Bad Cost Estimation in node3d

[green7ea]

The cost estimation for a 3D node (getC) uses a g value that is a 3D cost and an h value that is from the 2D A*. The 3D cost is always higher than the 2D cost since it has more restrictions. This encourages the algorithm to plan from an early path which results in a breath first search.

By adding a weight to the value of g in node3d.hpp:

/// get the total estimated cost
float getC() const
{
    return 0.8 * g + h;
}

The results become more interesting:

Left is the original and right is after the change. This isn't a complete fix as making the costs equivalent is hard but improves the behavior a lot.

[karlkurzer]

Hey, thanks for your comment, this is a great idea in general, it is just very much dependend on the environment configuration and I belive that you will violate the admissibility and consistency of the algorithm.