0.88/Turtle Art

Turtle Art

Introduction

Turtle Art is an activity with a Logo-inspired graphical "turtle" that draws colorful art based on snap-together visual programming elements.

Turtle Art is intended to be a stepping stone to the Logo programming language, but there are many restrictions compared to Logo. (Only numeric global variables and stack items are available, no lists or other data-structures. The conditionals and some of the functions only take constants or variables, not expressions. Limited screen real-estate makes building large programs unfeasible.) However, you can export your Turtle Art creations to Berkley Logo. The sensor-enabled version of Turtle Art also has a facility for sensor input, so, for example, you can move the Turtle based upon sound volume or pitch.

Turtle Art is in the same tradition as Etoys, Scratch, Lego Mindstorms™, and Lego Microworlds™.

Turtle Art is used extensively in Sugar deployments and numerous materials for support in the classroom have been developed. Of course, since Turtle Art is a Logo derivative, many of the classic Logo exercises are well suited for engaging students in Turtle Art. For example, Tony Forster has been blogging about a wide variety of Turtle Art activities. Gonzalo Odiard has written a short introduction to Turtle Art.

More Info:

• Turtle Art Sugar Activity homepage
• Turtle Art gallery (See [1])
• Turtle Art Manual (See [2])
• Turtle Art teacher guides from Uruguay (See [3])
• Turtle Art teacher guides from Peru (See [4])
• Turtle Art student guide (See [5])
• Tony Forster blog on Turtle Art (See [6])
• Bill Kerr blog on Turtle Art (See [7])
• Barry Newell worksheet (See [8])

What is new for users

The most visible change is the incorporation of the new scalable block design.

Minor bugs and feature changes include: 83

• added new user-interface features

o support for multiple turtles
o expandable blocks
o collapsible stacks
o runtime block highlighting
o error highlighting
o trash palette (with restore)
o palette better integrated into Sugar toolbar
o variable-length string blocks
o editable string blocks
o paste text from Sugar clipboard to string blocks
o new prefix boolean logic
o showblock to compliment hideblock
o fullscreen block
o Cartesian and polor coordinate blocks
o color blocks
o editible macros (used for presentation blocks)
o labels on coordinate-grid overlays
o more complete support in non-Sugar environments
o new (and improved) sample code
o Logo code for project added to View Source
o save SVG block lets you generate SVG with Turtle Art
o improved export-to-HTML logic
o new translations

• completed a major refactoring of the code

o 90% smaller download bundle-size
o faster first-time launch
o greatly simplified i18n maintenance
o easier to extend with new blocks and palettes 

82

• minor updates to Spanish translations

81

• fixed keyboard input bug introduced in v79

80

• new Finnish translations

79

• backspace enabled when entering numbers
• arbitrarily long numeric strings enabled
• fixed Python error in sample code
• clean up of en artwork
• fix bug in load_image
• detecting XO 1.5 hardware for font-scaling problem
• keyboard and gamepad navigation
• expanded hover help
• better logic for block selection used by copy/paste

78

• new artwork for pen palette
• color blocks

77

• hide status block on start up
• save reference to Python code loaded from the Journal

76

• fixed import error in project
• fixed bullets in exporthtml
• added proper scaling for coordinate blocks
• moved status layer forward

75

• Cartesian coordinates overlay
• polar coordinates overlay
• coordinate display on View Toolbar
• Option to rescale coordinate system to 100x100 on View Toolbar
• Reordered the palettes (moved misc. down)

74

• load start block for new projects
• fixed bug with reloading descriptions from Journal
• added hover help to command line version
• initiate the import Python chooser when Python block is clicked
• saving pastable code to html export
• fixed some problems in export to HTML code

What is new for developers

Raúl Gutiérrez Segalés and I completed a major refactoring for 0.88 which includes a block factory--a more object-oriented approach that should facilitate a more decentralized development approach.

Compatibility

Compatible with all versions of Sugar although some functionality is lost with pre-0.82 versions and sharing is incompatible with previous versions.

Detailed changes

As of Version 83

Open tickets

• #472 Remove unexpected 'save/load' tab from toolbar
• #489 Turtle Art text entry should use Entry widget
• #673 Logo program should be displayable in the document View Source
• #1057 Turtle Art feature to add support for "pages"
• #1188 Load samples from turtleart.org
• #1203 Rebase Turtle Art graphics on Cairo
• #155 Turtle Art with Sensors has different requirements for non-XO hardware
• #491 Turtle Art sharing needs new logic
• #548 Turtle Art: read and write to text file
• #552 Turtle art: reinstate sensor input

Credits

• Walter Bender and Raúl Gutiérrez Segalés (with help from Simon Schampijer)
• Especially helpful community feedback from Tony Forster, Ed Cherlin, and Bill Kerr
• Brian Silverman is the first author of Turtle Art