Buoyant

• Buoyant
  • Capabilities
  • Layout and rendering
  • Available render targets
  • Roadmap
  • Usage notes
  • License
  • Contribution

This is a library for writing and rendering SwiftUI-like layouts in Rust, primarily intended for use on embedded systems.

Capabilities

• Embedded / no_std support:
  • Zero heap allocation
  • Minimal memory footprint
• Support for both character-based and pixel-based rendering and layout
• Ability to support a variety of render devices (terminal, framebuffer, SPI display, ...)

Layout and rendering

Layout code is shared across all pixel types. Views produce a layout which can then be rendered to a render target, calling the rendering code specific to the render target's pixel type. This allows creating support for arbitrary render backends.

Available render targets

• embedded-graphics displays, with "native" fonts and colors.
• TextBuffer: A basic fixed-size char buffer. Does not respect graphemes. This is primarily useful for testing and debugging.
• CrossTerm: Renders colored character-pixels to a terminal using the crossterm crate.

Roadmap

Right now, core components exist to build and render a wide variety of basic static views. In the current state, usability far exceeds manual layout using embedded-graphics primitives directly.

These are the currently planned features:

Distinct View and Widget trees

• State management

  • Layout reuse
  • Animation

• Interactivity

  • click/tap routing
  • focus management + keyboard input

Rendering

• Canvas view for arbitrary path/shape/raster drawing
  • The rendering implementation exclusively targets embedded-graphics, but migrating everything to a canvas interface would enable reusing the rendering logic for other backends.
• Shape stroke/fill
• Embedded SPI displays with built-in fonts
• Alpha blending
  • Rendering is currently write-only, enabling framebufferless rendering

Text

• Unicode breaking character support for better text wrapping on less resource-constrained devices.

Usage notes

This project is a work in progress and should not be used in production.

At this point in time, all public API should be considered unstable, and this library does not yet respect SemVer. Yeah I should have started at 0.0.x. Sorry.

License

Licensed under either of

• Apache License, Version 2.0 (LICENSE-APACHE or http://www.apache.org/licenses/LICENSE-2.0)
• MIT license (LICENSE-MIT or http://opensource.org/licenses/MIT)

at your option.

Contribution

Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.