Mirrors and reflective surfaces really seem to be a struggle in modern-day games unless you are using RT, and of course, that has a huge performance penalty so I am quite curious why these techniques that were used in the 90s have fallen out of favour for other techniques that produce significantly worse results visually.
In: Technology
* More memory, and still basically having to process the scene twice. A much better and efficient way would be to re-render the scene again from the POV of the mirror, which would be the same amount of processing, but require less memory and storage.
* “Screen space reflections,” are WAAAY more efficient (compared to older methods, they’re basically free). The amount of situations where you need to have a physically accurate mirror in your scene are actually pretty rare, and the whole reason they were ever done in the first place was usually just to show off the new tech. Once mirror tech became old-hat, level designers stopped going out of their way to design levels that include 1:1 mirrors. Instead, the scenes that _do_ need reflections, cars, large bodies of water, etc. can mostly get by with a mix of SSR or “reflection probes.” SSR isn’t perfect, but for most situations it does what’s needed.
* “Reflection probes,” are even more efficient than SSR, but are pretty rough so are better used on things where the player isn’t going to get a good look at the reflection. It’s basically just a pre-processed image of the scene that gets distorted around the object to look like it’s being reflected. It doesn’t update if the scene changes, and is only “taken,” from a single POV, so close-by objects in the reflection might not line up perfectly (which again, is why it’s not great to rely on reflection probes if you can clearly see the reflection).
Latest Answers