Table of Contents
Talk about what a Waypoint Patrol does.
- Node Type: The type of node this is.
- Name: The name of the node, useful for labeling larger trees.
- Repeat: Whether or not this node should repeat.
- Never: The default, the node behaves normally.
- Until Success: The node will continue to repeat until it returns success.
- Until Failure: The node will continue to repeat until it returns failure.
- Forever: The node will continue to repeat forever.
- Debug Break (for Debugging): When checked, if this node is started while running in the editor, playback will be paused.
- Weight (for Random): How likely this node is to be selected when in a random node.
- Starting Priority (for Priority): The initial priority of this node when the Priority node first starts.
- Running Priority (for Priority): The priority of this node while running, refreshed by the Priority node at a set rate.
- Waypoint Route: An expression that evaluates to one of the following:
- The name of a Waypoint Route Rig
- Loop Type: The way the AI will follow the route.
- Ping Pong: The AI will follow the route from start to finish, and then finish to start. It will repeat this forever.
- Loop: The AI will follow the route from start to finish, and then go directly to the start again (as if it was the next node) and continue to the finish again. It will repeat this forever.
- One Way: The AI will follow the route from start to finish, and then return Success.
- Direction: The direction the AI will follow the route.
- Forward: The AI will start at the first node in the route and head towards the last node.
- Reverse: The AI will start at the last node in the route and head towards the first node.
- Move Target Variable: A variable name to store the next position to move to.
Many options on a behavior tree contain expression fields, which allow you to enter an expression instead of a constant value. For instance, an expression field for a target will often take the name of a Navigation Target, a Transform, a GameObject, or Vector3, and an expression allows you to use any of these.
Expression fields will highlight red if there is an error in the expression. For longer expressions it can be easier if you copy the field out into a larger editor.
See Expressions for more information.
Aside from the Never option, repeating has three states it can be in, and is available on most nodes in the behavior tree.
Until Success will cause a node to repeat until it returns Success. This can be used for several purposes: waiting for a Detect to succeed, waiting for a particular Mecanim State to occur, waiting for an Expression to be true, etc.
Until Failure will cause a node to repeat until it returns Failure. Essentially this is used for the same things that Until Success is used for. For instance, if an AI was waiting to detect the player before following them, once they started following you could use another Detect, this one repeating until failure, to determine when the AI has lost the player.
Forever will cause a node to always return Running. Much like its name implies, once this node starts it will continue to run forever. A very common setup for this is in a Parallel, where one node repeats forever and the other one eventually returns Failure or Success. A Constraint is also useful for interrupting a node that is repeating forever.
Talk about normal use
Variables are a very useful part of expressions, but are probably the number one pitfall for three reasons:
- They are case sensitive
- They are created on demand
- They can be used when unassigned
This means if you misspell or incorrectly capitalize your variable, it will treat it as an unassigned new variable and not raise an error of any kind. Keeping your variables names short, concise, and easy to spell will keep this from being too much of a problem.
Another problem this can cause is if you intend to use a string but forget the quotes. If it is a multiple word string it will highlight red, which makes it easy to catch, but if it is a single word string it will be considered a variable instead.
Setting the Waypoint Route
Talk about naming your network and properly using strings as expressions
Waypoint Close Enough Distance
Talk about how to set each waypoint close enough by modifying their size