Camera lerp using UI button click not working properly...

Unity Engine
1

I am trying to set up a UI button that, when the user clicks it, it calls to a camera manager that will either lerp from one camera object to another, fade-in/fade-out to another camera object, or just snap to another camera object. The problem I am having is that the co-routine I am calling when the button is clicked does not seem to wait() and allow the lerp to finish. The camera moves a bit when I click but it seems to get interrupted, which is what I thought the co-routine yield would prevent. This is the OnGUI() function code that is in my HUD_mgr script:

void OnGUI(){
    		if(!next_Btn){
    			Debug.LogError("Please assign a texture on the inspector");
    			return;
    		}
    		if(GUI.Button(new Rect(10,10,50,50), next_Btn))
    		{
    			Debug.Log("Clicked the button. Yippee...");
    			camera_Mgr.SendMessage("switchCamera");
    		}
    	}

and here is the switchCamera() function code that is within my Camera_mgr script:

IEnumerator switchCamera(){
    		var duration = Time.deltaTime*3;
    
    		Vector3 pos = main_Camera.transform.position;
    		Quaternion rot = main_Camera.transform.rotation;
    		main_Camera.transform.position = Vector3.Lerp(pos, second_Camera.transform.position, duration);
    		main_Camera.transform.rotation = Quaternion.Lerp(rot, second_Camera.transform.rotation, duration);
    		yield return new WaitForSeconds(duration);
    	}

I am guessing that the fact that OnGUI() is called several times a frame is what is stomping my camera lerp just after it starts. However, if the yield does not work then what should I do? FYI, the snap-to works just fine. It’s the lerp and fade-in/fade-out that do not seem to complete properly.

2

I don’t think that the send message is calling your IEnumerator routine as a routine. try taking out the routine part and just use
StartCoroutine(“switchCameraRoutine”) inside your switchCamera function. I may be wrong on that but thats normally how i do things anyway.
Also your routine isn’t setup to do anything repeatedly. It will perform the actions once then wait for something like 1/20th of a frame.
You’ll probably want to change it to be more like…

bIsTheCameraMovingBoolean = true;
Vector3 pos = main_Camera.transform.position;
Quaternion rot = main_Camera.transform.rotation;
float start = Time.time;
while(Time.time < start + duration)
{
            main_Camera.transform.position = Vector3.Lerp(pos, second_Camera.transform.position, duration);
            main_Camera.transform.rotation = Quaternion.Lerp(rot, second_Camera.transform.rotation, duration);
            yield return new WaitForSeconds(duration);
}
bIsTheCameraMovingBoolean = false;