Eng:Blocks (1.4)

Blocks are puzzle-piece shapes that are used to create code in Scratch. The blocks connect to each other like a jigsaw puzzle, where each data type (event, command, reported value, reported boolean, or script end) has its own shape and a specially shaped slot for it to be inserted into this prevents syntax errors. Series of connected blocks are called scripts.

There are ten categories of blocks: Control, Motion, Looks, Sound, Pen, Sensing, Operators, Variables, List and Motor (although there are some other categories and blocks in some Scratch modifications). Only eight are shown at the top.

In total, there are four hat blocks, six C blocks, twenty-six reporter blocks, thirteen Boolean blocks, two cap blocks and seventy-five stack blocks.

Block Shapes
There are six different block shapes: Hat, Stack, Boolean, Reporter, C and Cap.

Hat blocks
Hat blocks are the blocks that start every script. They are shaped with a rounded top and a bump at the bottom this is so you can only place blocks below them. There are four Hat blocks, and they can be found in the Control category.

Stack blocks
Stack blocks are the blocks that perform the main commands. They are shaped with a notch at the top and a bump on the bottom this is so blocks can be placed above and below them. There are 75 Stack blocks the most common block shape.

Boolean blocks
Boolean blocks are the conditions they are either true or false. It is like asking your friend: "Does 2 + 2 = 4?", and they would either tell you "Yes" or "No". With a hexagonal shape, there are 13 of these blocks.

Reporter blocks
Reporter blocks are the values. Reporter blocks can hold numbers and strings. It is like asking a friend, for example, "What is 2 + 2?", and they would answer "4". It isn't just equations however, it can report a variable, for example, "What is your age?". They may answer: "15". Shaped with rounded edges, there are 26 of these blocks not counting the theoretically infinite amount of Reporter blocks that can be made for each variable and list.

C blocks
C blocks are blocks that are made up of "C's". Also known as "Wrap blocks", these blocks loop the blocks within the Cs or check if a condition is true. There are six C blocks, and they can be found in the Control category. C blocks can be bumped at the bottom, or capped.

Cap blocks
Cap blocks are the blocks that stop scripts. They are shaped with a notch at the top and a flat bottom this is so you cannot place any blocks below them. There are two Cap blocks, and they can both be found in the Control category.

List of Blocks
There are 128 blocks in Scratch 1.4.

Control blocks
Control blocks are the blocks that control scripts. There are 16 Control blocks in Scratch 1.4.

Scratch 1.4 has the following four Control Hat blocks:


 * When Green Flag Clicked When the flag is clicked, the script activates.
 * When Key Pressed  When the specified key is pressed, the script activates.
 * When Clicked  When the sprite is clicked, the script activates.
 * When I Receive  When the broadcast is received, the script activates.

Scratch 1.4 has the following four Control Stack blocks:


 * Wait Secs  Pauses the script for the amount of time.
 * Broadcast  Sends a broadcast throughout the Scratch program, activating When I Receive  blocks that are set to that broadcast.
 * Broadcast and Wait  Like the Broadcast  block, but pauses the script until all scripts activated by the broadcast are completed.
 * Wait Until  Pauses the script until the condition is true.

Scratch 1.4 has the following six Control C blocks:


 * Forever A loop that will never end.
 * Repeat  A loop that repeats the specified amount of times.
 * Forever If  A loop that will always check the condition, like putting an If  block inside a Forever block.
 * If  Checks the condition so that if the condition is true, the blocks inside it will activate.
 * If, Else Checks the condition so that if the condition is true, the blocks inside the first C will activate and if the condition is false, the blocks inside the second C will activate.
 * Repeat Until  A loop that will stop once the condition is true.

Scratch 1.4 has the following two Control Cap blocks:


 * Stop Script Stops the script.
 * Stop All Stops all scripts throughout the Scratch program.

Trigger blocks
In the Experimental Viewer, all of the Hat Blocks and Broadcast blocks are in this section.

Motion blocks
Motion blocks are the blocks that control a sprite's movement. There are 16 Motion blocks in Scratch 1.4.

Scratch 1.4 has the following thirteen Motion Stack blocks:


 * Move Steps  Moves the sprite forward the amount of steps.
 * Turn Degrees (Clockwise)  Turns the sprite (clockwise) the specified amount.
 * Turn Degrees (Counter-clockwise)  Turns the sprite (counter-clockwise) the specified amount.
 * Point in Direction  Points the sprite in the direction.
 * Point Towards  Points the sprite towards the mouse-pointer or another sprite.
 * Go to X: Y:   Moves the sprite to the specified X and Y position.
 * Go to  Moves the sprite to the mouse-pointer or another sprite.
 * Glide Secs to X:  Y:   Glides the sprite to the location, taking as long as the specified amount of time.
 * Change X by  Changes the sprite's X position by the amount.
 * Set X to  Sets the sprite's X position to the amount.
 * Change Y by  Changes the sprite's Y position by the amount.
 * Set Y to  Sets the sprite's Y position to the amount.
 * If on Edge, Bounce If touching the edge of the screen, the sprite's direction flips over.

