I have already implemented RTC in Javascript, so it felt natural to also tackle that challenge while learning Rust.
I have since found @MrJakob's Youtube series and companion Github repo where he does the same, and I have viewed his content sequentially after first implementing it myself. Secondly, after being stuck for a while on a few select conundrums, I have gone and done it "his way". But for the most part, I have done my own thing, and I'm sure there are much to be desired in optimalization of the code. That is part of the challenge.
As I have now just reached the "Putting it together" part in Chapter 5, where we for the first time actually render something, I was amazed at the speed of Rust. When I did this challenge in Javascript, the very first render took a good 149 seconds to finish. I was able to quickly get that down to 12.9 seconds by replacing the generic arrays with Float32Array that only takes 32-bit floats as values, at the cost of some functionality.
For comparison, that JS code renders on my current hardware in about 50 seconds, so use that as a baseline. When I came to chapter 5 with Rust, the initial debug-profile test render finished in... *drum roll* 700 ms!
Then I decided to go where JS cannot; compilation optimized for release! The Release build of this code renders in 20 ms. Now that's progress!
If you peruse this code and find room for improvement (which is inevitable), please let me know via an Issue, and let us discuss the matter. I'm doing this to learn Rust from basics, so I will want to understand the full rationale behind the change.