To declare variables and set certain values ​​for them, the “Variable Initialization” block is used.

For mathematical expressions — "Expression" block.

Also, mathematical expressions, including those that change the values ​​of variables, can be used almost everywhere where you can specify a value.

Blocks and their properties that do not allow the use of mathematical expressions are described in the section "Common blocks".

All variables in the program are global, i.e. their values ​​can be used in any block in the program.

TRIK Studio language

The language used inside the blocks is based on Lua 5.3 and largely follows its syntax. Nevertheless, there are significant differences, so a full description of the language used in TRIK Studio is given here.

• Types

• Tokens

• Operators

• Sensor variables

• Constants

• Built-in functions

Examples of expressions

Declaration of several variables in one block "Expression":

The same using "Variables Initialization" blocks:

Proportional controller for driving along the line using two light sensors for the TRIK platform:

An example of using arrays to set the ports of the “Motors forward” block. An array is created with the name a, the port M3 is assigned to the zero element, the first is M1, then the contents of the first element of the array are changed to M4, then the resulting array is transferred to the “Ports” property of the “Motors forward” block:

Links between blocks in TRIK Studio indicate the control flow of interpretation between blocks.

Example

Let it be necessary that after the delay the program ends immediately. To do this, connect the Timer and End blocks with a link pointing from the "Timer" block to the program end block.

Create links

Links can be created in two ways:

1. Using mouse gesture.

2. Using linkers.

Using mouse gestures

Hover over a block, hold down the right mouse button and draw a line to the second block. The line shape can be arbitrary. It is important that it starts strictly on one block and ends on the second.

If you move the mouse cursor over the link, gray markers are displayed at its ends. By pulling on one of these markers, you can control the link. To attach one of the ends of the connection to the block, you need to pull the corresponding gray marker and release it on the block of interest.

Using linkers

If you drop this relationship on an existing element, these elements will be connected.

If you release the left mouse button when the cursor is on an empty section of the diagram, a menu with the following items will appear:

• Delete

• Create new element

When you select the "Delete" menu item, the created link will be deleted.

When you hover over the menu item "Create a new element" a new menu appears, listing all the possible elements to create. When you select one of these items on the diagram, the corresponding element will be created and join the current link.

Delete links

Links are removed in the same way as blocks.

Add a new block on the link

If you need to add a new block between two linked blocks, drag a block from the Palette panel to the link. Release the mouse button when you hover over a link (not a block).

Create breakpoints

Links in TRIK Studio can be broken lines. To add a breakpoint, move the mouse cursor over the link, click the left mouse button and drag the gray marker that appears.

If the breakpoint of the connection is positioned so that it and the two nearest to it will be located approximately on one straight line, this will lead to the destruction of this breakpoint and smoothing of the broken line in this place.

An array is one of that stores a set of values ​​(array elements) identified by an index. The numbering of indices in the array starts at 0.

Arrays can be created explicitly using the following expressions (the next lines are equivalent):

Or with explicit indices:

You can use arrays without creating them. For example, like this:

In this case, "empty spaces" in the array (indices that did not have an explicit assignment) will be filled with default values:

• 0 — for real and integer;

• false — for boolean;

• empty lines for arrays of strings.

Array values ​​can also be used without curly braces if used as the return value. For example, this expression will return an array of numbers 1 and 2:

This is implemented in order to interpret the enumerations of values ​​(for example, the ports of motors in the block ) as arrays. Therefore, wherever you use a comma-separated value notation, you can use an array.

1. .

2. .

3. .

4. .

5. .

Binary operators

Unary operators

Assignment operator

It has the following form:

variable1, variable2, …, variableN = expression1, expression2, …, expressionN

In its simplest form variable = expression.

Return operator

It is written as an expression and should be at the end of the statement block.

Empty operator

Written as ;.

Example

A statement block with two assignment operators and a return operator:

Besides , in TRIK Studio reserved variables are available that store the values ​​of the readings of sensors connected to the corresponding ports.

These values ​​can be assigned to variables and used in mathematical expressions.

Variables have the form

For example, sensorA1 for TRIK or sensor1 for Lego NXT.

A complete list of sensor variables is provided in sections for specific platforms:

• .

• .

• .

The language uses spaces, tabs, and line breaks outside of string literals only as separators between tokens — they do not affect the interpretation of expressions.

The language has the following keywords:

• and

• false

• nil

• not

• or

• true​

And the following operators:

+ - * / % ^ # & ~ | << >> // == ~= <= >= < > = ( ) { } [ ] ; : , . .. && ||

String literals are written in either single or double-quotes. For example,

a = 'alo123'
a = "alo123"

Integers are written either in decimal, octal, or hexadecimal. Hexadecimal numbers begin with the prefix 0x, octal numbers begin with the prefix 0. For example,

• 3, 345 — decimal number

• 0xff, 0xBEBADA — hexadecimal number

• 07654321 — octal number

Real numbers are written either in conventional or exponential form. For example,

3.0
3.1416 
314.16e-2
0.31416E1 
34e1​

Comments begin with -- and continue to the end of the line. For example,

a = 1; -- remark

See the article about the syntax of expressions in the blocks:

Unlike Lua, the TRIK Studio language is statically-typed, that is, the type of each expression and each variable must be known at compile time. Moreover, the language does not require (and does not even allow!) to explicitly write the types of variables. It uses automatic type inference for the use of variables.

