void RaycastTilePosition(ref Vector3Int worldPos, ref Vector2Int tilePos)
{
if (mapRoot == null)
{
return;
}
Ray ray = Camera.main.ScreenPointToRay(Input.mousePosition);
// get the collision point of the ray with the z = 0 plane
Vector3 worldPoint = ray.GetPoint(-ray.origin.z / ray.direction.z);
worldPos = grid.WorldToCell(worldPoint);
tilePos = PositionMath.GridPositionToTilePosition(worldPos);
}