On Wednesday afternoon, Days Gone developer Bend Studios held a Reddit Ask Me Anything. The team’s responses provided a brief but in-depth look at some of the more technical work that went into making Days Gone, including their rendering of eyes—something that the game does so well it’s easy to completely miss.
Luckily, one Reddit user pointed it out, and Graham Aldridge, the game’s lead rendering programmer, divulged the secret. It’s the same thing that keeps our actual eyes from looking strange: tears and dilation.
“Eyes are hard to get right, as it’s all about the subtleties so you don’t notice them. As examples, we have a tear line in our eye rendering—an effect to represent the buildup of liquid between the eye and lower eyelid. It’s a surprisingly difficult effect to render, but without it the character just looks wrong somehow. We have control of this too—it’s surprising how much adjusting the tear line can change your perception of a character. Another subtle example is iris/pupil dilation; we change the size based on how bright the scene is. It’s super subtle but when you see a character in a dark space with a small iris it just feels wrong.”
Again, it’s easy to miss things like this. Many of Days Gone’s real-time cutscenes take place at night or indoors with lots of shadows (another thing the development team put a lot of work into, per the AMA). According to the developers, all of this work exists so things like characters’ eyes aren’t noticed.
The whole AMA is worth reading through for a look at some of the easy-to-miss details in the game. The way weather works, for example, is a wonderfully complex mess (just like real life!) that ties weather conditions to the actual clouds, which move through the world in real time.
It’s always a pleasure to learn about the specific work that goes into a video game, even one that we didn’t particularly gel with. Games are massive, complex things full of hundreds of disparate design ideas—even if the whole doesn’t quite come together, there’s always plenty worth thinking about.