In a previous post, How To Integrate Arduino With Unity, we have shown how data can be sent and received through the serial port. The main problem encountered was dealing with the latency and the delays that communicating across different devices introduces. The solution proposed in that tutorial used a coroutine; decoupling the device communication from the game logic attenuates the problem, but it doesn’t remove it. The main problem is that, despite the name, Unity coroutines are not really executed in parallel with the rest of the game. Unity, by design, is not thread safe. This means that true parallelism is intentionally avoided by the engine, as it could result in race conditions. To solve the problem of the communication between Unity and Arduino, once and for all, we need actual threads.
This post shows how to use arrays and shaders in Unity 5.4. Back in January I already covered this topic in an article called Arrays & shaders: Heatmaps in Unity. My original approach exposed an undocumented feature that allowed to pass arrays to shaders. Since then, Unity 5.4 has introduced proper support in its API. This tutorial replaces the previous article. If you have read the previous tutorial, you do not need any changes to your shader code and you can skip to Step 2.
The previous post in this series, Understanding Deep Dreams, explained what deep dreams are, and what they can be used for. In this second post you’ll learn how to create them, with a step by step guide.