embedded-graphics 0.6.0-beta.2

Embedded graphics library for small hardware displays
Documentation

Embedded graphics

Embedded-graphics is a 2D graphics library that is focused on memory constrained embedded devices. It contains built in items that make it easy to draw 2D graphics primitives:

  • Primitive shapes with stroke and/or fill
    • Lines
    • Rectangles
    • Circles
    • Triangles
  • Images
    • Built in support for images from raw data
    • Other image formats, like BMP and TGA images, are supported using an external crate
  • Text

A core goal of embedded-graphics is to draw graphics without using any buffers; the crate is no_std compatible and works without a dynamic memory allocator, and without pre-allocating large chunks of memory. To achieve this, it takes an Iterator based approach, where pixel values and positions are calculated on the fly, with the minimum of saved state. This allows the consuming application to use far less RAM at little to no performance penalty.

To support many different kinds of display embedded-graphics doesn't include any drivers directly but provides an API that can be implemented by external crates. The display drivers section contains a list of display drivers with embedded-graphics support. In addition to the drivers for real displays the simulator can be used to test code during development.

Other functions of embedded-graphics are also designed to be extended by the application or other crates. Examples of this are adding support for different image formats or implementing custom Drawable items. The external crates section contains a list of crates that provide reusable extensions to embedded-graphics.

Embedded graphics on real hardware

Documentation

More information and up to date docs can be found on docs.rs.

Getting help/reporting an issue

If you think you've found a bug, or would like to suggest a new feature to add to embedded-graphics, please open an issue.

If you need more deeper/more personalized help, please check out the embedded-graphics Matrix channel.

Additional functions provided by external crates

Note that some of these crates may not support the latest version of embedded-graphics.

If you know of a crate that is not in this list, please open an issue.

Display drivers

  • embedded-graphics-simulator: Simulated display
  • hub75: A rust driver for hub75 rgb matrix displays
  • ili9341: A platform agnostic driver to interface with the ILI9341 (and ILI9340C) TFT LCD display
  • ls010b7dh01: A platform agnostic driver for the LS010B7DH01 memory LCD display
  • sh1106: I2C driver for the SH1106 OLED display
  • ssd1306: I2C and SPI (4 wire) driver for the SSD1306 OLED display
  • ssd1322: Pure Rust driver for the SSD1322 OLED display chip
  • ssd1331: SPI (4 wire) driver for the SSD1331 OLED display
  • ssd1351: SSD1351 driver
  • ssd1675: Rust driver for the Solomon Systech SSD1675 e-Paper display (EPD) controller
  • st7735-lcd: Rust library for displays using the ST7735 driver
  • st7920: ST7920 LCD driver in Rust

Note that some drivers may not support the latest version of embedded-graphics.

There may be other drivers out there we don't know about yet. If you know of a driver to add to this list, please open an issue!

Example

The following example uses the simulator to demonstrate some of the built in drawing functions:

use embedded_graphics::{
    fonts::{Font6x8, Text},
    pixelcolor::BinaryColor,
    prelude::*,
    primitives::{Circle, Rectangle, Triangle},
    style::{PrimitiveStyle, TextStyle},
};
use embedded_graphics_simulator::{
    BinaryColorTheme, OutputSettingsBuilder, SimulatorDisplay, Window,
};

fn main() -> Result<(), std::convert::Infallible> {
    // Create a new monochrome simulator display with 128x64 pixels.
    let mut display: SimulatorDisplay<BinaryColor> = SimulatorDisplay::new(Size::new(128, 64));

    // Create styles used by the drawing operations.
    let thin_stroke = PrimitiveStyle::with_stroke(BinaryColor::On, 1);
    let thick_stroke = PrimitiveStyle::with_stroke(BinaryColor::On, 3);
    let fill = PrimitiveStyle::with_fill(BinaryColor::On);
    let text_style = TextStyle::new(Font6x8, BinaryColor::On);

    let yoffset = 10;

    // Draw an 3px wide outline around the display.
    let bottom_right = Point::zero() + display.size() - Point::new(1, 1);
    Rectangle::new(Point::zero(), bottom_right)
        .into_styled(thick_stroke)
        .draw(&mut display)?;

