Is there a scene setup call or update for editor scripts?

Questions & Answers
1

Problem: I have an editor script that needs to perform checks within the scene, creating/deleting objects in some cases, but I am only able to get the script to execute when the object is selected (OnInspectorGUI). This is problematic however in that it requires selecting the object. I need the script to update automatically regardless of what object is selected.

Question: Is there a method or a hook I can register that will execute my script, for example upon opening a new scene? Or is there an equivalent of the Update() method for editor scripts?

Keep in mind this is all within the editor, not during runtime.

EDIT: Re-opening Question... There's one fatal flaw with using ExecuteInEditMode, and that is that when I go to build the game (for iOS in my case) I get a bunch of "Unknown Identifier" errors for EditorUtility and AssetDatabase. These are necessary for the setup I need to perform. If I move all the code into my editor script, it works great, but there's no hooks for it to be called except when the object is selected. Does anybody know a way around this?

2

at the top of any javascript,

@script ExecuteInEditMode()

and that will tell the script to run like the game was playing. http://unity3d.com/support/documentation/ScriptReference/ExecuteInEditMode.html

3

I was able to work-around this problem using a C# utility file as an interface to the editor functions I need. Since C# supports the preprocessor and Javascript does not, I used it to create functions that strip out functionality at build time.

Below is a simplified version of the script I created:

using System;
using UnityEngine;
#if UNITY_EDITOR
using UnityEditor;
#endif
using System.Collections;

public class EditorSetupUtility {

    public static UnityEngine.Object LoadAssetAtPath(string assetPath, Type type)
    {
        UnityEngine.Object asset = null;
#if UNITY_EDITOR
        asset = AssetDatabase.LoadAssetAtPath(assetPath, type);
#endif
        return asset;
    }
}

And then in my runtime script I'd do something like this:

function Update() {
    if(Application.isEditor && Application.isPlaying) {
        var framePrefab : GameObject = EditorSetupUtility.LoadAssetAtPath("Assets/Prefabs/Frame.prefab", typeof(GameObject)) as GameObject;
        // .. do other stuff ..
    }
}
4

You can use the #if UNITY_EDITOR preprocessor tags in javascript, in case anyone’s wondering :)Here’s some code I wrote to allow resizing over cover points in the inspector in realtime:

@script ExecuteInEditMode()
...
...
#if UNITY_EDITOR
function Update() {
	if (gameObject.transform.localScale.x != width)
		gameObject.transform.localScale.x = width;
	
	
	if (lowCover && gameObject.transform.localScale.y != lowCoverHeight) {
		gameObject.transform.localScale.y = lowCoverHeight;
		gameObject.transform.position.y = 
			gameObject.transform.parent.position.y + (lowCoverHeight/2);
	}
	else if (!lowCover && gameObject.transform.localScale.y != highCoverHeight) {
		gameObject.transform.localScale.y = highCoverHeight;
		gameObject.transform.position.y = 
			gameObject.transform.parent.position.y + (highCoverHeight/2);
	}
}
#endif