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OS compositing with Stale buffer data... RRS feed

  • Question

  • OS XAML, and touch feedback compositing using stale buffers

    I am developing a windows store app to launch with 8.1.  It is a directx app that used a backgroundswappanel and which uses xaml for dialogs and popups.  When we moved to the 8.1 seeds, we noticed that often when the OS draws atop our direct x surface, that it uses a several frames old stale buffer resulting in stale results.  This happens when the os provides feedback over touch, and stylus or when charms come up, or any of our own XAML dialogs/popups. We noticed the Fresh Paint 8.1 app has similar issues, which are easy to reproduce.  This is atop a variety of x86 hardware with the latest drivers.  We have a good many videos but can't post them here, but will share them with someone from MS upon asking.

    It is even worse when using the background input thread.  

    Hope a fix is in the works as this makes it very hard to demo.




    Monday, August 5, 2013 5:17 PM

Answers

  • From your description this sounds like it may be a video driver issue rather than the latency issue I understood from your first post.

    Assuming this is incorrect rendering rather than a (known & expected) latency issue, I was not able to reproduce this on my desktop system. If you can upload a video to your SkyDrive and post a link that would help understand what you mean.

    --Rob

    Thursday, August 8, 2013 1:33 AM
    Moderator

All replies

  • Take a look at the new to Windows 8.1 Preview Direct3D low-latency presentation API

    I don't believe Fresh Paint is a DirectX app but is pure Xaml.

    --Rob

    Tuesday, August 6, 2013 5:17 AM
    Moderator
  • Actually the presentations at Build stated that Fresh Paint was DirectX (backgroundswappanel) + xaml for the tool bars. So it is using the same approach as we are, and exhibits the same issues (stale imagery when the os composites over interactions with the directx surface.

    We tried everything including that sample, with no luck in removing these issues.

    Tuesday, August 6, 2013 1:20 PM
  • This can easily be reproduced with FreshPaint 8.1 preview on a surface running 8.1. All you have to do is zoom in with fingers,paint, zoom out, mix this together for a few minutes and you will see stale data being composited by the OS, with fresh paint updating little tiles that are the correct imagery as you paint. unfortunately, I cannot upload a video to this forum.
    Tuesday, August 6, 2013 1:31 PM
  • From your description this sounds like it may be a video driver issue rather than the latency issue I understood from your first post.

    Assuming this is incorrect rendering rather than a (known & expected) latency issue, I was not able to reproduce this on my desktop system. If you can upload a video to your SkyDrive and post a link that would help understand what you mean.

    --Rob

    Thursday, August 8, 2013 1:33 AM
    Moderator
  • Fixed in RTM!!! Thanks!!
    Sunday, September 29, 2013 9:38 PM