kame (Japanese for turtle)
kame is an implementation of the Logo programming language built as a challenge to myself. I wanted a simple way to introduce programming in Ruby to my daughter and thought this would be fun.
With kame, you control the movement of a turtle around a piece of paper by programming commands. With these simple commands your turtle will draw you a picture.
It's a nice introduction to programming for kids and will also help their maths :o)
What it does
You create a Ruby file with commands that instructs a turtle (kame) to move around. You can tell the turtle to move forward or backward, rotate, put his pen down on the paper or pick it up. You can also change the colour of the pen and paper.
The turtle starts in the top left corner of the kame window facing to the right and will move from there depending on your commands.
Each command is on a new line and they are executed in order.
As this is using Ruby, you also have access to Ruby constructs such as loops and functions.
I've tested this on OSX Snow Leopard and also Windows 7. Both work fine :o) It should also work on OSX Lion and Linux in theory, but I haven't tested this yet. Please let me know if you try it.
gem install kame
Create a new text file called square.rb and paste the below code in and save it:
require "kame" Kame.new do forward 100 turn_right 90 forward 100 colour :red pen_down 4.times do turn_right 90 forward 50 end end
You can find more samples in my kame_samples repro. One of which is this little flower <3
In the console use this:
To move the turtle forward by 50 pixels from it's current position, you can use the
To move the turtle backward by 75 pixels from it's current position, you can use the
You can change the colour of the turtle's pen at any time (on the paper or not) with the
To tell the turtle to put his pen down onto the paper use the
pen_down command. There is an optional parameter for the pen colour to switch to, if not supplied the pen is not changed:
pen_down pen_down :red
To tell the turtle to pick his pen up again, use the
You can ask the turtle to rotate 90 degrees to the left (anti-clockwise) on the spot without moving by using the
You can ask the turtle to rotate 90 degrees to the right (clockwise) on the spot without moving by using the
Here is a list of the available colours:
:white :black :red :green :blue :yellow :pink :grey :orange :purple :brown :peach :turquoise :silver :gold :violet
In addition to commanding the turtle, there are some options you can specify. You pass these options to the Kame constructor like so:
Kame.new(:width => 800, :height => 600) do ... end
Here is a list of all options with their default values (all are optional):
:width => 640 # The width of the paper in pixels :height => 480 # The height of the paper in pixels :paper => :white # The colour of the paper (from the list above) :title => 'Kame' # The window title :speed => 10 # The speed that the turtle draws. This is how many lines per second should be drawn :grid => false # Should the help grid be displayed (true | false)? :grid_size => 8 # If the help grid is displayed, this is how many rows and columns should be drawn :grid_colour => :silver # If the help grid is displayed, this is the colour for the grid (from the list above)
Contributing to kame
- Check out the latest master to make sure the feature hasn't been implemented or the bug hasn't been fixed yet
- Check out the issue tracker to make sure someone already hasn't requested it and/or contributed it
- Fork the project
- Start a feature/bugfix branch
- Commit and push until you are happy with your contribution
- Make sure to add tests for it. This is important so I don't break it in a future version unintentionally.
- Please try not to mess with the Rakefile, version, or history. If you want to have your own version, or is otherwise necessary, that is fine, but please isolate to its own commit so I can cherry-pick around it.
Copyright (c) 2011 Andy Pike. See LICENSE.txt for further details.