getCost
float getCost(int x,
              int y,
              int z,
              int dx,
              int dy,
              int dz)
Get the additional heuristic cost of the given tile. This controls the
 order in which tiles are searched while attempting to find a path to the
 target location. The lower the cost the more likely the tile will
 be searched.
- Parameters:
- x- The x coordinate of the tile being evaluated
- y- The y coordinate of the tile being evaluated
- z- The z coordinate of the tile being evaluated
- dx- The x coordinate of the destination location
- dy- The y coordinate of the destination location
- dz- The z coordinate of the destination location
- Returns:
- The cost associated with the given tile