RAIN AI motion detection limiting the visual sensor

I have an enemy called TRex that can follow the player with the RAIN package’s built-in visual sensors. Like any TRex, it should not be able to detect the player if the player hasn’t moved in a short amount of time. I have no idea how to begin writing a script for the TRex because the script has to reference the AI’s visual sensor and the player.

A person on reddit gave me an example to initially fix my TRex because it wasn’t following the player.

The code for the AI:

<component version="1.1" type="RAIN.Core.AIRig"><fields><field value="True" type="System.Boolean" id="_showVisual" /><field value="True" type="System.Boolean" id="_useUnityMessages" /><field value="False" type="System.Boolean" id="_useFixedUpdate" /><field type="RAIN.Core.AI" reference="0" id="_ai" /></fields><references><reference type="RAIN.Core.AI" refcount="1" id="0"><field value="True" type="System.Boolean" id="_isActive" /><field type="UnityEngine.GameObject" id="_body" gameobject="0" /><field type="RAIN.Memory.BasicMemory" reference="1" id="_workingMemory" childrenvisible="False" /><field type="RAIN.Minds.BasicMind" reference="2" id="_mind" childrenvisible="False" /><field type="RAIN.Motion.BasicMotor" reference="3" id="_motor" childrenvisible="False" /><field type="RAIN.Animation.BasicAnimator" reference="4" id="_animator" childrenvisible="False" /><field type="RAIN.Navigation.BasicNavigator" reference="5" id="_navigator" childrenvisible="False" /><field type="RAIN.Perception.BasicSenses" reference="6" id="_senses" childrenvisible="True" /><field type="System.Collections.Generic.List" id="_customElements" elementtype="RAIN.Core.CustomAIElement" childrenvisible="False" /></reference><reference type="RAIN.Memory.BasicMemory" refcount="1" id="1"><field type="System.Collections.Generic.List" id="_memoryItems" elementtype="RAIN.Memory.BasicMemory+MemoryItem" /></reference><reference type="RAIN.Minds.BasicMind" refcount="1" id="2"><field type="RAIN.BehaviorTrees.BTAsset" id="_behaviorTreeAsset" gameobject="1" /><field type="System.Collections.Generic.List" id="_behaviorTreeBindings" elementtype="RAIN.BehaviorTrees.BTAssetBinding" /></reference><reference type="RAIN.Motion.BasicMotor" refcount="1" id="3"><field value="6" type="System.Single" id="_speed" /><field value="180" type="System.Single" id="_rotationSpeed" /><field value="0.1" type="System.Single" id="_closeEnoughDistance" /><field value="0.001" type="System.Single" id="_closeEnoughAngle" /><field value="90" type="System.Single" id="_faceBeforeMoveAngle" /><field value="0.5" type="System.Single" id="_stepUpHeight" /><field value="False" type="System.Boolean" id="_allow3DMovement" /><field value="False" type="System.Boolean" id="_allow3DRotation" /><field value="False" type="System.Boolean" id="_allowOffGraphMovement" /></reference><reference type="RAIN.Animation.BasicAnimator" refcount="1" id="4"><field type="System.Collections.Generic.List" id="_animationStates" elementtype="RAIN.Animation.BasicAnimator+BasicAnimatorState" /></reference><reference type="RAIN.Navigation.BasicNavigator" refcount="1" id="5"><field value="False" type="System.Boolean" id="_drawPaths" /><field value="100" type="System.Int32" id="_maxPathfindingSteps" /><field value="0" type="System.Single" id="_maxPathLength" /><field type="System.Collections.Generic.List" id="_graphTags" elementtype="System.String" /></reference><reference type="RAIN.Perception.BasicSenses" refcount="1" id="6"><field type="System.Collections.Generic.List" id="_sensors" elementtype="RAIN.Perception.Sensors.RAINSensor"><field type="RAIN.Perception.Sensors.VisualSensor" reference="7" id="element0" /></field></reference><reference type="RAIN.Perception.Sensors.VisualSensor" refcount="1" id="7"><field value="True" type="System.Boolean" id="_showVisual" /><field value="Sight" type="System.String" id="_sensorName" /><field value="True" type="System.Boolean" id="_isActive" /><field value="0.6,0,0,1" type="UnityEngine.Color" id="_sensorColor" /><field type="UnityEngine.Transform" id="_mountPoint" gameobject="2" /><field value="0,0,0" type="UnityEngine.Vector3" id="_positionOffset" /><field value="0,0,0" type="UnityEngine.Vector3" id="_angleOffset" /><field type="System.Collections.Generic.List" id="_filters" elementtype="RAIN.Perception.Sensors.Filters.RAINSensorFilter" /><field value="90" type="System.Single" id="_horizontalAngle" /><field value="360" type="System.Single" id="_verticalAngle" /><field value="28.63" type="System.Single" id="_range" /><field value="False" type="System.Boolean" id="_canDetectSelf" /><field value="True" type="System.Boolean" id="_lineOfSight" /><field value="512" type="UnityEngine.LayerMask" id="_lineOfSightMask" /></reference><reference type="RAIN.Perception.Sensors.Filters.NearestXFilter" refcount="0" id="8" /></references></component>

Edit: Took out the download link for the example project, even though it was legitimate.

Why not just have a very large trigger space around the T-REX. If the player comes into contact with the trigger then within OnTriggerStay(), if the T-REX is facing the player within a given viewing angle, then fire a Raycast from the eyes to the player, if it hits, then move the T-REX towards the player. Naturally some variation is needed for realism.

Note: Very few people are likely to download a link from a complete stranger with no reputation on this site, for fear of viruses.

It’s a bit of a difficult problem generally, because some part of your game code needs to track movement of objects. If the T-Rex only cares about the player, then it isn’t too bad. In RAIN, you could write a sensor filter that keeps a list of all objects that persist from frame to frame, along with their prior position. If the object change position, then it can be detected. If it doesn’t, it is not returned in the detected list. That could be a bit expensive to compute if your sensor can detect a lot of objects, but won’t be bad if it is limited to just a handful.