I'd like to remove textures from memory, and fall back on different shaders if I receive the onDidReceiveMemoryWarning from the iOS, but right now I do not see any documentation on how to get that message? I was wondering if anyone has done this or if there is a tool//plugin that could assist with this if Unity does not have native support for this?
There are vague mentions on the forums to check UnitySendMessage in the AppController, but I have no real idea on how to do this.
I found the answer for anyone interested.
In the AppController.mm
Look for the function:
This is the function that is called when your app receives a low memory warning.
Next you must add a UnitySendMessage to your Unity code, so that you can receive the low memory warning message in your Unity code.
So, you must modify the applicationDidReceiveMemoryWarning function by writing this code:
After you add this message call to the AppController.mm file, in your Unity code, add a new file for the class that will be receiving the message. Mine happens to be in C#, but it can be any file type. Mine is MemoyManager.cs.
Then add the code:
This class now receives the message sent from the AppController.mm, and within your own function, mine is ReceivedMemoryWarning, handle how you deal with, free up memory within your game/project.
Also, it's worth mentioning if you want to modify the AppController.mm and have it update automatically in xCode every time, first create a folder in your Assets folder within the Project hierarchy window named "iOS" under the Plugins folder, so the hierarchy directory is Assets/Plugins/iOS. Then drag the AppController.mm file into that folder with your modified code, and Unity will automatically update your changes when it builds to xCode.
I hope that helps for everyone who is looking to do this, whether you're a programmer or not.