Click and drag to create a path. The blue nodes signify unwalkable nodes. The AStar will try to find the easiest route, sticking to terrain which is the same colour of grey. Obstacles can be generated by pressing a key with the mouse over a square. The path however may overlap these new nodes as thier links will not have been thoroughly stripped as the initial ones are.

Source code: aStarTerrain

Built with Processing and AStar Library