    // Draw a triangle.
    Triangle::new(
        Point::new(16, 16 + yoffset),
        Point::new(16 + 16, 16 + yoffset),
        Point::new(16 + 8, yoffset),
    )
    .into_styled(thin_stroke)
    .draw(&mut display)?;

    // Draw a filled square
    Rectangle::new(Point::new(52, yoffset), Point::new(52 + 16, 16 + yoffset))
        .into_styled(fill)
        .draw(&mut display)?;

    // Draw a square with a 3px wide stroke.
    Circle::new(Point::new(96, yoffset + 8), 8)
        .into_styled(thick_stroke)
        .draw(&mut display)?;

    // Draw centered text.
    let text = "embedded-graphics";
    let width = text.len() as i32 * 6;
    Text::new(text, Point::new(64 - width / 2, 40))
        .into_styled(text_style)
        .draw(&mut display)?;

    let output_settings = OutputSettingsBuilder::new()
        .theme(BinaryColorTheme::OledBlue)
        .build();
    Window::new("Hello World", &output_settings).show_static(&display);

    Ok(())
}

This example is also included in the simulator crate and can be run using cargo run --example hello-world.

Embedded Graphics Simulator example screenshot

Additional examples can be found in the simulator crate.

Using macros

Embedded graphics defines macros to easily build drawables and styles for primitives and texts:

use embedded_graphics::fonts::Font6x8;
use embedded_graphics::pixelcolor::Rgb565;
use embedded_graphics::prelude::*;
use embedded_graphics::{
    egcircle, egline, egrectangle, egtext, egtriangle, primitive_style, text_style,
};

// Only used for examples - this would be replaced by the driver for your chosen display
use embedded_graphics::mock_display::MockDisplay as Display;

fn main() {
    // Create a display object to draw into
    // This will be whichever display driver you decide to use, like the SSD1306, SSD1351, etc
    let mut display = Display::new();

    // Draw a circle centered at (64, 64) with a radius of 64 and a white 1px stroke
    egcircle!(
        center = (64, 64),
        radius = 64,
        style = primitive_style!(stroke_color = Rgb565::WHITE)
    )
    .draw(&mut display);

    // Draw a 1px thick white line from (64, 64) to (0, 64)
    egline!(
        start = (64, 64),
        end = (0, 64),
        style = primitive_style!(stroke_color = Rgb565::WHITE)
    )
    .draw(&mut display);

    // Draw a 1px red line from (64, 64) to (80, 80)
    egline!(
        start = (64, 64),
        end = (80, 80),
        style = primitive_style!(stroke_color = Rgb565::RED)
    )
    .draw(&mut display);

    // Draw a rectangle from (64, 64) to (80, 80) with a black fill
    egrectangle!(
        top_left = (64, 64),
        bottom_right = (80, 80),
        style = primitive_style!(fill_color = Rgb565::BLACK)
    )
    .draw(&mut display);

    // Print "Hello world!" in a white 6x8 pixel font with the top left corner positioned at (5, 50)
    egtext!(
        text = "Hello world!",
        top_left = (5, 50),
        style = text_style!(font = Font6x8, text_color = Rgb565::WHITE)
    )
    .draw(&mut display);
}

Cargo Features

  • nalgebra_support - use the Nalgebra crate with no_std support to enable conversions from nalgebra::Vector2 to Coord and UnsignedCoord.

Development setup

Minimum supported Rust version

The minimum supported Rust version for embedded-graphics is 1.40.0 or greater. Ensure you have the latest stable version of Rust installed, preferably through https://rustup.rs.

Ubuntu/Linux Mint

# Update to latest stable version of Rust
rustup update

# Ensure rustfmt is installed
rustup component add rustfmt

# Install SDL2 for simulator and PIP to install linkchecker
sudo apt install libsdl2-dev python-pip

# Install linkchecker so doc links can be checked
sudo pip install linkchecker

Attribution

All source font PNGs are taken from the excellent Uzebox Wiki page.

License

Licensed under either of

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.