='enabled'>true</parameter>
  </action>
  <!-- actions here run only if collider ai is enabled -->
</sequence>
</code>

====== Behavior Tree Conditions ======

This behavior adds these behavior tree conditions if behavior tree is present.

===== colliderAI.check =====

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

^Parameter^Value^Description^
|colliderAI.enabled|''true'', ''false''|Collider is enabled|

This is an example of using this condition:
<code xml>
<action name='myAction' id='doing something'>
  <parameter name='colliderAI.enabled'>true</parameter>
  <condition>colliderAI.check</condition>
</action>
</code>

====== State Machine Actions ======

Same as [[#behavior_tree_actions|Behavior Tree Actions]].

====== State Machine Conditions ======

Same as [[#behavior_tree_conditions|Behavior Tree Conditions]].

====== State Machine Events ======

This behavior sends no state machine events.

====== Required Behaviors ======

  * [[behavior_collider|ECBehaviorCollider]]

====== Optional Behaviors ======

  * [[behavior_behaviortree|ECBehaviorBehaviorTree]]: Add actions and conditions for behavior trees to use.
  * [[behavior_statemachine|ECBehaviorStateMachine]]: Add actions and conditions for state machine to use and events to send to the state machine.

====== Persistency ======

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

====== API Documentation ======

#@LinkApiDocDEDS2_HTML~classDragengine_1_1Scenery_1_1ECBehaviorColliderAI.html,ECBehaviorColliderAI~@#.

Since DragonScript Module Version ''1.0''

====== Use Cases ======

  * Allow actor to style his player actor using custom colors for individual body parts.
  * Create variations of NPCs by adding color slots that can be modified in XML Element Classes or using Stub Properties.

====== Element Class Example ======

This example defines an element which contains a resources.

<code>
class MyElement extends BehaviorElementClass
  public var ECBehaviorComponent component
  public var ECBehaviorCollider collider
  public var ECBehaviorColliderAI colliderAI
  func new()
    component = ECBehaviorComponent.new(this, null)
    collider = ECBehaviorCollider.new(this, component)
    colliderAI = ECBehaviorColliderAI.new(this, collider)
  end
end
</code>

====== Behavior Factory ======

Using element class supporting adding behaviors the behavior can be added like this:
<code xml>
<?xml version='1.0' encoding='UTF-8'?>
<elementClass name='MyClass' class='GenericBehaviorElement'>
  <behavior type='ECBehaviorComponent'/>
  <behavior type='ECBehaviorCollider'/>
  
  <behavior type='ECBehaviorColliderAI'>
    <!-- optional: set collision filter. default value '3:0 1 2 3 4' which means
                   category BaseGameApp.CollisionFilterBit.actorAI
                   filter BaseGameApp.CollisionFilterBit.geometry,
                          BaseGameApp.CollisionFilterBit.dynamic,
                          BaseGameApp.CollisionFilterBit.actorAI,
                          BaseGameApp.CollisionFilterBit.trigger.
                   format is '', 'category' or 'category:filter' where category and filter
                   are a list of bits to set. -->
    <string name='collisionFilter'>3:0 1 2 3 4</string>
    
    <!-- optional: use behavior tree with id instead of empty string -->
    <string name='behaviorTree'>second</string>
    
    <!-- optional: use state machine with id instead of empty string -->
    <string name='stateMachine'>second</string>
    
    <!-- set element properties. omit property prefix if used inside behavior tag -->
    <string name='.name'>value</string>
  </behavior>
</elementClass>
</code>

====== Live Examples ======

  * [[https://github.com/LordOfDragons/deexamples|DEExamples Repository]]