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diff --git a/source/turtleart.markdown b/source/turtleart.markdown deleted file mode 100644 index 7be06c2..0000000 --- a/source/turtleart.markdown +++ /dev/null @@ -1,569 +0,0 @@ -% Turtle Art -% -% - -About -===== - -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 -======================= - -Is included in the OLPC image, and can be downloaded from the [Sugarlabs -Activities -repository](http://activities.sugarlabs.org/en-US/sugar/addon/4027) - -Using Turtle Art -================ - -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  on -the Project Toolbar. - -Toolbars -======== - -Main Toolbar ------------- - -From left to right: - -- Activity toolbar (includes sharing; saving/loading options); -- Edit toolbar (including copy and paste); -- View toolbar (including full-screen, coordinate overlays; turtle - status, etc.); -- Palette toolbar (including all programming blocks); -- erase canvas; -- run project fast (rabbit); -- run project slow (snail); -- stop project; -- save a snapshot (save a copy of the current state of the project); -- load examples; -- display help palette; -- stop activity - -Keyboard short cuts for the above: Alt+ palette; blocks; run; walk; -stop; erase; e.g., Alt+e will erase the screen. Esc will return from -full-screen mode. - -**Notes:** The run buttons are tied to the Start Block. If no Start -Block is used, then all blocks are run when either run button is -clicked. The "rabbit" button runs the blocks at maximum speed. The -"snail" button pauses and displays the turtle and block values between -each step. - -On older versions of Sugar (e.g., 0.84), the main toolbar will look like -this: - -Project Toolbar ---------------- - -From left to right: - -- Project title; -- Write to Journal (on newer versions of Sugar) -- Keep button (not shown; only appears on older Sugar systems) -- Share button; -- Share blocks; shown in disable state. Used to share stacks of blocks - between collaborators. -- Save as image; -- Save as Logo; -- Load a previously saved project from the Sugar Journal; -- Load Python code into a programmable block - -**Notes:** -: - On older Sugar systems, these controls appear on the - Import/Export toolbar. - - - On smaller screens, the load/save buttons are shown on a - palette. - - To share a stack, click on the share button. The cursor will - change to the hand shape Ta-hand-cursor.png. Place the cursor on - any block or stack of blocks and click. The blocks will be - shared and the cursor will change back to the arrow shape. - -Edit Toolbar ------------- - -The Edit toolbar is used to copy stacks of blocks to the clipboard and -to paste stacks from the clipboard. To copy a stack, click on the copy -button or type Ctrl-c. The cursor will change to the hand shape -Ta-hand-cursor.png. Place the cursor on any block or stack of blocks and -click. The blocks will be copied to the Sugar clipboard and the cursor -will change back to the arrow shape. To paste from the clipboard, type -Ctrl-v or click the paste button. - -From left to right: - -- Copy -- Paste - -View Toolbar ------------- - -From left to right: - -- Full-screen button; -- Cartesian-coordinate grid; -- polar-coordinate grid; -- not shown: centimeter-coordinate grid (XO-only); -- display of x,y coordinates, heading of turtle; -- Rescale-coordinates button; -- Grow block size; -- Shrink block size -- Disable/enable hover help - -Palettes Toolbar ----------------- - -The palette menus are revealed by clicking on the Block icon on the main -toolbar. (On older Sugar systems, select the Projects toolbar. When -running Turtle Art from GNOME, the palettes are visible by default.) - -There are ten palettes of program elements available for program -construction: Turtle movements; Pen attributes; Color attributes; -Numeric operators; Logical operators; Logical blocks; Sensor blocks; -Media blocks; Customization functions; and Presentation blocks. An -eleventh palette is used for restoring blocks from the trash. - -**Note:** Additional palettes may be loaded by plugin extensions to -Turtle Blocks. - -Blocks are dragged from the palette onto the canvas surface. To dispose -of a block, drag it back onto the palette. (It will be placed onto the -trash palette.) - -The  button, which -replaces the Stop button on the main toolbar while the program is -executing, is used to reveal the program blocks. Individual palettes can -be hidden by clicking on their highlighted tab. - -Turtle Palette --------------- - -These blocks are used to control the movements of the turtle. - -- forward: move turtle forward -- back: move turtle backward -- clean: clear the screen and position the turtle in the center of the - screen, pen down, color red, heading 0 -- left: rotate turtle counterclockwise -- right: rotate turtle clockwise -- arc: move turtle along an arc -- set xy: set turtle x,y position (0,0) is the center of the screen -- seth: set turtle heading -- xcor: