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.

Cartesian and polar coordinate grids
Collapsible stack
Collapsed stack
Python function with one, two, or three variables
Expandable bullet list (two bullets)
Expandable bullet list (four bullets)
Enlarged blocks
Shrunken blocks
100 Turtles
SVG output using the save SVG block

Minor bugs and feature changes include: 83

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

completed a major refactoring of the code
- 90% smaller download bundle-size
- faster first-time launch
- greatly simplified i18n maintenance
- 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.

Internationalization (i18n) and Localization (l10n)

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

#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
#491 Turtle Art sharing needs new logic

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

0.88/Turtle Art

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