WPF Glitchy Rendering

[AlaaAlHallaq]

Using CefSharp.WPF.Example to open web page with transparent background result in 2 things

1. Glitchy rendering.
2. Slow Scrolling.

please try opening the html 5 video test page from wpf sample:
https://tekeye.uk/html/html5-video-test-page

Thanks

[amaitland]

It's important to note that CefSharp is just a wrapper around the Chromium Embedded Framework (CEF). Closing this as upstream and as changes need to be made in CEF.

The CEF project has it's own issue tracker located at https://bitbucket.org/chromiumembedded/cef it is recommended you ask on https://magpcss.org/ceforum/index.php before opening an issue on the CEF issue tracker. The behavior you are seeing may be the expected default.

Before opening a new issue you should:

• Search open/closed issues to determine if the problem you are seeing has already been reported
• Test with a newer version if available, see https://github.com/cefsharp/CefSharp/blob/master/CONTRIBUTING.md#cefsharp-vs-chromium-embedded-frameworkcef for details on testing with the cefclient reference application.

If you do find an existing issue that matches this one or create a new one then post a link here for others to follow.

[amaitland]

The OffScreen rendering engine is being rewritten you can track the progress at https://bitbucket.org/chromiumembedded/cef/issues/2575/viz-implementation-for-osr

[AlaaAlHallaq]

@amaitland The issue is only appearing in CefSharp.WPF & CefSharp.WPF.Exmaple, neither CefSharp.WinForms.Example doen't nor CEF samples (CefClient,CefSample) have this issue.

[amaitland]

WinForms uses native rendering, entirely different. cefsimple doesn't support OffScreen rendering, so it's not an accurate comparison.

You didn't use the bug report template provided at https://github.com/cefsharp/CefSharp/blob/master/.github/ISSUE_TEMPLATE/bug_report.md#bug-report No mention of testing performed. No reference to cefclient being tested. As a result you get a saved response. This issue in all likelihood is still going to be a problem with CEF and it's OSR implementation.

You must test with cefclient --multi-threaded-message-loop --off-screen-rendering-enabled --enable-gpu Making sure to compare the exact same version of cefclient.

If the issue only reproduces with a transparent background then you'll have to factor that into your testing of cefclient.

[amaitland]

Testing with http://opensource.spotify.com/cefbuilds/cef_binary_75.0.6%2Bg90ecd35%2Bchromium-75.0.3770.80_windows32_client.tar.bz2 using cefclient --multi-threaded-message-loop --off-screen-rendering-enabled --enable-gpu and I see that scrolling is problematic and there's problems rendering the videos.

Adding --disable-gpu-compositing (as I've suggested in other cases like #2802 (comment)) and rendering greatly improves.

Best to report the issue on https://bitbucket.org/chromiumembedded/cef

[ilkayayas]

Here is the solution I used;

    public App()
    {
        CefSettings settings = new CefSettings();
        settings.SetOffScreenRenderingBestPerformanceArgs();

        Cef.Initialize(settings);
    }

[kani-rifluxyss]

This one did NOT work for me,

settings.SetOffScreenRenderingBestPerformanceArgs();

used these 2 lines and it is working!

cefSettings.CefCommandLineArgs.Add("disable-gpu", "1");
cefSettings.CefCommandLineArgs.Add("disable-gpu-compositing", "1");