https://youtu.be/Mckcny6579s
A wolf lives — or dies —by its sense of smell, relying on it to find prey, whether still alive or already dead. We’ve shown the new scent system in previous devblogs, but in the past few months we’ve been overhauling that system to make it more performant (e.g. require less computing power). Our crack Unity developer Nick first tackled the floating scents and then, in March, dove in deep — a lot deeper than any of us expected — to improve the ground scents (the smelly tracks that animals leave as they move around). When playing the game, you first follow airborne scents until you find the ground scent-path that animal feet have left behind, and follow that until you encounter the animal itself. So, both airborne and ground scents are critical elements to make the game fun and playable.
However, having many thousands of these rendering at any given moment when on a scent trail (and especially when following a big herd) was having a serious performance impact, so Nick spent much of March engineering a new system to render these scent particles. What made the task so complicated is that the scents vary by color (indicating species) and alpha value, or transparency (indicating how long since the animal laid down the scent). These variations normally boost the number of draw calls (rendering hits to the graphics card) tremendously, but Nick used a new technique called GPU instancing which allows us to render many thousands of particles at minimal cost.
We think you are going to love the new and improved scent system! As always, thanks for your patience as we get closer to releasing the first episode, Amethyst Mountain, for PC/Mac on Steam and itch.io, as Early Access. That will be followed by Slough Creek some months later, followed by the mobile versions.