Build grid from existing scene for path finder

[TomaszFurca]

Hi! I think about add path finder to my MMOGame. To do that I want use easystar. I looking for rebuild my scene to grid for pathfinder. it is very simple grid multidimensional array with positions. I just need X and Z, because i do not use Y for movement. So my question is... The best function for detect unwalkable fields (meshes like tree, stone, ground Y<0 AND Y >0) is ray? 

How i want to do that:

Get minX, maxX, minZ, maxZ of my ground. Then loop it for every length (1 vec) and check picked mesh or picked position if I pick ground. Then i can recognize unwalkable position and create grid.

 

[ssaket]

Not Sure!  but rather than looping every length(1 vec) as you said, you could loop through other meshes which are inside the scene. And using the boundingBox you can get their min and max X and Z. 
It's won't be accurate since we'll be using boundingBox but definitely fast. 
Let's see what others suggest  

[Spankied]

The best way to do this is to create a navigation mesh on your scene. Then when the user clicks on an area, if the navigation mesh is picked I move the character to that point on the mesh. 

 

    pointerDown(evt){
        let scene = this.scene;
        let pickResult = scene.pick(scene.pointerX, scene.pointerY);
        if (pickResult.pickedMesh == scene.getMeshByName("Navmesh")) {       
            this.player.trigger('move', pickResult.pickedPoint.clone()) //player.action
        } else {
            this.showActionMenu(pickResult.pickedMesh, scene)
        }
    }

 

Heres some resources for baking a nav mesh.

https://docs.blender.org/manual/en/dev/game_engine/physics/types/navigation_mesh.html

https://www.youtube.com/watch?v=aMWeTXL98mM

You can checkout my code here and see demo here. 

Also, Wanadev created a pathfinding library for babylonjs that uses the A* search algorithm to find a path on a nav mesh.