Further reading

You can learn more about gizmos at the following links:

• The Unity Gizmos manual entry at https://docs.unity3d.com/ScriptReference/Gizmos.html
• Unity Gizmos tutorial: https://learn.unity.com/tutorial/creating-custom-gizmos-for-development-2019-2

You can learn more about Unity testing at the following links:

• Unity Test Framework manual documentation: https://docs.unity3d.com/Manual/testing-editortestsrunner.html
• Unity Test Framework package documentation: https://docs.unity3d.com/Packages/com.unity.test-framework@1.1/manual/index.html
• Unity Test Framework how-to pages: https://unity.com/how-to/unity-test-framework-video-game-development
• A website for the book The Art of Unit Testing (and lots of other learning resources associated with testing): http://artofunittesting.com/
• A great dual article tutorial about Unity testing by Tomek Paszek from Unity (talking about the old Unity test tools, but most of the content...