holds current x-coordinate value of the turtle (can be used in - place of a number block) -- ycor: holds current y-coordinate value of the turtle (can be used in - place of a number block) -- heading: holds current heading value of the turtle (can be used in - place of a number block) - -Pen Palette ------------ - -These blocks are used to control the attributes of the turtle's pen. - -- pen up: turtle will not draw when moved -- pen down: turtle will draw when moved -- set pen size: sets the width of the line drawn by the turtle -- fill screen: fill the screen with a color/shade and reposition the - turtle in the center of the screen -- pen size: width of the line drawn by the turtle (can be used in - place of a number block) -- set color: sets the pen color -- set shade: sets the pen shade -- set gray: sets the gray-level of the pen (Only available in Turtle - Blocks) -- color: current pen color (can be used in place of a number block) -- shade: current pen shade (can be used in place of a number block) -- gray: current pen gray level (can be used in place of a number - block) (Only available in Turtle Blocks) -- start fill: starts a filled polygon (straight sides, not arcs) -- end fill: ends a fill polygon (straight sides, not arcs) - -Color Palette -------------- - -These blocks can be used with the set-pen-color block in place of a -number block. - -Numbers Palette ---------------- - -These blocks are arithmetic and boolean operators. - -- addition: adds two numeric inputs (also can be used to concatenate - strings) -- subtraction: subtracts the bottom numeric input from the top input -- multiplication: multiplies two numeric inputs -- division: divided top input (numerator) by bottom input - (denominator) -- identity: identity function (used for spacing blocks) -- modulo (remainder): calculates remainder when dividing top input by - the bottom input -- square root (Only available with Turtle Blocks) -- random number: generates a random integer between the minimum and - maximum values -- number block: a numeric input -- greater than: boolean greater than operator (used with flow blocks) -- less than: boolean less than operator (used with flow blocks) -- equal to: boolean equal to operator (used with flow blocks) -- not: boolean not (Only available with Turtle Blocks) -- and: boolean and (Only available with Turtle Blocks) -- or: boolean or (Only available with Turtle Blocks) - -Flow Palette ------------- - -These blocks control program flow. - -- wait: pause program execution (unit is seconds) -- forever: continuously repeat execute stack under the right flow -- repeat: repeat the execution of stack under the right flow a - specified number of times -- if/then: conditional execution of the stack under the right flow - (uses boolean operators found on the Number palette) -- if/then/else: conditional execution of the stack under the center - and right flows (uses boolean operators found on the Number palette) -- vertical spacer -- stop stack: interrupt execution -- while: execute stack under right flow while the condition is true - (uses boolean operators found on the Number palette) (Only available - with Turtle Blocks) -- until: execute stack under right flow until the condition is true - (uses boolean operators found on the Number palette) (Only available - with Turtle Blocks) - -**Note:** Nesting while and/or until blocks is not always reliable. If -you encounter an error, try putting the nested block in a separate -stack, accessed with an action block. - -Blocks Palette --------------- - -These blocks are for defining variables and subroutines. - -- start: connects action to toolbar 'Run' button -- store in box 1: store a number, string, or media object in box 1 - (Only available with Turtle Blocks) -- store in box 2: store a number, string, or media object in box 2 - (Only available with Turtle Blocks) -- text: string input -- box 1: current value of box 1 (can be used in place of a number - block) (Only available with Turtle Blocks) -- box 2: current value of box 2 (can be used in place of a number - block) (Only available with Turtle Blocks) -- box: current value of named box (can be used in place of a number - block) -- store in: store a number, string, or media object in a named box -- action: top of named action stack -- action 1: top of action 1 stack (Only available with Turtle Blocks) -- action 2: top of action 2 stack (Only available with Turtle Blocks) -- action: execute named action stack -- action 2: execute action 2 stack (Only available with Turtle Blocks) -- action 1: execute action 1 stack (Only available with Turtle Blocks) - -**Note:** When a named action or named box block are used, new blocks -appear on the palette that correspond to these names; e.g., if a top of -action stack is rename, "to square", an action block, "to square" is -added to the palette. - -Sensors Palette ---------------- - -- query keyboard: check for keyboard input (results are stored in the - keyboard block) -- keyboard: current value of keyboard input (can be used in place of a - number block) -- read pixel: push the RGB value of the pixel under the turtle onto - the FILO (blue is first, red is last) -- turtle sees: the "palette color" of the pixel under the turtle -- time: number of seconds since program began -- sound: raw data from microphone ranging -32000 to 32000 -- volume (loudness): ranging 0 to 32000 -- pitch: the resolution is +-8Hz -- brightness: average luminance seen through camera -- camera: grab image from camera -- button down: current state of the mouse button (1 == down; 0 == ip) -- mouse x: x position of mouse -- mouse y: y position of mouse - -The OLPC XO can measure external inputs with its microphone jack: - -- resistance: measurement range is 750 to 14k ohms, (OLPC XO1) and 2k - ohms to open circuit (OLPC XO1.5) -- voltage: measurement range is DC 0.4V to 1.85V. (OLPC XO1) and 0.17V - to 3.0V (OLPC XO1.5) - -The OLPC XO 1.75 also includes an accelerometer. - -- accelerate (not shown): measure the acceleration of the computer. - Results are pushed to the stack and can be retrieved by using 3 - 'pop' blocks (one for X (horizontal), one for Y (vertical), and one - for Z (forward/backward)) - -See [Using Turtle Art -Sensors](http://wiki.sugarlabs.org/go/Activities/Turtle_Art/Using_Turtle_Art_Sensors) -for more details about the sensor blocks. - -Media Palette -------------- - -These are a collection of blocks used for displaying media objects, such -as images from the Journal. - -- journal: Sugar Journal media object (used with show block) (also - available in Turtle Art) -- audio: Sugar Journal media object (used with show block) -- video: Sugar Journal media object (used with show block) -- description: Sugar Journal description field (used with show block) -- text: text string (used with show block; also used with box and - action blocks) -- show: draw text or display media object from the Journal -- set scale: sets the scale of images displayed with show block -- save picture: save the canvas to the Sugar Journal as a .png image - (note: saves the canvas as displayed) -- save SVG: save turtle graphics to the Sugar Journal as a .svg image - (note: only saves the changes to the canvas in the current execution - run) -- scale: sets scale for show block (100% is full-screen) -- wait for media: used to pause program while audio or video file - plays -- media stop: stop current sound or video -- media pause: pause current sound or video -- media resume: resume playing paused media -- speak: sends text to the voice synthesizer -- sine wave: plays a sine wave of a given frequency, amplitude, and - duration - -Extras Palette --------------- - -These are a collection of extra blocks for accessing advanced features -only available in Turtle Blocks. - -- push: push value onto FILO (first-in last-out) heap -- show heap: show FILO in status block -- empty heap: empty the FILO -- pop: pop value off of the FILO (can be used in place of a number - block) -- print: print value in status block (also available in Turtle Art) -- comment: program comment (displayed in "walk" mode) -- chr: Python chr primitive: converts ASCII to character (useful for - converting keyboard input to text) -- int: Python int primitive: converts input to integers -- Python: a programmable block (can be used in place of a number - block) - - > add your own math equation in the block, e.g., sin(x); This block - > is expandable to support up to three variables, e.g. f(x,y,z) - -- Import Python: import Python code from the Sugar Journal (a more - general-purpose programmable block). This block accepts a single - variable x, as an input or up to 3 variables as an array x[0], x[1] - and x[2] -- Cartesian: display Cartesian coordinate grid overlay -- polar: display polar coordinate grid overlay -- turtle: specify which turtle is active -- turtle shell: import a image from the Journal to use as the turtle's - 'shell', i.e., replace the turtle with a sprite. -- sandwich clamp: "clamp" a stack of blocks to hide - -Portfolio Palette ------------------ - -These blocks are used to make multimedia presentations only available in -Turtle Blocks. - -- hide blocks: hides all blocks and palettes (useful for decluttering - the screen during presentations) (also available in Turtle Art) -- show blocks: shows blocks and palettes (useful for resuming - programming after a presentation) -- full screen: goes into full-screen mode (hides Sugar toolbars) -- list slide: used for bulleted lists; This block is expandable, - allowing you to add as many bullets as you need -- picture slides: used for picture slides (1×1, 2×2, 1×2, and 2×1) - -Only available in Turtle Blocks: - -- left: holds current x-coordinate value of the left edge of the - screen (can be used in place of a number block) -- top: holds current y-coordinate value of the top edge of the screen - (can be used in place of a number block) -- right: holds current x-coordinate