Rect.Contains and Rect.Overlap always return true

Question

 using System.Collections;
 using System.Collections.Generic;
 using UnityEngine;
 using UnityEngine.EventSystems;
 
 public class CheckOverlap: MonoBehaviour 
 { 
     RectTransform rectTransform;
     public RectTransform otherRect;
 
     void Start () 
     {
         rectTransform = GetComponent<RectTransform> ();
     }
 
     void Update () 
     {
         if (otherRect.rect.Contains(rectTransform.rect.center))
         {
             print ("Contains");
         }
 
         if (otherRect.rect.Overlaps(rectTransform.rect))
         {
             print ("Overlaps");
         }
     }
 }

..

This is the only code, and the two Rects I'm comparing are newly generated UI Images. One has the script and sets the other as "otherRect".

It just spams "True" regardless of where the Rects are from scene start.

Answer 1

Best Answer

Answer by lassade · Jan 23, 2018 at 03:12 AM

Like I was suspecting the RectTransform.rect is in local space this means that the center will be always Vector3.zero. Try this fucntion:

 Rect GetWorldSapceRect(RectTransform rt)
 {
     var r = rt.rect;
     r.center = rt.TransformPoint(r.center);
     r.size = rt.TransformVector(r.size);
     return r;
 }

Edit: This code does not allow for any kind of rotation between the rectangles since it's an axis aligned structure. To support that kind of thing you may want to use Physics2D to avoid any crazy maths.

Using Colliders2D inside your UI can be tricky but is doable.

Add comment · Show 2 · Share

Tubsiwub · Jan 23, 2018 at 06:25 PM 0

Share

Thanks for the reply. I didn't even think to check for that as it seems incredibly stupid that there would be public access to an object's Rect properties when they will always return zero.

Checking that confirms it, so I'll be using your solution.

Eltayeb · Feb 25, 2021 at 10:09 AM 1

Share

You my friend are legend, you have no idea how much i want to thank you.

Rect.Contains and Rect.Overlap always return true

1 Reply

Your answer

Follow this Question

Related Questions