Crate screen_printer

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Screen Printer

Screen Printer is a Rust crate that will allow you to build and print arrays of data into a grid format.

The purpose of this crate is to make it easier to print rectangular blocks of text to the terminal. Including features like:

  • DynamicPrint, which only prints any characters that changed from any previously printed grid*.
  • PrintingPosition, which allows you to print your string to different places on the terminal, such as the center.

* If the grid changes in size or position it is reprinted in its entirety.

Examples

Using the dynamic print method to print a grid

The core part of this crate is the dynamic_print method for the Printer. This will take a rectangular grid of characters and print only the parts of the grid that have changed since the last print.

use screen_printer::printer::*;

const WIDTH: usize = 3;
const HEIGHT: usize = 3;

fn main() {
  print!("\u{1b}[2J"); // Clear all text on the terminal
  // The default printing position is the bottom left of the terminal
  let mut printer = Printer::new_with_printing_position(PrintingPosition::default());

  // Create the first grid to be printed.
  let grid_1 = "abc\n123\nxyz".to_string();
  // print the first grid.
  printer.dynamic_print(grid_1).unwrap();

  // Wait before printing the second grid.
  std::thread::sleep(std::time::Duration::from_millis(500));

  // Create the second grid to be printed.
  let grid_2 = "abc\n789\nxyz".to_string();
  // Print the second grid.
  // This will only end up printing the difference between the two grids/
  printer.dynamic_print(grid_2).unwrap();
}

This will result in:

abc
123
xyz

Into

abc
789 < only line that was actually printed
xyz
Printing Position

Another feature shown in the above example, the PrintingPosition.

This will print the grid in any of the 9 defined positions on the terminal. These are split by the X and Y axes:

  • Left/Top,
  • Middle, and
  • Right/Bottom.

What is a “rectangular grid”?

A grid is referring to a “grid” of characters, AKA a string with rows and columns. Each row of the “grid” would be sets of characters separated by newlines. Each column would be an individual character between the newlines.

A 3x2 “grid” would be something like: "xxx\nxxx" Each x on either side of the \n is like a column and the \n separates each row.

For a grid to “not be rectangular” would mean that a row has a differing amount of characters from every other, like so: "xx\nxxx"

Modules