Can Anyone Confirm - Unity calling OnGUI twice per frame?

why would Unity call OnGUI twice pwe frame?

Code (csharp):

1.  
2. function Update() {
3.     print("Update " + Time.frameCount);
4. }
5.  
6. function LateUpdate() {
7.     print("LateUpdate " + Time.frameCount);
8. }
9.  
10.  
11. function OnGUI () {
12.      print("OnGUI " + Time.frameCount);
13. }
14.  

 

OnGUI is called at least twice per frame. First to compute the layout and then to actually draw the GUI. Try to do a

Code (csharp):

1. Debug.Log(Time.frameCount + ": " + Event.current);

To get a better understanding of the call structure.

 

thanks.
perhaps that detail should be added to the documentation? :wink:

 

OnGUI can be called many times per frame. The GUI system does different things when OnGUI gets called - first it does a prepare pass, recording what components are there (so tab order can be figured out, GUILayout positions are calculated, etc). Then it does the actual event processing; MouseDown, MouseUp, KeyDown, KeyUp, Repaint.

to see what it's actually doing, take a look at Event.current.type

 

I came across this because I was trying to figure when the mouse was over a GUI component so I could ignore mouse events on the 3d objects in the background.

I could not find anything that would give me that, the closest was GUIUtility.hotControl.

I had to store the rects of the gui areas to test when the user click with Rect.Contains() to get it to work.

it would be useful if GUIUtility had a flag that would be set when the mouse over a gui element somenthing like GUIUtility.mouseOver or something like that.

 

That is solved in the next Unity release