For example, environment "understands" from the expression a = 1 that type of a is integer.

See the article about the syntax of expressions in blocks:

TRIK Studio has only one built-in constant. It can be used in the same way as sensor variables, but its value cannot be changed.

In mathematical expressions, you can use the functions available for any platform.

Add blocks to the scene

You can add blocks to the scene in TRIK Studio in three ways:

1. Drag and drop the corresponding icons from the palette of elements onto the diagram.

2. Using mouse gesture.

3. When creating a new connection between blocks using a linker.

Drag and drop from the palette

Left-click on the necessary block located in the Palette panel. Without releasing the mouse button, move the block onto the scene.

Use mouse gestures

Draw on the scene a special image of the block with the Right mouse button. The block appears in the center of the drawn image.

Gestures can be drawn with a few strokes. The gesture input ends if the strokes have not been drawn for some time (you can set the time in the settings window on the Behavior tab).

Available conditional images can be found in two ways:

1. In the "Mouse Gestures" window, which opens through the main menuTools → Mouse gestures.

2. In the tooltip that appears when you hover over a block in the Palette panel.

Add block when creating a new connection

1. Start creating a connection using the linker (a colored circle to the right of the block that appears after the block is selected) and release the left mouse button when the cursor is on an empty section of the diagram.

2. In the menu that appears, select "Create new element". A new menu with blocks will appear.

3. Select the block you need.

Delete block

Deleting a block from the scene is possible in two ways:

1. Select the block with the left mouse button and then click the "Delete" button on the keyboard.

2. Right-click on the block and select "Delete" in the menu that appears.

Delete several blocks

1. Select the necessary blocks in one of the following ways.

1.1. Hold down the "Ctrl" button and right-click the necessary blocks.

1.2. Right-click on an area in the scene with the necessary blocks.

2. Delete the selected blocks in one of the following ways.

2.1. Press the “Delete” button on the keyboard.

2.2. Right-click on any selected block and select "Delete" from the menu that appears.

Replace block

To replace the block on the scene:

1. Right-click on the block and select "Replace by..." in the menu that appears.

2. Select the block that you want to put instead of from the list.

The list of available blocks depends on the chosen robotics kit and on the robot model (real robot or 2D model simulation). Blocks unavailable for the current kit are not shown at all, and blocks inaccessible for this model within the same platform are shown in gray and are not available for dragging onto the scene.

Common blocks for all platforms are presented below. A program using only these blocks will be executed on any platform without any changes.

A list of blocks specific to a particular robotics kit can be found in the relevant sections:

• TRIK

• LEGO EV3

• LEGO NXT

• Geoscan Pioneer Quadcopter

List of common blocks

Initial Node

The starting point for program execution.

Each diagram should have only one such block. There should not be any incoming links in it, and there should be only one outgoing link from this element.

The process of diagram interpretation begins with this block.

Final Node

End of the program.

If the program consists of several parallel execution sections, reaching this block completes the corresponding execution section.

This block cannot have outgoing links.

Variable Initialization

A block for declaring a new variable and setting a value for it. The same operation can be performed using the Expression block, but this block makes the program more clear.

Properties

Condition

Separation of program execution in accordance with a given condition.

This block must have two outgoing connections, at least one of which must have the value of the Condition parameter set: true or false.

Properties

End if

Indicates merging of two branches of a conditional statement. It does not perform any actions but is useful for ensuring the structure of the program. It does not perform any actions but is useful for ensuring the structure of the program. If you adhere to the rule that all branches of the "Condition" or "Switch" operators converge on such a block, this will significantly increase the chances that the generator will be able to generate code in text language without goto statements.

Pre-conditional Loop

A loop with a precondition is a loop that is true so far for some condition specified before it starts. This condition is checked before the loop body is executed, so the body may not be satisfied even once (if the condition is false from the very beginning).

Properties

Loop

Block that provides the execution of a sequence of blocks several times. The number of repetitions is set by the value of the Iteration parameter. The block must have two outgoing connections, one of which must be marked with the value “body” (that is, the value of the “Condition” parameter the connection must have “body”). Another connection coming from the “Cycle” block should remain unmarked: it will go through when the program passes through the “Loop” block the specified number of times. Infinite loops and loops of the form while / do and while are organized without using this block, looping the control flow using links. An exit from such a loop is carried out using the “Condition” block.

Switch

A condition with several alternatives.

In the "Expression" parameter, you can specify an arbitrary expression (for more details, see the section "Syntax of expressions"), based on the value of which the further path of the diagram interpretation will be selected.

This block must have several outgoing links. All relations, except one, should be marked with an elementary value (string, number, etc.), which can take an expression (the value is simply written in the Condition property of the connection). One of the links should not be marked: it jumps if the expression is not equal to any of the listed values.

Expression

Evaluate the value of the specified expression. Initialization of variables is also allowed.

For more information about the