How to remove vertex islands from a Polygon Collider 2D?

Questions & Answers
1

Hi all,
I added a Polygon Collider 2D to an object which had a sprite.
Probably with the best intentions, Unity tried its best to create a fitting collider for me.
(The only workaround I have found for this is to copy a Polygon Collider 2D from an Empty Object. Silly, but it works.)
This time, however, I choose to let Unity do it’s thing and edit the collider afterwards. But what if Unity created more ‘islands’ then I want? I seem to have zero control over the number of islands. I cannot create them, but ever worse: I cannot remove vertices after the polygon has been reduced to a triangle.
Who knows a solution? Thanks in advance!

6

Click Edit Collider on the Collider component.
Hover the mouse over the bad vertex.
Hold CMD on Mac, CTRL on windows.
The vertex will become red.
Click.
Gone!

5

You can do this by eleminating “Paths” count:

  • Go to Polygon Collider component

  • Expand “Points”

  • In “Paths” set how many “islands” (size).

2

To answer my own question: I have concluded this is still not possible in Unity 5.2.2.

Edit: Still not supported in 5.4.2f2, but a workaround was suggested by @Okey92.

3

Hey

You might want to check this:
Unity Advanced Polygon Collider

video: Unity Advanced Polygon Collider - Simple and Easy Physics Geometry - YouTube

Maybe this will help you resolve your problems.

Cheers.

4

maybe deleting the path programatically as this code:

using UnityEngine;

// add this script to the gameobject that contains the PolygnCollider2D and then use "run" boolean
// checkbox
[ExecuteInEditMode]
public class NewBehaviourScript : MonoBehaviour {

	public bool run;

	void Start() {
		run = false;
	}

	void Update() {
		if (run == true) {
			PolygonCollider2D poly = GetComponent<PolygonCollider2D>();

			for (int length = poly.pathCount, i = 0; i < length; i++) {
				if (poly.GetPath(i).Length == 3) poly.SetPath(i, null);
			}
			run = false;
		}
	}
}

This deletes isolated triangles, but still existing as a zero item array in the list of paths :frowning: