fix dstar

[Ts-sound]

Reference issue

fix #886

What does this implement/fix?

When you modify the map ( add obstacle ) , the untraveled paths are updated ；

[2892510130]

Thanks for your PR, but there is still a little bug here: when your newly added obstacle is too long it will not work. I think the reason is that the initialization of Map is [0 -> 100], so it does not initialize points have negative x coordinate. However the obstacle, ox, have negative value. Maybe we should change the Map initialization code?

[2892510130]

Another question: I read your code, and I find that you rerun the D* in a cloned map. Is it still a D* algorithm? D* should be abled to dynamically find a path based on previous search result, but your dstar2 is a new search without information from a previous search.

[2892510130]

I've fixed the bug, but there's still a problem with the map initialization process (it's not a problem with the algorithm, so I don't want to waste time fixing it, haha). #896