Crysterm is a console/terminal toolkit for Crystal, inspired by Blessed, Blessed-contrib, and Qt.

Advanced features:

Image-rendering backends:

Image::Tek (Tektronix 4014):

Tech intro

Crysterm is supported by the event model in event_handler, color routines in term_colors, terminal handling in tput.cr, GPM mouse in gpm.cr, a terminfo library in unibilium.cr, and an animated PNG/GIF parser in pnggif.

tput.cr implements all the terminal routines, and does not use ncurses. For terminfo bindings it uses unibilium, but it also supports a built-in, standard mode which does not use terminfo at all. (A lot of modern software just hardcodes the sequences.) The other important module at Crysterm's core is event_handler. through which all app events and input are routed.

In-depth introductory doc is in USAGE.md.

Hello world

require "crysterm"

alias C = Crysterm

# A `Window` is the surface your widgets live on.
window = C::Window.new title: "hello"

C::Widget::Box.new \
  parent: window,
  top: "center", left: "center", width: 20, height: 5,
  content: "{center}'Hello {bold}world{/bold}!'\nPress q to quit.{/center}",
  style: C::Style.new(fg: "yellow", bg: "blue", border: true)

# `q` / Ctrl-Q quit by default. Run the main loop:
window.exec

Examples

git clone https://github.com/crystallabs/crysterm
cd crysterm
shards

crystal examples/hello.cr          # the program above
crystal examples/hello2.cr         # the Qt shape: MainWindow + a layout
crystal tests/misc/qt_widgets.cr   # tour of the Qt-inspired widget set
crystal tests/misc/widgets.cr      # tour of the general widget set

Larger, complete applications:

crystal examples/mutt/mutt.cr               # a Mutt-style mail client
crystal examples/pine/pine.cr               # a Pine/Alpine-style mail client
crystal examples/terminal/tid/tid.cr        # a terminal multiplexer
crystal examples/games/minesweeper/minesweeper.cr
crystal examples/games/pong/pong.cr
crystal examples/games/commando/commando.cr
crystal examples/games/wumpus/wumpus.cr

(And many more under examples/ and tests/.)

Testing

Run crystal spec as usual.

Documentation

Run crystal docs as usual.

Thanks

• All the fine folks in the Crystal community.