Interface IAstarAI

bool canMove

Enables or disables movement completely.

If you want the agent to stand still, but still react to local avoidance and use gravity: use isStopped instead.

This is also useful if you want to have full control over when the movement calculations run. Take a look at MovementUpdate

bool canSearch

Enables or disables recalculating the path at regular intervals.

Setting this to false does not stop any active path requests from being calculated or stop it from continuing to follow the current path.

Note that this only disables automatic path recalculations. If you call the SearchPath() method a path will still be calculated.

Vector3 desiredVelocity

Velocity that this agent wants to move with.

Includes gravity and local avoidance if applicable. In world units per second.

Vector3 desiredVelocityWithoutLocalAvoidance

Velocity that this agent wants to move with before taking local avoidance into account.

Includes gravity. In world units per second.

Setting this property will set the current velocity that the agent is trying to move with, including gravity. This can be useful if you want to make the agent come to a complete stop in a single frame or if you want to modify the velocity in some way.

// Set the velocity to zero, but keep the current gravity
var newVelocity = new Vector3(0, ai.desiredVelocityWithoutLocalAvoidance.y, 0);

ai.desiredVelocityWithoutLocalAvoidance = newVelocity;


If you are not using local avoidance then this property will in almost all cases be identical to desiredVelocity plus some noise due to floating point math.

Vector3 destination

Position in the world that this agent should move to.

If no destination has been set yet, then (+infinity, +infinity, +infinity) will be returned.

Note that setting this property does not immediately cause the agent to recalculate its path. So it may take some time before the agent starts to move towards this point. Most movement scripts have a repathRate field which indicates how often the agent looks for a new path. You can also call the SearchPath method to immediately start to search for a new path. Paths are calculated asynchronously so when an agent starts to search for path it may take a few frames (usually 1 or 2) until the result is available. During this time the pathPending property will return true.

If you are setting a destination and then want to know when the agent has reached that destination then you could either use reachedDestination (recommended) or check both pathPending and reachedEndOfPath. Check the documentation for the respective fields to learn about their differences.

IEnumerator Start () {
ai.destination = somePoint;
// Start to search for a path to the destination immediately
ai.SearchPath();
// Wait until the agent has reached the destination
while (!ai.reachedDestination) {
yield return null;
}
// The agent has reached the destination now
}
IEnumerator Start () {
ai.destination = somePoint;
// Start to search for a path to the destination immediately
// Note that the result may not become available until after a few frames
// ai.pathPending will be true while the path is being calculated
ai.SearchPath();
// Wait until we know for sure that the agent has calculated a path to the destination we set above
while (ai.pathPending || !ai.reachedEndOfPath) {
yield return null;
}
// The agent has reached the destination now
}


Vector3 endOfPath

End point of path the agent is currently following.

If the agent has no path (or it might not be calculated yet), this will return the destination instead. If the agent has no destination it will return the agent's current position.

The end of the path is usually identical or very close to the destination, but it may differ if the path for example was blocked by a wall so that the agent couldn't get any closer.

This is only updated when the path is recalculated.

bool hasPath

True if this agent currently has a path that it follows.

float height

Height of the agent in world units.

This is visualized in the scene view as a yellow cylinder around the character.

This value is currently only used if an RVOController is attached to the same GameObject, otherwise it is only used for drawing nice gizmos in the scene view. However since the height value is used for some things, the radius field is always visible for consistency and easier visualization of the character. That said, it may be used for something in a future release.

bool isStopped

Gets or sets if the agent should stop moving.

If this is set to true the agent will immediately start to slow down as quickly as it can to come to a full stop. The agent will still react to local avoidance and gravity (if applicable), but it will not try to move in any particular direction.

The current path of the agent will not be cleared, so when this is set to false again the agent will continue moving along the previous path.

This is a purely user-controlled parameter, so for example it is not set automatically when the agent stops moving because it has reached the target. Use reachedEndOfPath for that.

If this property is set to true while the agent is traversing an off-mesh link (RichAI script only), then the agent will continue traversing the link and stop once it has completed it.

The steeringTarget property will continue to indicate the point which the agent would move towards if it would not be stopped.

float maxSpeed

Max speed in world units per second.

