void UpdateSelectionObjectMaterial()
{
if (gridObject.CanBuild(Vector2.zero) && MoneyController.CanBuy(cost))
{
selection_object.gameObject.GetComponent <Renderer>().material = selectionMaterialValid;
}
else
{
selection_object.gameObject.GetComponent <Renderer>().material = selectionMaterialInvalid;
}
}
