Crate sensehat_screen

A Rust library for the Raspberry Pi Sense HAT LED Screen

The Raspberry Pi Sense HAT has an 8×8 RGB LED matrix that provides its own driver for the Linux framebuffer.

This library provides a thread-safe, strong-typed, high-level API for the LED matrix, treating it as you would any other screen on a Linux box.

For examples, please check the examples/ folder in the source code.

Basics

• Screen offers a high-level API for the LED Matrix.

  Internally, it stores a PixelFrame meant to be rendered on the LED Matrix.

  With the linux-framebuffer feature, enabled by default, Screen will have two methods:

  1. Screen::open which opens the framebuffer file-descriptor given as the only argument.

  2. Screen::write_frame which takes a &FrameLine and writes the raw bytes onto the framebuffer, effectively displaying the PixelFrame on the LED Matrix.

• PixelFrame is a collection of 64 PixelColor, representing the 8-row by 8-column LED Matrix.

• PixelColor is a 24-bit representation of an RGB color, encoded in three bytes.

Low-level constructs

• Rgb565 is a 16-bit representation of an RGB color, encoded in two bytes. This is the format. Rgb565 converts into/from PixelColor. supported by the LED Matrix’s framebuffer device.
• FrameLine is the raw-byte rendering of the PixelFrame, properly encoded and ready to be written into the framebuffer device.

Frame operations

• Rotate

  Requires feature = "rotate", which is enabled by default.

  Rotate the PixelFrame by Rotate::None, Rotate::Ccw90, Rotate::Ccw180, or Rotate::Ccw270, that correspond to a counter-clockwise angle of 0°, 90°, 180°, and 270°, respectively.

• Offset

  Requires feature = "offset", which is enabled by default.

  Offset the PixelFrame by Offset::left(n), Offset::right(n), Offset::bottom(n), or Offset::top(n), where n is an integer between in the 0..=8 range.

  Offset with a value of n = 0, return a clone of the PixelFrame.

  Offset with a value of n = 8, return a PixelFrame offset out of view, represented with black pixels (LEDs are off).

• Clip

  Requires feature = "clip", which is enabled by default.

  Creates a clip of two PixelFrames, by defining an Offset. See the clip documentation for more details.

Re-exports

• pub extern crate framebuffer;
• pub use self::color::BackgroundColor;
• pub use self::color::PixelColor;
• pub use self::color::StrokeColor;
• pub use self::fonts::font_to_frame;
• pub use self::fonts::font_to_pixel_frame;
• pub use self::fonts::FontCollection;
• pub use self::fonts::FontString;
• pub use self::fonts::FONT_COLLECTION;
• pub use self::fonts::FONT_COLLECTION;
• pub use self::fonts::FONT_HASHMAP;
• pub use self::fonts::FONT_HASHMAP;
• pub use self::frame::clip::Clip;
• pub use self::frame::Offset;
• pub use self::frame::rotate::Rotate;
• pub use self::frame::FrameLine;
• pub use self::frame::PixelFrame;
• pub use self::screen::Screen;
• pub use self::scroll::Scroll;

Modules

• color
  RGB color for LED pixels, with RGB565 rendering support.
• error
  Errors for the SenseHat Screen.
• fonts
  8x8 font collection
• frame
  Frames for the LED Matrix screen
• screen
  Framebuffer support for the Sense HAT LED Matrix.
• scroll
  Scrolling for pixel frames on the LED Matrix.