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QNX Software Development Platform
QNX SDP is a cross-compiling and debugging environment, including an IDE and command-line tools, for building binary images and programs for target boards running the QNX OS 8.0.
Graphics
Screen Graphics Subsystem Developer's Guide
QNX Screen Graphics Subsystem is a graphics framework that provides all the functionality necessary to develop interactive user experiences.
Utilities and binaries
Screen includes some utilities and binaries to help with calibration, debugging, and demonstrating features.
screenshot
Capture content from a display

QNX Momentics IDE User's Guide
This User's Guide describes version 8.0 of the Integrated Development Environment (IDE) that's part of the QNX Tool Suite.
QNX Software Development Platform
QNX SDP is a cross-compiling and debugging environment, including an IDE and command-line tools, for building binary images and programs for target boards running the QNX OS 8.0.
- Quickstart Guide
- System Architecture
  The System Architecture guide accompanies the QNX OS and is intended for both application developers and end-users.
- OS Components & Operations
- Graphics
  - Gestures Library Reference
    The Gestures library provides gesture recognizers to detect gestures through touch events that occur when you place one or more fingers on a touch screen.
  - Image Library Reference
  - Input Events Library Reference
    The Input Events library provides the framework necessary for Screen Graphics Subsystem to communicate with your touch driver.
  - OpenWF Configuration Developer's Guide
    If you are integrating a new display, you must configure and provide the parameters of your display based on its specifications via the OpenWF Display Configuration API (Wfdcfg Library).
  - Screen Graphics Subsystem Developer's Guide
    QNX Screen Graphics Subsystem is a graphics framework that provides all the functionality necessary to develop interactive user experiences.
    - Application Development
      The Screen Graphics Subsystem is based on a client/server model where an application is a client that's requesting graphics services from the server (Screen). It includes a composited windowing system as one of these services, which means all application rendering is performed on off-screen buffers, which then can be later used to update the display.
    - Buffers
      A buffer is an area of memory that stores pixel data. Multiple buffers can be associated with a window or stream, but only one buffer can be associated with a pixmap.
    - Rendering
      Rendering refers to the generation of an image.
    - Windowing
      Windows are used to display content and to combine content produced by different renderers. Each of the different renderers can be in the same process, or in another process or processes.
    - Resource Sharing
      Resource sharing allows the access of buffers and their content within the same application and process, or between different applications and processes.
    - Displaying the contents of windows
      Displays are used to show the contents of your windows on physical hardware such as a computer monitor or a touchscreen display.
    - Cursor Movement
      There is more than one way to set up cursor movement between multiple displays.
    - Input
      One key aspect of Screen that enables the development of fully interactive user experiences is the functionality to support input events and to deliver input and notifications back to applications.
    - Event Handling
      Screen events, which include both input and general events, are associated with a given context and are generally handled in your main application's loop.
    - Asynchronous Notifications
      Applications can request to be asynchronously notified of specific Screen events by way of a sigevent.
    - Permissions and Privileges
    - Security policies
      This section on Screen security policies is intended for system integrators who are responsible for implementing and enforcing security policies that create and maintain a trusted execution environment.
    - Utilities and binaries
      Screen includes some utilities and binaries to help with calibration, debugging, and demonstrating features.
      - calib-touch
        Calibrate a touchscreen
      - cl10-pi
        An OpenCL 1.0 based demo for PI number generation with validation
      - cl11-ray
        Display fragment shader based ray tracer rendered content using OpenCL 1.1
      - clinfo
        Display information on OpenCL platforms and devices
      - disp-gles2-gears
        Demonstrate virtual display APIs using OpenGL ES 2.x
      - drm-*
        Start DRM (Direct Rendering Manager) for graphics hardware in the DRM family
      - drm-probe-displays
        Detect ports and pipelines for Intel graphics hardware
      - egl-configs
