Unable to run on Linux with Mono

TheRealNOIG commented 5 years ago

Unable to run my program in Linux using mono. I get an exception that OpenGL cannot find systemDLL opnegl32.dll

/Debug$ mono Test2.exe
Creating OpenGL instance

Unhandled Exception:
System.TypeInitializationException: The type initializer for 'OpenGL.Gl' threw an exception. ---> System.DllNotFoundException: opengl32.dll
  at (wrapper managed-to-native) OpenGL.Gl+NativeMethods.glxGetProcAddress(string)
  at OpenGL.Gl+GetProcAddressX11.GetProcAddress (System.String function) [0x00000] in <118e14bf4e6e43458e7031331eb2b4d0>:0 
  at OpenGL.Gl.GetAddress (System.String function) [0x0005a] in <118e14bf4e6e43458e7031331eb2b4d0>:0 
  at OpenGL.Gl.GetExtensionDelegate (System.String name, System.Type signature) [0x00000] in <118e14bf4e6e43458e7031331eb2b4d0>:0 
  at OpenGL.Gl.GetDelegate (System.String name, System.Type signature) [0x00000] in <118e14bf4e6e43458e7031331eb2b4d0>:0 
  at OpenGL.Gl.ReloadFunctions () [0x0007b] in <118e14bf4e6e43458e7031331eb2b4d0>:0 
  at OpenGL.Gl..cctor () [0x0007f] in <118e14bf4e6e43458e7031331eb2b4d0>:0 
   --- End of inner exception stack trace ---
  at OpenGL.Platform.Window.CreateContextFromWindow (System.IntPtr window, System.Boolean fullscreen) [0x00049] in <1a9c11f978ab4564b09d050cd056057e>:0

giawa commented 5 years ago

Can you make sure that the OpenGL.dll.config file is alongside OpenGL.dll? OpenGL.dll.config contains the information that Mono needs to map the calls to libGL.so.1 on Linux.

TheRealNOIG commented 5 years ago

Yes OpenGL.dll.config is alongside OpenGL.dll.

My mono compiler version version is 5.12.0.301

giawa commented 5 years ago

Very strange. I can tell that mono is still trying to look for opengl32.dll (which is the wrong library to use) due to the error message in your exception here: "System.DllNotFoundException: opengl32.dll". So it seems like that .dll.config file is not being used properly. Unfortunately, I don't have a Linux installation right now, so I am unable to debug this issue. Do you have any time to try to debug what is going on?

giawa commented 5 years ago

I'm going to try installing a Linux VM, but it will likely be a day or two before I have time to address this. Sorry for the delay, and definitely let me know if you find a work around/solution. Thanks!

TheRealNOIG commented 5 years ago

I fixed this problem by changing the dll map to target libGL.so.1. Because according to https://www.mono-project.com/docs/advanced/pinvoke/dllmap/

... The element takes two attributes:

dll: This should be the same string used in the DllImport attribute. This can be prefixed with i: to specify that name matching should be done in a case-insensitive fashion.
target: This should be the name of the library where the function can be found: this name should be suitable for use with the platform native shared library loading routines (dlopen etc.).

Here are the changes I made to the config file

<configuration>
    <dllmap dll="opengl32.dll">
        <dllmap os="linux" target="libGL.so.1"/>
        <dllentry os="windows" target="opengl32.dll" />
        <dllentry os="osx" target="opengl32.dll" />
    </dllmap>
</configuration>

But im now getting this error

Creating OpenGL instance
Stacktrace:

  at <unknown> <0xffffffff>
  at OpenGL.Gl.GetAddress (string) [0x000cd] in <67e44ecdff4b47748523e7986adaa0e4>:0
  at OpenGL.Gl.GetExtensionDelegate (string,System.Type) [0x00000] in <67e44ecdff4b47748523e7986adaa0e4>:0
  at OpenGL.Gl.GetDelegate (string,System.Type) [0x00000] in <67e44ecdff4b47748523e7986adaa0e4>:0
  at OpenGL.Gl.ReloadFunctions () [0x00034] in <67e44ecdff4b47748523e7986adaa0e4>:0
  at OpenGL.Gl..cctor () [0x0009c] in <67e44ecdff4b47748523e7986adaa0e4>:0
  at (wrapper runtime-invoke) object.runtime_invoke_void (object,intptr,intptr,intptr) [0x0001e] in <b0e1ad7573a24fd5a9f2af9595e677e7>:0
  at <unknown> <0xffffffff>
  at OpenGL.Platform.Window.CreateContextFromWindow (intptr,bool) [0x00049] in <1a9c11f978ab4564b09d050cd056057e>:0
  at OpenGL.Platform.Window.CreateWindow (string,int,int,bool) [0x00091] in <1a9c11f978ab4564b09d050cd056057e>:0
  at GzreEngine.Engine.Core.Window..ctor () [0x00006] in <cfbb2c895f9e436d9d2e12a323dba916>:0
  at GzreEngine.Program.Main (string[]) [0x00010] in <cfbb2c895f9e436d9d2e12a323dba916>:0
  at (wrapper runtime-invoke) <Module>.runtime_invoke_void_object (object,intptr,intptr,intptr) [0x0004e] in <cfbb2c895f9e436d9d2e12a323dba916>:0

BTW the program successfully creates the window but crashes before the screen is cleared. Image: https://imgur.com/a/sA13gV3

TheRealNOIG commented 5 years ago

I fixed the issue. I don't know if this also works for mac as I don't have one to test it on. I also haven't tested this on Windows as I need to head to work now.


<configuration>
    <dllmap dll="opengl32.dll">
        <dllentry os="linux" dll="libGL.so.1" />
        <dllentry os="osx" target="opengl32.dll" />
        <dllentry os="windows" target="opengl32.dll" />
    </dllmap>
</configuration>

TheRealNOIG commented 5 years ago

Made a change to osx and Widnows to point to dll not target. My test on windows and Linux work as expect. I have created a merge request to get these changes added to the repo. https://github.com/giawa/opengl4csharp/pull/30

giawa commented 5 years ago

Okay, so I think it was just a typo in the dll.config file, correct? dllentry should have been dllmap? Thanks for taking a look!

giawa / opengl4csharp

Unable to run on Linux with Mono #29