Make array of object based on position

Unity Engine
1

Hey guys, I’m attempting to make a simple array of objects based on their x and y position. Been having some brain farts back and forth so figured I’d take a stab on here.

Their positions are not snapped to a grid, so I’m unable to use their transform position values. What’s the best way to fill the array based on position relative to one another?

Thanks!

2

Unless the positions don’t have an one to one relation with int pairs you can’t. At least I can’t think of a viable way to do this.
Question is why, given the lack of absolute positions?

3

Well they have a relation, as it will be a grid of objects, just their positions are dynamic and wont be round or reliable.

Their relationship to eachother would, though.

4

Well as mentioned you need an one to one relationship between indexes and positions.

Something like this for example.

Vector2Int GetObjectsTileCoords(Vector3 objPos, float tileSize)
{
var xIndex = Mathf.FloorToInt(objPos.x/ tileSize);
var yIndex = Mathf.FloorToInt(objPos.y/ tileSize);
return new Vectror2Int(xIndex, yIndex);
}
5

This is what I was initially thinking, but my grid objects can be less than a unit in size: IE I could have one at (1x,1y) another at (1.2,1.2) then (1.4,1.4). Wanting to sort that to [1,1][1,2][1,3]

With dynamic starting sizes, though. So that same grid could be (1x,1y) (1.4,1.4) (1.8,1.8)

I dunno I’m all over the place I may need to rethink things :slight_smile:

6

Just did this last weekend, made a grid of enemies in the X/Z plane. Here’s the grid maker:

    void CreateEnemyGrid( Transform grid, int across, int down)
    {
        var xSpacing = grid.localScale.x;
        var zSpacing = grid.localScale.z;

        for (int j = 0; j < down; j++)
        {
            for (int i = 0; i < across; i++)
            {
                Vector3 pos = grid.position + grid.right * i * xSpacing + grid.forward * j * zSpacing;

                MakeFreshDudeAt(pos);  // you supply
            }
        }
    }

Pass in the Transform of where you want the (0,0) guy to be.

Set the scale of that Transform to X and Z being the spacing in X and Z

Set the rotation of the Transform to how you want to align it.

Call the method like so:

        CreateEnemyGrid(
            rootOfFormation,
            8,
            3);

Could be trivially extended:

  • make 3 nested loops to have a 3D formation
  • change any of the axes to be something else (like X/Y)
  • pass the rotation into the MakeDude method so he knows which way to face.
  • etc.
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