Scratch 1.4 has the following three Motion Reporter blocks:


 * X Position The X position of the sprite.
 * Y Position The Y position of the sprite.
 * Direction The direction of the sprite.

Motor blocks
Motor blocks are extra Motion blocks that are used with the LEGO Education WeDo Robotics Kit. There are five of these blocks, and they are only available in Scratch 1.4.

Scratch 1.4 has the following five Motor Stack blocks:


 * Motor On for Secs  Turns the motor on for the specified amount of time.
 * Motor On Turns the motor on.
 * Motor Off Turns the motor off.
 * Motor Power  Sets the motor's power to the amount.
 * Motor Direction  Sets the motor's direction to the amount.

Looks blocks
Looks blocks are the blocks that control a sprite's look. There are 20 Looks blocks in Scratch 1.4. Three of the 17 sprite Looks blocks have their stage analog.

Scratch 1.4 has the following seventeen Looks Stack blocks:


 * Switch to Costume /Switch to Background  Changes the sprite's/Stage's costume/background to the specified one.
 * Next Costume/Next Background Changes the sprite's/Stage's costume/background to the next one in the costume list.
 * Say for  Secs  A speech bubble appears over the sprite and stays for the specified amount of time.
 * Say  A speech bubble appears over the sprite and will not go away over time. It can be removed using say, and defining no value.
 * Think for  Secs  A thought bubble appears over the sprite and stays for the specified amount of time.
 * Think  A thought bubble appears over the sprite and will not go away over time.
 * Change Effect by   Changes the specified effect by the amount.
 * Set Effect to   Sets the specified effect to the amount.
 * Clear Graphic Effects Clears all graphic effects on the sprite.
 * Change Size by  Changes the sprite's size by the amount.
 * Set Size to % Sets the sprite's size to the amount.
 * Show Shows the sprite.
 * Hide Hides the sprite.
 * Go to Front Puts a sprite in the front.
 * Go Back Layers  Changes the sprite's layer value by the amount.

Scratch 1.4 has the following three Looks Reporter blocks:


 * Costume # (for sprites) / Background # (for the Stage) The number of the sprite/Stage's current costume/background in the list.
 * Size The sprite's size.

Sound blocks
Sound blocks are the blocks that control sound and MIDI functions. There are 13 Sound blocks in Scratch 1.4.

Scratch 1.4 has the following eleven Sound Stack blocks:


 * Play Sound  Plays a sound without pausing the script.
 * Play Sound Until Done  Plays a sound and pauses the script until it finishes.
 * Stop All Sounds Stops all playing sounds.
 * Play Drum for  Beats  Plays the specified drum for the amount of beats.
 * Rest for Beats  Pauses the script for the amount of time.
 * Play Note for  Beats  Plays the note for the amount of beats.
 * Set Instrument to  Sets the instrument to the specified one.
 * Change Volume by  Changes the volume by the amount.
 * Set Volume to %  Sets the volume to the amount.
 * Change Tempo by  Changes the tempo by the amount.
 * Set Tempo to bpm  Sets the tempo to the amount.

Scratch 1.4 has the following two Sound Reporter blocks:


 * Volume The volume.
 * Tempo The tempo.

Pen blocks
Pen blocks are the blocks that control the pen. There are 11 Pen blocks in Scratch 1.4. Scratch 2.0 will probably have 12 or 16 of these blocks.

Scratch 1.4 has the following eleven Pen Stack blocks:


 * Clear Removes all pen marks put on the screen.
 * Pen Down Puts the sprite's pen down.
 * Pen Up Puts the sprite's pen up.
 * Set Pen Color to (color-picker)  Sets the pen color to the specified color shown on the picture.
 * Change Pen Color by  Changes the pen color by the amount.
 * Set Pen Color to (number)  Sets the pen color to the amount.
 * Change Pen Shade by  Changes the pen shade by the amount.
 * Set Pen Shade to  Sets the pen shade to the amount.
 * Change Pen Size by  Changes the pen size by the amount.
 * Set Pen Size to  Sets the pen size to the amount.
 * Stamp Pens the sprite's image on the screen. Can be removed using clear.

Scratch Day pre-alpha of Scratch 2.0 has following one new Pen Stack block:


 * Stamp Transparent Pens the sprite's image on the screen at the transparency of the amount in the block. Can be removed using clear.