NativeMovementPlane movementPlane

The plane the agent is moving in.

This is typically the ground plane, which will be the XZ plane in a 3D game, and the XY plane in a 2D game. Ultimately it depends on the graph orientation.

If you are doing pathfinding on a spherical world (see Spherical Worlds), the the movement plane will be the tangent plane of the sphere at the agent's position.

System.Action onSearchPath

Called when the agent recalculates its path.

This is called both for automatic path recalculations (see canSearch) and manual ones (see SearchPath).

bool pathPending

True if a path is currently being calculated.

Vector3 position

Position of the agent.

In world space.

If you want to move the agent you may use Teleport or Move.

float radius

Radius of the agent in world units.

This is visualized in the scene view as a yellow cylinder around the character.

Note that this does not affect pathfinding in any way. The graph used completely determines where the agent can move.

bool reachedDestination

True if the ai has reached the destination.

This is a best effort calculation to see if the destination has been reached. For the AIPath/RichAI scripts, this is when the character is within AIPath.endReachedDistance world units from the destination. For the AILerp script it is when the character is at the destination (±a very small margin).

This value will be updated immediately when the destination is changed (in contrast to reachedEndOfPath), however since path requests are asynchronous it will use an approximation until it sees the real path result. What this property does is to check the distance to the end of the current path, and add to that the distance from the end of the path to the destination (i.e. is assumes it is possible to move in a straight line between the end of the current path to the destination) and then checks if that total distance is less than AIPath.endReachedDistance. This property is therefore only a best effort, but it will work well for almost all use cases.

Furthermore it will not report that the destination is reached if the destination is above the head of the character or more than half the height of the character below its feet (so if you have a multilevel building, it is important that you configure the height of the character correctly).

The cases which could be problematic are if an agent is standing next to a very thin wall and the destination suddenly changes to the other side of that thin wall. During the time that it takes for the path to be calculated the agent may see itself as alredy having reached the destination because the destination only moved a very small distance (the wall was thin), even though it may actually be quite a long way around the wall to the other side.

In contrast to reachedEndOfPath, this property is immediately updated when the destination is changed.

IEnumerator Start () {
ai.destination = somePoint;
// Start to search for a path to the destination immediately
ai.SearchPath();
// Wait until the agent has reached the destination
while (!ai.reachedDestination) {
yield return null;
}
// The agent has reached the destination now
}


bool reachedEndOfPath

True if the agent has reached the end of the current path.

Note that setting the destination does not immediately update the path, nor is there any guarantee that the AI will actually be able to reach the destination that you set. The AI will try to get as close as possible. Often you want to use reachedDestination instead which is easier to work with.

It is very hard to provide a method for detecting if the AI has reached the destination that works across all different games because the destination may not even lie on the navmesh and how that is handled differs from game to game (see also the code snippet in the docs for destination).

float remainingDistance

Approximate remaining distance along the current path to the end of the path.

The RichAI movement script approximates this distance since it is quite expensive to calculate the real distance. However it will be accurate when the agent is within 1 corner of the destination. You can use GetRemainingPath to calculate the actual remaining path more precisely.

The AIPath and AILerp scripts use a more accurate distance calculation at all times.

If the agent does not currently have a path, then positive infinity will be returned.

Quaternion rotation

Rotation of the agent.

In world space.

Vector3 steeringTarget

Point on the path which the agent is currently moving towards.

This is usually a point a small distance ahead of the agent or the end of the path.

If the agent does not have a path at the moment, then the agent's current position will be returned.

bool updatePosition

Determines if the character's position should be coupled to the Transform's position.

If false then all movement calculations will happen as usual, but the GameObject that this component is attached to will not move. Instead, only the position property will change.

This is useful if you want to control the movement of the character using some other means, such as root motion, but still want the AI to move freely.

bool updateRotation

Determines if the character's rotation should be coupled to the Transform's rotation.

If false then all movement calculations will happen as usual, but the GameObject that this component is attached to will not rotate. Instead, only the rotation property will change.

This is particularly useful for 2D games where you want the Transform to stay in the same orientation, and instead swap out the displayed sprite to indicate the direction the character is facing.

Vector3 velocity

Actual velocity that the agent is moving with.

In world units per second.