In Rust, there is none; they're just not ready, and not used either (there are very few full games written in Rust). The Bevy maintainers in particular give very low priority to foundational functionalities (see 1 frame lag and the unusable stages+states), and focus on advanced ones instead.
There aren't so many alternatives actually (SDL is a very valid framework, but it isn't a game engine), and the choice depends on what's your real goal (experiment or develop a real game). In my opinion, if the goal is to produce a real game, for somebody who doesn't have significant experience, documentation (including: availability of books) is the top priority.
There aren't so many alternatives actually (SDL is a very valid framework, but it isn't a game engine), and the choice depends on what's your real goal (experiment or develop a real game). In my opinion, if the goal is to produce a real game, for somebody who doesn't have significant experience, documentation (including: availability of books) is the top priority.