vendor/termion-1.5.1/examples/rainbow.rs

   1 extern crate termion;
   2
   3 use termion::event::Key;
   4 use termion::input::TermRead;
   5 use termion::raw::IntoRawMode;
   6 use std::io::{Write, stdout, stdin};
   7
   8 fn rainbow<W: Write>(stdout: &mut W, blue: u8) {
   9     write!(stdout,
  10            "{}{}",
  11            termion::cursor::Goto(1, 1),
  12            termion::clear::All)
  13             .unwrap();
  14
  15     for red in 0..32 {
  16         let red = red * 8;
  17         for green in 0..64 {
  18             let green = green * 4;
  19             write!(stdout,
  20                    "{} ",
  21                    termion::color::Bg(termion::color::Rgb(red, green, blue)))
  22                     .unwrap();
  23         }
  24         write!(stdout, "\n\r").unwrap();
  25     }
  26
  27     writeln!(stdout, "{}b = {}", termion::style::Reset, blue).unwrap();
  28 }
  29
  30 fn main() {
  31     let stdin = stdin();
  32     let mut stdout = stdout().into_raw_mode().unwrap();
  33
  34     writeln!(stdout,
  35              "{}{}{}Use the up/down arrow keys to change the blue in the rainbow.",
  36              termion::clear::All,
  37              termion::cursor::Goto(1, 1),
  38              termion::cursor::Hide)
  39             .unwrap();
  40
  41     let mut blue = 172u8;
  42
  43     for c in stdin.keys() {
  44         match c.unwrap() {
  45             Key::Up => {
  46                 blue = blue.saturating_add(4);
  47                 rainbow(&mut stdout, blue);
  48             }
  49             Key::Down => {
  50                 blue = blue.saturating_sub(4);
  51                 rainbow(&mut stdout, blue);
  52             }
  53             Key::Char('q') => break,
  54             _ => {}
  55         }
  56         stdout.flush().unwrap();
  57     }
  58
  59     write!(stdout, "{}", termion::cursor::Show).unwrap();
  60 }