Sensing blocks
Sensing blocks are the blocks that detect things. There are 17 Sensing blocks in Scratch 1.4.

Scratch 1.4 has the following two Sensing Stack blocks:


 * Ask and Wait  An input box appears  you type the value in and it stores the value in the answer variable.
 * Reset Timer Resets the timer.

Scratch 1.4 has the following seven Sensing Boolean blocks:


 * Touching ? The condition for checking if the sprite is touching the mouse-pointer or another sprite.
 * Touching Color ? The condition for checking if the sprite is touching a specific color.
 * Color is Touching ?  The condition for checking if a color on the sprite is touching a specific color.
 * Mouse Down? The condition for checking if the mouse is down.
 * Key Pressed?  The condition for checking if the specified key is being pressed.
 * Loud? The condition for checking if the microphone input is loud.
 * Sensor  The condition for checking various input on a Sensor Board.

Scratch 1.4 has the following eight Sensing Reporter blocks:


 * Answer The most recent input with the Ask  And Wait block.
 * Mouse X The mouse-pointer's X position.
 * Mouse Y The  mouse-pointer's Y position.
 * Distance to  The distance from the sprite to the mouse-pointer or another sprite.
 * Timer How much time has passed since the Scratch program was opened or the timer reset.
 * of  The X position, Y position, direction, costume, size or volume of the Stage or a sprite.
 * Loudness How loud the noise is that the microphone is sensing.
 * Sensor Value Various values for things with a Sensor Board  and other Scratch programs' variables with Mesh.

Operators blocks
Operators blocks are the blocks that perform math functions and string handling. There are 17 Operators blocks in Scratch 1.4.

Scratch 1.4 has the following six Operators Boolean blocks:


 * <  The condition for checking if a value is less than the other.
 * =  The condition for checking if two values are equal.
 * >  The condition for checking if a value is greater than the other.
 * and  Joins two conditions.
 * or  Joins two conditions, but they function separately.
 * Not  Makes the condition checked if it is false, not true.

Scratch 1.4 has the following eleven Operators Reporter blocks:


 * +  The value of the addition.
 * The value of the subtraction.
 * *  The value of the multiplication.
 * /  The value of the division.
 * Pick Random to   Picks a random number between the two limits.
 * Join  The two values put right next to each other.
 * Letter of   The specified character of the value.
 * Length of  The length of the value.
 * Mod  The remainder of the division.
 * Round  Rounds the value to the nearest whole number.
 * of  The absolute value (abs), square root (sqrt), sine (sin), cosine (cos), tangent (tan), asine (asin), acosine (acos), atangent (atan), natural logarithm (ln), logarithm (log), exponential function (e^), or base 10 exponential function (10^) of a specified value.

Right clicking some of the blocks will yield more choices of its type.

Variables blocks
Variables blocks are the blocks that hold values and strings. There are 5 Variables blocks in Scratch 1.4.

Scratch 1.4 has the following four Variables Stack blocks:


 * Set to   Sets the specified variable to the amount.
 * Change by   Changes the specified variable by the amount.
 * Show Variable  Shows the variable's Stage Monitor.
 * Hide Variable  Hides the variable's Stage Monitor.

Scratch 1.4 has the following Variables Reporter block:


 * The variable's value.

List Blocks
List blocks are the blocks that manage lists. They are stored in the Variables category. There are eight List blocks in Scratch 1.4.

Scratch 1.4 has the following four List Stack blocks:


 * Add to   Adds an item to the list (the item goes at the bottom of the list of items) with the specified content in it.
 * Delete of   Deletes the item of the list.
 * Insert at  of   Adds an item to the list (the item goes where you specify in the list of items) with the specified content in it.
 * Replace Item of  With   Replaces the item's content with the specified content.

Scratch 1.4 has the following 3 List Reporter blocks:


 * The list's value.
 * Item of   The item's value.
 * Length of  How many items there are in the specified list.

Scratch 1.4 has the following List Boolean block:


 * Contains  The condition for checking if an item's content is the specified text.

Scratch Block Plugin
The Scratch Block Plugin allows blocks and scripts to be used in the Scratch Forums and Scratch Wiki, as well as other sites with the included Javascript. They look like this: when flag clicked go to x: (0) y: (0) // center the sprite for the first stamp stamp forever go to x: (pick random (-240) to (240)) y: (0) stamp wait (0.2) secs change [color v] effect by (pick random (5) to (14)) These blocks were put in place on 27 January 2012 by JSO, a Community Moderator on the Scratch Forums. They were made to replace the "ancient" forum blocks, which have not been updated since the release of Scratch 1.2.