Catlike Coding offers a large number of tutorials by Jasper Flick focusing on various technical aspects of game development. With topics covering everything from basic programming concepts to complex rendering techniques, this is absolutely a collection to keep bookmarked and come back to every now and again to learn something new.
Tutorials are based in Unity, and the basics offer a great introduction to the engine. More complex topics offer a deeper understanding of what Unity can do and how it does it, and many focus on topics useful to any engine or programming language.
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