Troubleshooting with log messages
If (and when) an error occurs while developing or running your Unity project, the first thing you must do is consult the Console window for messages. The Console window is where you'll find all kinds of messages including asset import warnings, compiler errors, runtime errors in play mode, build problems when you Build And Run, and others. Compiler errors (such as coding syntax errors) may prevent the scene from running at all (and the Play button will become disabled).
There are three levels of console messages: Info, Warning (shown in orange), and Error (shown in red). You can filter the messages using the toggle buttons in the Console window toolbar, as highlighted in the following screen capture:
Figure 3.1 – The Console window showing a null exception error
Runtime errors, such as the ArgumentNullException error shown in the preceding screenshot, can occur during program execution when you try to use a...
