---
title: "Terminology"
canonical: "https://docs.cuesystem.com/space/CVCHELP/498533122/Terminology"
format: markdown
---
> Macro (toc)

---

# API

An application programming interface (API) is an interface that defines the ways by which an application program may request services from libraries and operating systems. An API determines the vocabulary and calling conventions the programmer should employ to use the services. It may include specifications for routines, data structures, object classes, and protocols used to communicate between the requesting software and the library.

# Collection of graphic objects

The collection of graphic objects is a graphic module containing more graphic class declarations. So it is a set of graphic classes included in one graphic module.

# Embedded classes

### Class _Animation

This class represents animation. The animation is a set of pictures using the alpha channel.

### Class _AudioOutput

The typical touch panel is equipped with one audio output named AudioOutput which allows the play of sound. Audio output is represented by class _AudioOutput.

### Class _Display

One or more displays are defined for CUEunit (touch panel). The display is a graphical device represented by class _Display and typically it is the LCD screen of the touch panel. The standard touch panel includes one device Display. Display commands are used with prefix display name, for example, Display.On().

### Class _Font

This class represents a font.

### Class _Picture

This class represents a picture. It includes status functions and drawing functions. Drawing functions allow changing a picture by a program. All changes are provided in operating memory only and the primary resource picture isn't affected.

### Class _Sound

This class represents a sound. The class has no functions.

# Graphic objects

The graphical system of the XPL<sup>2</sup> language is based on graphic objects. Every graphic object is an instance of a graphic class created through IDE. Graphic classes are stored in the graphic module. In the case of the creation of a new graphic object, a graphic module is created automatically.

Inheritance of BaseGraphicWindow:

```visualbasic
BaseGraphicWindow Inherits BaseGraphicClass
```

### BaseGraphicClass

Class BaseGraphicClass has drawing functions, functions to handle events, and other functions. Functions for handling events are automatically called on various occasions and they have special meaning. Drawing functions may be called only in function OnDraw and in functions called from function OnDraw. Other functions can be called whenever. All coordinates are relative to the left top corner of an object. Coordinate X grows right, coordinate Y increases downwards.

### Graphic object

The graphic object is an instance of a class derived from BaseGraphicClass and it is a separate imaging element (for example button). It can be inserted into the graphic window and it can't contain other objects.

Inheritance of user Graphic Objects:

```visualbasic
GraphicClass UserGraphicObjectClassName Inherits BaseGraphicClass
```

### BaseGraphicWindow

Class BaseGraphicWindow inherits the BaseGraphicClass and it can include other objects. In addition, it has some features specific to windows - it has no parents and it is activated on a specified display. A window is a graphic object derived from the base graphic window.

### Graphic Window

The graphic window is an instance of a class derived from BaseGraphicWindow and it is the first object inserted to touch panel layout during graphic design using a graphical editor. The graphic window contains other graphic objects.

Inheritance of user Graphic Windows:

```visualbasic
GraphicClass UserGraphicWindowClassName Inherits BaseGraphicWindow
```

# IDE

An integrated development environment (IDE) also known as an integrated design environment or integrated debugging environment is a software application that provides comprehensive facilities to computer programmers for software development. An IDE consists of a source code editor, a compiler, build automation tools, and a debugger.

# Object

Objects are entities that combine state (i.e., data), behavior (i.e., functions), and identity (unique existence among all other objects). An object must be explicitly created based on a class and an object thus created is considered to be an instance of that class.

# Opacity

A low opacity means high transparency. High opacity means low transparency. The opacity is from 0 (fully transparent, invisible) to 255 (fully opaque). The opacity enables to show of a background like a glass (translucency), an effect not possible with simple binary (transparent or opaque) transparency. It allows easy image compositing.

# Resources

XPL<sup>2</sup> application often includes data that do not have source code. Such data is referred to as a project resource and it can include animations, fonts, pictures, sounds, texts, and ir data. Each data is internally represented by an instance of a built-in class. The instance is named by a programmer when entering data into the project. Each class can have functions that can be used during programming. Resources are language-dependent (except for ir data).

# Text wrap

It is an automatic placement of a word on the following line when the entire word will not fit on the current line.