Grid based A* path finding

        // initialisation
        //
        // create grid
        this.field = new gamvas.AStarGrid(20, 20, this.allowDiagonal, false, gamvas.AStar.STRATEGY_IGNORE_STEPS);

        // fill our grid with random data (< 0 means not walkable, >= 0 is a height field
        for (var y = 0; y < 20; y++) {
            for (var x = 0; x < 20; x++) {
                var v = parseInt(Math.random()*6, 10)-1;
                this.field.setValue(x, y, v);
            }
        }

        // find
        this.currentResult = this.field.find(0, this.startY, 19, this.endY);