        Query and output the number of all supported framebuffer configurations for the specified EGL display
      - events
        Create a window manager connection to Screen and dump the events received as output to the console.
      - gles2-gears
        Display hardware-rendered content using OpenGL ES 2.x
      - gles2-maze
        Demonstrate how to use texture, as well as vertex and fragment shaders
      - gles2-teapot
        Demonstrate 3D rendering using OpenGL ES 2.x
      - gles3-gears
        Display hardware-rendered content using OpenGL ES 3.x
      - gltracelogger
        Record all OpenGL calls made by the target application
      - gltraceprinter
        A readable print of the trace (log) file generated from gltracelogger
      - mtouch
        The mtouch service starts the resource managers for touch functionality and loads the configuration
      - screen
        Start Screen services
      - screencmd
        Change properties of Screen objects
      - screeninfo
        Decode contents of binary files in /dev/screen for debugging
      - screenshot
        Capture content from a display
      - sharewin
        Demonstrate content sharing between windows
      - sw-vsync
        Display software-rasterized content
      - vg-tiger
        Display hardware-rendered content using OpenVG
      - vncserv
        VNC server for QNX Screen
      - Vulkan utilities and binaries
        Screen includes some utilities and binaries to help with calibration, debugging, and demonstrating features of Khronos's Vulkan APIs.
      - win-vsync
        Display software-rasterized content using multiple windows in a hierarchy
    - Debugging
      Debugging graphics isn't easy. Figuring out where the problem is can be challenging because of the many aspects and components when it comes to graphics. The goal of this chapter is to show the tools and techniques that you can use to help with your investigation.
    - Wayland on Screen
      Running Wayland on the Screen Graphics Subsystem provides a C library implementation of the core Wayland communication library.
    - Screen library reference
      Two important aspects to note when using Screen are function safety and function execution types.
    - Configuring Screen
      You configure libraries, drivers, and Screen parameters using the configuration file, graphics.conf.
    - Glossary
  - Video Capture Developer's Guide
    The video capture framework provides applications the ability to capture frames from a video input source. These frames can be passed to a graphics component such as Screen for display.
- Programming
- System Security Guide
  The QNX System Security Guide is intended for both system integrators who are responsible for the security of a QNX OS system and developers who want to create a QNX OS resource manager free from vulnerabilities.
- Utilities & Libraries
- Migrating to QNX OS 8.0
QNX Software in the Cloud
QNX Toolkit for Visual Studio Code
This User's Guide describes the QNX^® Toolkit for Visual Studio Code. The guide introduces you to the QNX Toolkit by explaining the QNX development environment and how to build, run, and debug your QNX^® Operating System (OS) applications and systems.
Typographical Conventions, Support, and Licensing
This section describes the typographical conventions used throughout the documentation, explains how to obtain technical support, and provides some information about licensing.

screenshot

Graphics and Screen4.0 (8.x)Screen Graphics Subsystem Developer's GuideAPIProgrammingUtilities

Capture content from a display

Syntax:

screenshot [-display=display_id]
           [-file=output_file]
           [-size=widthxheight]

Runs on:

QNX OS

Options:

-display=display_id

Specify which display the window will appear on by using display_id. You can specify display_id as one of the following:

an integer that identifies the display
an ID string that identifies the name of the display (id_string)

Whether by integer or by string, the display that you specify using display_id must be one of the displays that you've configured in the display subsections of the winmgr section in your configuration file (e.g., graphics.conf).

If you don't have any display subsections configured, or if you don't specify the display option, then screenshot uses the default display.

-file=output_file

Specify the filepath of the screenshot. If this option isn't specified, then the output will be stored in screenshot.bmp.

-size=widthxheight

Set the size, using integer values for width and height, of the screenshot (default is fullscreen).

Description:

The screenshot utility is a command-line tool that's used to capture content from a display. Once the content is successfully captured, screenshot saves the captured content in bitmap format in the specified filepath.

To run the screenshot utility:

Ensure that screen is running.
Run screenshot from a shell.

Page updated: December 04, 2024