This is an advanced path finding extension. It works by using the A* algorithm to find paths on a Map as a Unit using a Profile. With it you can a lot of cool things like:
Line of sight
Multiple units and maps
Wrapping around maps
Crossing different maps in the one path
Unit sizes
Node land types
Waypoints,
and more.
How it works
Basically the extension is split up into 4 main groups: units; profiles; maps; and transitions (there are also brushes, but they aren't vital). Within each of these 'groups' you can create many different units or profile, maps, etc. Each different item (unit, profile, map, transition, or brush) has a 0-based index within its group. Eg. You can have one unit at index 0, and another at index 1, or one at index 574, etc.
Units
A unit is something that does the actual path finding. A unit has a starting, current, and destination position relating to finding a path.
A unit can also be an obstacle on a map for other units to avoid.
All units need to be assigned a profile to be of any use.
Profiles
A profile is used by a unit to interpret the map(s). A profile contains all the information about the units using the profile, this includes: whether or not to move diagonally; how big the unit is; what to do if the unit's path fails; etc.
A unit is blind without a profile.
A profile is really the most important group.
You may have more than one unit to a profile.
The other major side of profiles is 'Affinity for land types'.
If you set a node on a map to land type "Dirt", say, then you have to tell the profiles about the land type "Dirt". This is called affinity. If you don't give a profile affinity for that land type, then it will be unrecognised by a unit using that profile when finding a path.
There are four parts to affinty for a land type: Weight; line of sight; strength modifier; allowed directions.
The weight of a land type influences how much that land type repels or attracts a unit's path to the nodes of that land type. A lower value attracts, higher value repels.
The line of sight is a true or false thing, if true, then this profile sees this land type as a 'line of sight obstacle'.
The strength modifier adjusts the influence a node's strength of this land type has on the final strength, this is explained in more detail elsewhere.
The allowed directions indicate which directions a unit can move to when moving off a land of this type.
There is an action to set all four at once (which is the best way to do it) or you can set each at a time.
Maps
A map is a grid of square nodes of whatever dimensions you want (the smaller the faster). You can set the weight of each node, but instead of doing it directly, you instead do something like this: Set land type at (3,6,"Grass"), which sets the land type at coordinates 3,6 to "Grass"; then when a unit finds a path, it uses its profile's affinity for the Grass land type to read that node. Nodes also have a land type strength, which basically is a multiplier to a profile's weight affinity for that land type. Eg. If that node's strength was 1.5, and a profile's weight affinity for Grass was 100, then the calculated weight from that node would be 150. That is a simple way it calculates calculated/final weight of a node.
Transitions
Transitions are like teleportation devices for units; they provide shortcuts for units when finding a path.
A transition is a point on a map. If a unit decides to use a transition in finding a path (it will decide automatically based on distances, and other things), then its path will head towards that transition and enter it. A second transition must exist for the path to exit from, and then continue on its way to the destination of the path.
So, transitions operate in pairs, though you don't define the pairing.
Transitions must be used if you want a unit's path to start on one map and then end up on another one altogether. If you set up some transitions properly, you can have a path cross many maps in one go.
Brushes
A brush is basically just an image. You can load an image from an external file into a brush, and then use it for setting zones on a map, or use it for a unit's obstacle-to-others effect.
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