Choose Top from 2D Pile

Questions & Answers
1

I am using Unity 5 and making a 2D game in which many sprites will be stacked on top of each other and can then be moved by dragging. Sometimes when the users goes to drag from a pile, ones that aren’t on the top are dragged instead. Is there any way to make sure that the one that is dragged is the one on top? Thanks

2

Hi,

Apply your script on the container of your 2D pile and use transform.GetChild();. Index can ben known with transform.childCount !

  • If the top of your pile is the first child in the hierarchy, use transform.GetChild(0);
  • If the top is the last child, use transform.GetChild(transform.childCount - 1);
3

Use RayCast2DAll and sort the array of hits by distance.

using System.Linq;

RaycastHit2D[] hits = Physics2D.RaycastAll(ray.origin, ray.direction, Mathf.Infinity, layerMask, -Mathf.Infinity, Mathf.Infinity).OrderBy(h=>h.distance).ToArray();

Now you can loop through the array and the first element will always be the closest hit (meaning: the one on top).