maplibre-rs weekly

maplibre-rs is an upcoming and cross-platform vector map renderer written in Rust. If you want to get in touch with the developers visit the #maplibre:matrix.org chat or join the MapLibre (#maplibre and #maplibre-rs) community within the OpenStreetMap Slack. You can get an invite here.

If you haven’t read the initial news then check it out here. In the past week we continued to work on our collaboration with the University of Applied Sciences and Arts (HES-SO/HEIG-VD), Switzerland. The main focus of the past week was on documentation and redesigning the renderer and the structure of the maplibre-rs library.

In the past week, I extracted the render from Bevy. After some discussions on Github, Slack and Matrix we concluded that writing a renderer specific to maps is the best option. In general, specialized renderers can be optimized better. By implementing a renderer ourselves, we also stay independent of other projects. For example, Bevy is a render engine (renderer + a lot more) for games. That means that features which are important for bevy are most likely not important for maplibre-rs and vice versa. For example, the Bevy renderer does not support a stencil.

Because I’m quite unexperienced in the world of 3D graphics, I dediced to base the renderer on some existing one. The best renderers in the Rust world are currently Bevy and rend3. After evaluating both renderers I decided to go with the Bevy one, because rend3 had usages of `unsafe. Both renderers are based around the idea of a render graph.

The following will summarizes what happened last week on GitHub.

• #99 Postponed: Experimentally render to an Android surface
  Experiment which renders to an Android Surface instead of the whole screen.
• #93 Add Render Graph from Bevy , #94 Experiment: Render Graph from rend3
  Experiment with a new render engine. This will probably define the architecture of maplibre.
• #77 Postponed: Use only non-send futures
  I’m not sure whether Futures should be Send or not.
• #80 Refactor WebWorker pool
  Restructure and optimize WebWorker pool.
• #70 Experimentally add a headless mode
  Experiment with a headless mode.
• #85 Contributors README.md
• #86 Move winit code to maplibre-winit
  Extract winit dependency from main crate.

• #97 Initial start of removing unwrap from a Result type
  Remove .unwrap() from code.
• #88 Postponed: Inspect WASM size
  Optimze WASM size.
• #81 Update license and code of conduct

• #84 Write the Microsoft Windows build documentation
• #87 Improve the Cargo documentation

• #18 Looking forward What’s up in the mapping community?
• #32 Should the map be controlled from rust or from higher level languages? Input handling of maplibre-rs.
• #49 Introduce yourself! Who are you?

Some architectural discussions:

• #75 Usage of bevy game engine
• #60 Requirement of cross-origin isolated
• #83 Potential memory allocation issues on WASM

• @iakev - For resolving .unwrap()s in the code
• neimsaci - For adding contributors to the README