Trait Render

pub trait Render {
    // Required method
    fn brightness_at(&self, x: usize, y: usize) -> u8;
}

A trait providing the information that Display needs to render an image.

Example implementation

Here’s an example of a 5×5 image type, using one byte for each ‘pixel’:

struct GreyscaleImage (
    [[u8; 5]; 5]
);

impl GreyscaleImage {
    const fn new(data: &[[u8; 5]; 5]) -> GreyscaleImage {
        GreyscaleImage(*data)
    }
}

impl Render for GreyscaleImage {
    fn brightness_at(&self, x: usize, y: usize) -> u8 {
        self.0[y][x]
    }
}
const GREY_HEART: GreyscaleImage = GreyscaleImage::new(&[
    [0, 9, 0, 9, 0],
    [9, 5, 9, 5, 9],
    [9, 5, 5, 5, 9],
    [0, 9, 5, 9, 0],
    [0, 0, 9, 0, 0],
]);

Required Methods

fn brightness_at(&self, x: usize, y: usize) -> u8

Returns the brightness value for a single LED.

The ranges for the x and y coordinates are 0..IMAGE_COLS and 0..IMAGE_ROWS, as defined by the Matrix for the Display’s Frame.

(0, 0) is the top left.

The result must be in the range 0..=MAX_BRIGHTNESS

Panics

If the provided coordinates are out of range, may panic or return an arbitrary in-range result.

Implementors