108 lines
4.9 KiB
C#
108 lines
4.9 KiB
C#
using UnityEngine;
|
|
using UnityEngine.AI;
|
|
|
|
namespace BehaviorDesigner.Runtime.Tasks.Movement
|
|
{
|
|
[TaskDescription("Follow the leader using the Unity NavMesh.")]
|
|
[TaskCategory("Movement")]
|
|
[HelpURL("https://www.opsive.com/support/documentation/behavior-designer-movement-pack/")]
|
|
[TaskIcon("9ef93ef9a60e48449a642b1b3b2b577d", "ceded4836fa9bc24f964ec6fadccdc40")]
|
|
public class LeaderFollow : NavMeshGroupMovement
|
|
{
|
|
[Tooltip("Agents less than this distance apart are neighbors")]
|
|
[UnityEngine.Serialization.FormerlySerializedAs("neighborDistance")]
|
|
public SharedFloat m_NeighborDistance = 10;
|
|
[Tooltip("How far behind the leader the agents should follow the leader")]
|
|
[UnityEngine.Serialization.FormerlySerializedAs("leaderBehindDistance")]
|
|
public SharedFloat m_LeaderBehindDistance = 2;
|
|
[Tooltip("The distance that the agents should be separated")]
|
|
[UnityEngine.Serialization.FormerlySerializedAs("separationDistance")]
|
|
public SharedFloat m_SeparationDistance = 2;
|
|
[Tooltip("The agent is getting too close to the front of the leader if they are within the aheadDistance")]
|
|
[UnityEngine.Serialization.FormerlySerializedAs("aheadDistance")]
|
|
public SharedFloat m_AheadDistance = 2;
|
|
[Tooltip("The leader to follow")]
|
|
[UnityEngine.Serialization.FormerlySerializedAs("leader")]
|
|
public SharedGameObject m_Leader;
|
|
|
|
// component cache
|
|
protected Transform m_LeaderTransform;
|
|
protected NavMeshAgent m_LeaderAgent;
|
|
|
|
public override void OnStart()
|
|
{
|
|
m_LeaderTransform = m_Leader.Value.transform;
|
|
m_LeaderAgent = m_Leader.Value.GetComponent<NavMeshAgent>();
|
|
|
|
base.OnStart();
|
|
}
|
|
|
|
// The agents will always be following the leader so always return running
|
|
public override TaskStatus OnUpdate()
|
|
{
|
|
var behindPosition = LeaderBehindPosition();
|
|
// Determine a destination for each agent
|
|
for (int i = 0; i < m_Agents.Length; ++i) {
|
|
// Get out of the way of the leader if the leader is currently looking at the agent and is getting close
|
|
if (LeaderLookingAtAgent(i) && Vector3.Magnitude(m_LeaderTransform.position - m_Transforms[i].position) < m_AheadDistance.Value) {
|
|
SetDestination(i, m_Transforms[i].position + (m_Transforms[i].position - m_LeaderTransform.position).normalized * m_AheadDistance.Value);
|
|
} else {
|
|
// The destination is the behind position added to the separation vector
|
|
SetDestination(i, behindPosition + DetermineSeparation(i));
|
|
}
|
|
}
|
|
return TaskStatus.Running;
|
|
}
|
|
|
|
private Vector3 LeaderBehindPosition()
|
|
{
|
|
// The behind position is the normalized inverse of the leader's velocity multiplied by the leaderBehindDistance
|
|
return m_LeaderTransform.position + (-m_LeaderAgent.velocity).normalized * m_LeaderBehindDistance.Value;
|
|
}
|
|
|
|
// Determine the separation between the current agent and all of the other agents also following the leader
|
|
private Vector3 DetermineSeparation(int agentIndex)
|
|
{
|
|
var separation = Vector3.zero;
|
|
int neighborCount = 0;
|
|
var agentTransform = m_Transforms[agentIndex];
|
|
// Loop through each agent to determine the separation
|
|
for (int i = 0; i < m_Agents.Length; ++i) {
|
|
// The agent can't compare against itself
|
|
if (agentIndex != i) {
|
|
// Only determine the parameters if the other agent is its neighbor
|
|
if (Vector3.SqrMagnitude(m_Transforms[i].position - agentTransform.position) < m_NeighborDistance.Value) {
|
|
// This agent is the neighbor of the original agent so add the separation
|
|
separation += m_Transforms[i].position - agentTransform.position;
|
|
neighborCount++;
|
|
}
|
|
}
|
|
}
|
|
|
|
// Don't move if there are no neighbors
|
|
if (neighborCount == 0) {
|
|
return Vector3.zero;
|
|
}
|
|
// Normalize the value
|
|
return ((separation / neighborCount) * -1).normalized * m_SeparationDistance.Value;
|
|
}
|
|
|
|
// Use the dot product to determine if the leader is looking at the current agent
|
|
public bool LeaderLookingAtAgent(int agentIndex)
|
|
{
|
|
return Vector3.Dot(m_LeaderTransform.forward, m_Transforms[agentIndex].forward) < -0.5f;
|
|
}
|
|
|
|
// Reset the public variables
|
|
public override void OnReset()
|
|
{
|
|
base.OnReset();
|
|
|
|
m_NeighborDistance = 10;
|
|
m_LeaderBehindDistance = 2;
|
|
m_SeparationDistance = 2;
|
|
m_AheadDistance = 2;
|
|
m_Leader = null;
|
|
}
|
|
}
|
|
} |