The GOOF binaries and the src for the Argorha pathfinding can be found there : http://sourceforge.net/project/platform ... _id=202941
The Argorha Pathfinding looks like this:
The main idea of this pathfinding is to put together all the areas where an actor can move. A freely movable area is called a sector. Having sectors is not sufficient; we need to know how to go trough from a sector to another sector. This is defined by portals. These sectors and portals are pre-processed in an editor and they will be used into a game to find the path of an NPC.
In the pictures, the red parts are the sectors and the blue parts are the portals. Once the sectors and portals are generated, we use an algorithm called A* to know where to move. The A* is made between the portals. At the end, a list of AStarNode is returned, from which the actor can move from. If you use just a list of distanced points to move your NPC, it will give the impression that your NPC is a robot. To counter that, in Argorha Pathfinding there are functions to calculate a path between portals: The cardinal splines and Bezier curves. Those functions make sure that the path is always into the sectors. In the pictures, the straight line is yellow, the Bezier curve is green and the cardinal spline is pink.
In GOOF, the pathfinding use a background thread to calculate the data. Perhaps, in GOOF there's a problem with threading; the engine is not threaded. The threading should be put in all GOOF, which it isn't actually. That said, it's working but there's random crash, so the GOOF pathfinding is not meant for production right now. Later it will. Now that it’s using Ogre 1.4.2 it’s way better than when it was under Ogre 1.2.
Due to the problem with threading, the release version is more unstable in term of pathfinding then the debug version. The release version sometimes stops calculating before it has ended or generate bad sectors.
If you wish to just use GOOF, you can deactivate the pathfinding in the options which will make the pathfinding not being used. That way, you won’t have to worry about crashes. The GOOF in the binaries has a lot of instabilities. Coming to my mind right now is painting is not working.
The license for Argorha Pathfinding is LGPL, the same as GOOF.
For more info about the design, you can watch those UML diagrams :
1) http://membres.lycos.fr/bibiteinfo/Imag ... inding.png
2) http://membres.lycos.fr/bibiteinfo/Imag ... inding.png
3) http://membres.lycos.fr/bibiteinfo/Imag ... inding.png
Explanation:
1) This is the main design for the Argorha pathfinding which could be used in any engines.
2) This is the design of pathfinding into GOOF.
3) The interaction between Argorha Pathfinding and GOOF.
Globally, you need to understand that there is the Argorha Pathfinding which do the algorithms and don't know anything about the engine and there is GOOF which uses Argorha Pathfinding to make the pathfinding into GOOF.
I’ve put an online documentation for the pathfinding. It can be found there: http://membres.lycos.fr/bibiteinfo/docPathfinding/
The algorithm is heavily based on this gamasutra article: http://www.gamasutra.com/features/20020405/smith_01.htm
To make the source code working, you need to follow these instructions: http://www.ogre3d.org/wiki/index.php/Ga ... stallation
The only difference is that the ogre version to be taken is v1.4.2
If you speak French, here's my final Cegep report, explaining how the pathfinding works.
http://membres.lycos.fr/fredericjoanis/
On my todo list I’ve got:
- Hierarchical sectors/portals.
- Objects between partitions
- Find and use systems such as doors, ladders, elevators, and teleports.
- Animation and more organic paths
- Advanced GOOF integration. Mouse Integration, UI…
- Save and Load
- Optimization
At last, I hope this is going to be useful to the community. It has been the topic of my internship in winter 2006. When I came back to the code I’ve made at that time, it was so messy I needed to start it all over. Imagine an AI code with calls to graphical engine at each 5 lines. That was almost the case. Now it’s a really cleaner solution. It’s my part time project from that winter until now. Enjoy.
In fact, I'm waiting that version to make cool things with the pathfinding such as having an actor moving around a really complex map. For me the ultimate is when I will see my actor in front of a building and I want it to go to the room 408, so you would click in the editor on the actor, select move and choose the final destination into the room 408. Then you would see the actor just moving inside the building, calling the elevator, waiting for it, going into the elevator, get out of the elevator at the 4th floor, going in front of the door, making the action to open the door and enter the room. With the existing code, i'm not far from this, I just need to be able to do the test case.
