Uploaded image for project: 'Qt'
  1. Qt
  2. QTBUG-70387

Rendering bug discovered with the usage of enviroment variable QT_XCB_NATIVE_PAINTING using QT5.11.1

    XMLWordPrintable

    Details

    • Platform/s:
      Linux/X11
    • Commits:
      26462f9c4c31a691cf98526c4cea23afee79bcc6

      Description

      Recently we discovered that with the Qt5 there is performance degradation when
      Qt5 application is being used over the NoMachine that us caused by the fact
      that Qt5 removed the support for the native renderer and switched to something
      similar to the 'raster' rendered from the Qt4. After some research we found
      out that starting from the Qt 5.10 (we actually tried 5.11.1) the native
      rendered can be re-enabled with the environment variable
      (QT_XCB_NATIVE_PAINTING). Doing that speeds up the rendering of all our
      widgets over the NoMachine, but it causes issues with the rendered view .
      Basically what happens is that there is a part of the canvas that is not being
      rendered. See sample view attached.
      By default , without this environmental variable QT_XCB_NATIVE_PAINTING),
      rendering using same codebase works fine but slow on nomachine.

      Please look into this issue on priority.
      Regards

      Amarpal Singh
      Mentor graphics

        Attachments

        1. example1.png
          example1.png
          10 kB
        2. example2.png
          example2.png
          10 kB
        3. example3.png
          example3.png
          7 kB
        4. expected.png
          expected.png
          9 kB
        5. failed.png
          failed.png
          7 kB
        6. main7.cpp
          2 kB
        7. main7.pro
          0.0 kB
        No reviews matched the request. Check your Options in the drop-down menu of this sections header.

          Activity

            People

            • Assignee:
              esabraha Eskil Abrahamsen Blomfeldt
              Reporter:
              amarpalsingh Amarpal Singh
            • Votes:
              2 Vote for this issue
              Watchers:
              12 Start watching this issue

              Dates

              • Created:
                Updated:
                Resolved:

                Gerrit Reviews

                There are no open Gerrit changes