Help Activity refresh/Chapter/Turtle Art

From OLPC
< Help Activity refresh‎ | Chapter
Revision as of 15:42, 11 April 2012 by Mokurai (talk | contribs) (→‎Extending Turtle Art: Copied from Sugar Labs Wiki)
Jump to navigation Jump to search

About Turtle Art

File:Activity-Turtle Art.svg

Turtle Art, also known as Turtle Blocks, is an activity with a Logo-inspired graphical "turtle" that draws colorful art based on snap-together visual programming elements. Its "low floor" provides an easy entry point for beginners. It also has "high ceiling" programming, graphics, mathematics, and Computer Science features which will challenge the more adventurous student.

Where to get Turtle Art

http://activities.sugarlabs.org/en-US/sugar/addon/4027

Note: There are two inter-compatible programs: Turtle Art and Turtle Blocks. Turtle Art, which closely parallels the Java version of Turtle Art maintained by Brian Silverman, offers a small subset of the functionality of Turtle Blocks. This is the version included in the Sugar distribution. Sugar users probably want to use Turtle Blocks rather than Turtle Art. (Also see Turtle Confusion, a collection of programming challenges designed by Barry Newell.)

Using Turtle Art

File:Screenshot of "Turtle Art Activity" getting started.png

Start by clicking on (or dragging) blocks from the Turtle palette. Use multiple blocks to create drawings; as the turtle moves under your control, colorful lines are drawn.

You add blocks to your program by clicking on or dragging them from the palette to the main area. You can delete a block by dragging it back onto the palette. Click anywhere on a "stack" of blocks to start executing that stack or by clicking in the Rabbit (fast) , Turtle (slow) or Bug (debug) buttons Rabbitturtle.jpg on the Project Toolbar.

The basics

Drawing shapes

Displaying things

Boxes, Stacks and the Heap

(aka variables, subroutines and the stack)

Mathematics

Keyboard, mouse and sensor input

The Toolbars

<Activity-specific descriptions>

Learning with Turtle Art

Tony Forster and Mokurai have created a number of Turtle Art Tutorials on a wide range of math, programming, art, and Computer Science topics. There is also a substantial literature of educational materials using the Logo programming language, from which Turtle Art and Turtle Blocks derive. The Exploring with Logo series from MIT Press is particularly recommended for showing how far beyond simple graphics Logo can go. Mokurai recommends starting with his first three, specifically designed for helping beginners of all ages, starting with the preliterate in preschool.

Extending Turtle Art

There are versions of Turtle Art in several programming languages and environments, including Logo, Python, Smalltalk, and others. Turtle Art can export programs in Logo, as explained below. There are programmable blocks in Turtle Art which make it possible to include any Python program within the Turtle Art world. The simplest case is a single function call used in a graphing program, but there is no inherent limit on what capabilities of Python one can add to TA.

Turtle Art can export its projects to Berkeley Logo (using either View Source or the Save as Logo button on the Project Toolbar) You can download the Berkeley Logo activity here.

Logo code generated from your project is viewable in the View Source panel in some versions of Turtle Art, but as of v100, the Turtle Art project itself is shown instead.

Note: The Save-as-Logo button saves to the Journal as "logosession.lg". UCB Logo does not yet access the Journal directly, so it is necessary to copy the project out of the Journal using the "copy-from-journal" command in the Terminal Activity and then accessing the project using the File menu within the UCB Logo Activity.

copy-from-journal logosession.lg

Alternatively, you can open the logosession in 'Write', copy the Logo code to the clipboard, and then paste it into the UCB Logo Activity.

Python Blocks in Turtle Art

There are two ways to create Python blocks: by loading sample code provided with Turtle Art or by loading Python code the your Journal.

loading sample code

A number of individual sample programs are provided. Clicking on the Load Python Block button on the Load/Save Toolbar File:Loadpythonsamples.jpg will invoke a file-selector dialog. Select the sample that you want and it will be both copied to the Journal and loaded into a Python block.

File:Pythonsampleselector.jpg

loading code from the Journal

Clicking on a Python block File:Pythoncodeblock.jpg that has been dragged onto the canvas from the Extras palette will invoke an object-selector dialog.

File:Pythonobjectselector.jpg

Select the Python code that that you want and that code will be loaded into the selected block.

You can't run a Python block by clicking on it, as that opens the object selector; instead attach the block to another one and click elsewhere on the stack you have created.

Which ever way you create them, multiple Python blocks can have different code loaded in them.

Modifying Turtle Art

Where to report problems

Credits

Turtle Art