crono

Crono is a 2d video game framework based around SDL2.

NOTE Still under development, but games can be sort of played now

The major part holding this back is animation is super choppy still.

Installation

Include in your shard.yml

dependencies:
  crono:
    github: jwoertink/crono
    branch: master

Be sure to have SDL2 installed!

macOS

brew install sdl2
brew install sdl2_image
brew install sdl2_ttf
brew install sdl2_mixer --with-flac --with-fluid-synth --with-libmikmod --with-libmodplug --with-libvorbis --with-smpeg2

Linux Debian

Usage

"Hello World" example.

require "crono"

class MyGameWindow < Crono::Window
  @main_text : Crono::Font?
  
  def after_init
    font_path = File.join(__DIR__, "assets", "fonts", "lobster.ttf")
    @main_text = Crono::Font.new(font_path, 18)
    @main_text.color = Crono::Color::YELLOW
    @main_text.text = "Hello GameWorld"
  end

  def draw
    brush.draw(@main_text, {100, 75})
  end

end

new_game = MyGameWindow.new(640, 480)
new_game.title = "My Super cool game"

# Call this method to boot the game
new_game.show

Check out some Sample Games

Crono::Window

This is the class that your main class will inherit from. Crono::Window gives you lots of important methods.

initialize - It's still crystal, so you can override this. Just be sure to call initialize(width, height) in it.
after_init - This method is called after SDL has had a chance to set things up.
draw - Define this method to draw to the screen
update - Define this method to update calulcations and such for the next draw to make
key_pressed(key) - This method is called when a key is pressed.
key_down(key) - This method is called when a key is down.
key_up(key) - This method is called when a key is released.

To boot your game, you will instantiate your custom game window class that inherits from Crono::Window.

new_game = MyGameWindow.new(640, 480)

Then give it a title with new_game.title = "Whatever your game is called" Finally you call the show method new_game.show.

Colors

Crono has a few built in colors you can use.

class MyGameWindow < Crono::Window
  def draw
    brush.draw(background_color, {0, 0})
  end

  private def background_color
    Crono::Color.darken(Crono::Color::BLUE, 30)
  end
end