Editor-only function that Unity calls when the script is loaded or a value changes in the Inspector.
You would usually use this to perform an action after a value changes in the Inspector; for example, making sure that data stays within a certain range. It is not supported for a script to modify values on other scripts than itself.
Note: You cannot reliably perform Camera rendering operations here. Instead, you should add a listener to EditorApplication.update, and perform the rendering during the next Editor Update call.