Struct LcdScreen

pub struct LcdScreen<const R: usize, const C: usize> { /* private fields */ }

A simulated LCD dot-matrix screen.

The screen has R rows and C columns of dots. Note: The number of rows and columns of dots for the screen is specified as a const parameter on the type of the screen, rather than as an argument to the constructor function new.

Parameters

• R - The number of rows of dots of the screen
• C - The number of columns of dots of the screen

Examples

use std::{thread::sleep, time::Duration};

use rand::{thread_rng, Rng};
use sdl2::{event::Event, keyboard::Keycode};
use simulate_lcd::{Bitmap, LcdScreen, LCD_DARK_GREEN, LCD_LIGHT_GREEN};

const NANOS_PER_SEC: u64 = 1_000_000_000;

fn main() {
    let sdl_context = sdl2::init().unwrap();
    let mut screen = LcdScreen::<64, 96>::new(
        &sdl_context,
        "LCD Example: Random",
        LCD_DARK_GREEN,
        LCD_LIGHT_GREEN,
        10,
        10,
     )
     .unwrap();

     let mut event_pump = sdl_context.event_pump().unwrap();
     'running: loop {
        for event in event_pump.poll_iter() {
            match event {
                Event::Quit { .. }
                | Event::KeyDown {
                    keycode: Some(Keycode::Escape),
                    ..
                } => break 'running,
                _ => {}
             }
         }
         let mut rng = thread_rng();

         let random_bits: Vec<[bool; 96]> = (0..64).map(|_| rng.gen()).collect();

         screen.draw_bitmap(&random_bits.try_into().unwrap()).unwrap();

         sleep(Duration::from_nanos(NANOS_PER_SEC / 60));
     }
 }

Implementations

impl<const R: usize, const C: usize> LcdScreen<R, C>

pub fn new( sdl_context: &Sdl, title: &str, on_color: Color, off_color: Color, dot_width: u32, dot_height: u32, ) -> Result<LcdScreen<R, C>, LcdError>

Creates a simulated LCD screen.

Note: The number of rows and columns of dots for a screen is specified as a const parameter on the type of the screen, rather than as an argument to this function.

Arguments

• sdl_context - An Sdl context object
• title - The title of the window containing the screen
• on_color - A Color object representing the color of a dot when it is ‘on’
• off_color - A Color object representing the color of a dot when it is ‘off’
• dot_width - The width of a dot on the screen in pixels
• dot_height - The height of a dot on the screen in pixels

Examples

let mut screen = LcdScreen::<64, 96>::new(
        &sdl_context,
        "LCD Example: Blank",
        LCD_DARK_GREEN,
        LCD_LIGHT_GREEN,
        10,
        10,
     )
     .unwrap();

Errors

• LcdError::Video when there is an error initializing the SDL video subsystem
• LcdError::WindowBuild when there is an error building the window
• LcdError::CanvasBuild when there is an error building the window canvas
• LcdError::WindowWidth when the total window width, in pixels, would exceed i32::MAX
• LcdError::WindowHeight when the total window width, in pixels, would exceed i32::MAX

pub fn draw_bitmap<'a, BM: Into<&'a Bitmap<C, R>>>( &mut self, bm: BM, ) -> Result<(), LcdError>

Draws a bitmap to a simulated LCD screen.

Arguments

• bm - A Bitmap, or something that can be converted into a bitmap, to write to the LCD screen

Examples

let mut screen = LcdScreen::<2, 2>::new(
        &sdl_context,
        "LCD Example: Checkerboard",
        LCD_DARK_GREEN,
        LCD_LIGHT_GREEN,
        100,
        100,
     )
     .unwrap();

screen.draw_bitmap(&[[true, false], [false, true]]);

Errors

• LcdError::Fill when there is an error filling one of the dots with the relevant color