Issues that might be related to MonoGame

Christian24 · July 22, 2014, 1:57am

Hi everyone,

First of all thank you for making MonoGame such an awesome alternative to XNA.

I recently noticed that my game on Windows Phone 8 is experiencing lots of crashes. I think they might be have been introduced by some MonoGame source code changes in recent months (as I only did very minor changes to the game code itself). I could be wrong, but I also was not able to find out more about the issues on the internet. Sadly I only have the 30 day overviews from the Dev Center.

The most crashes seem to be caused by UMThunkStub. The exception type is always c0020001.

The second most common issue is at SharpDX.Direct3D11.Device.GetFeatureLevel a NullReferenceException. I am not using that code in my game and so I deduce that it must be something inside of MonoGame.

I am a little helpless here. Any help is greatly apreciated.

Thanks,
Christian

LoveDuckie · July 22, 2014, 8:30am

For a start, that would be something relating to the SharpDX libraries that MonoGame uses for rendering with DirectX to that platform. Strange that it’s failing when calling that D3D API method though, I imagine that there is perhaps something either wrong with the device or the SharpDX libs themselves.

Perhaps it might be beneficial to upgrade the SharpDX libs that are you are using? The dlls should be packaged with the MonoGame ones that are being used with your project.

Nezz · July 22, 2014, 8:46am

Most of the crashes that do not involve MonoGame code seem to be related to the Game.Exit() using System.Windows.Application.Current.Terminate(). UMThunkStub is one such crash.

THe GetFeatureLevel exception seems to be related to resuming.

Tom · July 23, 2014, 1:05am

This is probably related to this code:

github.com

MonoGame/MonoGame/blob/75014d0040efac92e73190234fcb6b1a79f3b545/MonoGame.Framework/Graphics/GraphicsDevice.DirectX.cs#L1223


      
          }
          
          /// <summary>
          /// Sends queued-up commands in the command buffer to the graphics processing unit (GPU).
          /// </summary>
          public void Flush()
          {
              _d3dContext.Flush();
          }
          
          private static GraphicsProfile PlatformGetHighestSupportedGraphicsProfile(GraphicsDevice graphicsDevice)
          {
              FeatureLevel featureLevel;
          
              if (graphicsDevice == null || graphicsDevice._d3dDevice == null)
                  featureLevel = SharpDX.Direct3D11.Device.GetSupportedFeatureLevel();
              else
                  featureLevel = graphicsDevice._d3dDevice.FeatureLevel;
          
              GraphicsProfile graphicsProfile;

… but we check for a null device there specifically.

What I suspect is that this happens after the app is put into the background and is then restored later. It probably ends up with an invalid graphics device. @Nezz ?

Christian24 · July 23, 2014, 9:56am

@LoveDuckie Is there anything specifically I have to do to update them? I just recloned the entire MonoGame repo just to be completely sure everything is up to date and I have not messed up anything.

@Nezz I need to look at my code more in detail to find out. One of the major problems is that I cannot reproduce any of those crashes.