value of the right edge of the - screen (can be used in place of a number block) -- bottom: holds current y-coordinate value of the bottom edge of the - screen (can be used in place of a number block) -- width: screen width (can be used in place of a number block) -- height: screen height (can be used in place of a number block) - -**Note:** The slide blocks expand into stacks that can be edited for -customized presentations. - -Trash Palette -------------- - -This palette holds any blocks that have been put in the trash. You can -drag blocks out of the trash to restore them. The trash palette is -emptied when you quit Turtle Art. - -Vertical palettes ------------------ - -Learning with Turtle Art -======================== - -Tony Forster and Mokurai have created a number of Activities/Turtle -Art/Tutorials 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. - -- [You be the - Turtle](http://wiki.sugarlabs.org/go/Activities/Turtle_Art/Tutorials/You_be_the_Turtle) - without the computer. -- [Mathematics and - art](http://wiki.sugarlabs.org/go/Activities/Turtle_Art/Tutorials/Mathematics_and_art), - an introduction to TA. -- [Counting](http://wiki.sugarlabs.org/go/Activities/Turtle_Art/Tutorials/Counting) - -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. - -Exporting to Berkeley Logo -========================== - -Turtle Art can export its projects to [Berkeley -Logo](http://www.cs.berkeley.edu/~bh/) (using either **View Source** or -the **Save as Logo** button on the **Project Toolbar**) - -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 - 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. - -**Loading code from the Journal** - -Clicking on a Python block - that has been -dragged onto the canvas from the Extras palette will invoke an -object-selector dialog. - -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 -==================== - -Turtle Art is under the MIT license. You are free to use it and learn -with it. You are also encourage to modify it to suit your needs or just -for a further opportunity to learn. - -Much of the motivation behind the Version 83 refactoring of the code was -to make it easier for you to make changes. Most changes can be confined -to two modules: taconstants.py and talogo.py. The former defines the -blocks and palettes; the latter defines what code is executed by a -block. - -**Note:** As of Version 106, there is also support for plugins. If you -can use the plugin mechanism to add support for additional devices, -e.g., Arduino, or for making modifications such as are described below -without making changes to the standard code base. (The advantage to the -latter is that your changes will remain intact even after you upgrade to -a newer version.) - -The tabasics.py file contains the constants that by-in-large determine -the behavior of Turtle Art. Notably, the block palettes are defined -below. If you want to add a new block to Turtle Art, you could simply -add a block of code to that file or to turtle\_block\_plugin.py, which -contains additional blocks. (Even better, write your own plugin!!) - -Adding a new palette is simply a matter of: - - palette = make_palette('mypalette', # the name of your palette - colors=["#00FF00", "#00A000"], - help_string=_('Palette of my custom commands')) - -For example, if we want to add a new turtle command, 'uturn', we'd use -the add\_block method in the Palette class. - - palette.add_block('uturn', # the name of your block - style='basic-style', # the block style - label=_('u turn'), # the label for the block - prim_name='uturn', # code reference (see below) - help_string=_('turns the turtle 180 degrees')) - -Next, you need to define what your block will do. def\_prim takes 3 -arguments: the primitive name, the number of arguments—0 in this -case—and the function to call—in this case, the canvas.seth function to -set the heading. - - self.tw.lc.def_prim('uturn', 0, - lambda self: self.tw.canvas.seth(self.tw.canvas.heading + 180)) - -That's it. When you next run Turtle Art, you will have a 'uturn' block -on the 'mypalette' palette. - -You will have to create icons for the palette-selector buttons. These -are kept in the icons subdirectory. You need two icons: mypaletteoff.svg -and mypaletteon.svg, where 'mypalette' is the same string as the entry -you used in instantiating the Palette class. Note that the icons should -be the same size (55x55) as the others. (This is the default icon size -for Sugar toolbars.) - -Where to report problems -======================== - -Please file bug reports -[here](https://bugs.sugarlabs.org/newticket?component=Turtleart). - -Credits -======= - -> Walter Bender and Raúl Gutiérrez Segalés maintain the code (with some -> occasional help from Simon Schampijer) Alan Jhonn Aguiar Schwyn and -> the Butia Team have provided great feedback and many patches. -> Especially helpful feedback from Tony Forster, Guzmán Trinidad, and -> Bill Kerr Brian Silverman is the first author of Turtle Art |