17cupsofcoffee
commented
3 years ago I don't think I'd want to have third-party UI crates integrated into Tetra directly (there's a lot of them, and everyone has a different favourite one 😄), but making it possible to use them together is definitely something I care about. This was one of the main reasons I added the Mesh API (and why some of the changes to that API were made in 0.6).
Specifically with regards to egui, I've been meaning to play around with that library for a while! If I get it working with Tetra, I will definitely publish an example at the very least - not sure yet if I want to maintain a full crate for it myself, we'll see 😅 I also have some imgui code I need to revisit.
I think for your example, the main bit you're missing is uploading the egui texture data and then binding that to your Tetra mesh - that's where it gets all the fonts and stuff from. egui gives you a Vec of the alpha values for each pixel of the texture, which you'd need to turn into a Vec of RGBA data. You can then upload that via Tetra's Texture::from_rgba constructor/Texture::replace_data method.
In the web backend, they call this function on every paint, if you need an example of the logic. It seems to basically boil down to:
- Check if the texture actually needs updating by checking the version.
- If it does, convert the alpha data into full pixel data.
- Update the texture on the GPU with the new data.
Elinvynia
Summary: The egui UI framework is an extremely ergonomic one, allowing to easily build complex UIs for almost any purpose. I've been trying to integrate it myself into our game, unfortunately seems like it is a tad above my skill level. You can look at my current attempt here: https://github.com/Elinvynia/Enfaria/blob/tetra/enfaria-game/src/egui.rs which produces results looking like this:
Why is this needed? This change doesn't necessarily need to happen in tetra, but could be a separate crate in case users wanted to use something different for handling the UI. I'm happy with any of my code being used for that purpose. But it would certainly make building slightly more complex 2D games much easier and more fun.