mattercontrol/research/linux-migration.md

MatterControl Linux Migration Notes

Current State

The project is a C# .NET 6.0 desktop application for 3D printing control. It currently targets Windows but has cross-platform foundations.

Build Errors on Linux

error NETSDK1100: To build a project targeting Windows on this operating system, set the EnableWindowsTargeting property to true.

Affected projects:

• MatterControl.Winforms/MatterControl.Winforms.csproj
• Submodules/agg-sharp/PlatformWin32/PlatformWin32.csproj
• Submodules/agg-sharp/Tests/TestInvoker/TestInvoker.csproj

Architecture Overview

Platform Abstraction Layer

The project uses a provider pattern for platform-specific functionality:

1. Window Providers (in Program.cs:167-172):

   • MatterHackers.GlfwProvider.GlfwWindowProvider - Cross-platform (GLFW)
   • MatterHackers.MatterControl.WinformsSingleWindowProvider - Windows-only (WinForms)

2. Platform Features (Program.cs:276):

   • MatterHackers.MatterControl.WindowsPlatformsFeatures - Windows implementation

Key Projects

Project	Target	Notes
MatterControl.csproj	net6.0-windows	Main entry point, needs net6.0
MatterControlLib.csproj	net6.0-windows	Core library, needs net6.0
MatterControl.Winforms.csproj	net6.0-windows	WinForms provider, Windows-only
GlfwProvider.csproj	net6.0	Already cross-platform!
PlatformWin32.csproj	net6.0-windows	Windows-only

GLFW Provider (Cross-Platform)

Located at Submodules/agg-sharp/Glfw/GlfwProvider.csproj - already targets net6.0 and provides cross-platform windowing via GLFW library.

Windows-Specific Code in Program.cs

// P/Invoke - Windows only
[DllImport("kernel32.dll")]
static extern EXECUTION_STATE SetThreadExecutionState(EXECUTION_STATE esFlags);

[DllImport("Shcore.dll")]
static extern int SetProcessDpiAwareness(int PROCESS_DPI_AWARENESS);

These are used for:

• Preventing system sleep during prints (KeepAwake)
• High-DPI display support

Windows-Specific Code in WindowsPlatformsFeatures.cs

• System.Media.SoundPlayer - Windows-only audio
• WindowsFormsClipboard - WinForms clipboard
• WinformsEventSink.AllowInspector - Debug inspector
• InspectForm - WinForms debug form

Migration Strategy

Phase 1: Project File Changes

1. Change target frameworks from net6.0-windows to net6.0:

   • MatterControl.csproj
   • MatterControlLib.csproj

2. Use conditional project references:

   <ProjectReference Condition="'$(OS)' == 'Windows_NT'" Include="MatterControl.Winforms.csproj" />
   

3. Remove or conditionally exclude:

   • PrinterDriverInstaller (Windows driver installer)
   • MatterControl.Winforms reference on Linux

Phase 2: Code Changes

1. Program.cs - Add platform detection:

   if (RuntimeInformation.IsOSPlatform(OSPlatform.Linux))
   {
       AggContext.Config.ProviderTypes.SystemWindowProvider =
           "MatterHackers.GlfwProvider.GlfwWindowProvider, MatterHackers.GlfwProvider";
       // Use Linux platform features
   }
   

2. Create LinuxPlatformFeatures.cs:

   • Implement INativePlatformFeatures for Linux
   • Handle clipboard via X11/Wayland or cross-platform library
   • Stub out Windows-specific features (sound, camera)

3. Conditional P/Invoke:

   static void KeepAwake(bool keepAwake)
   {
       if (!RuntimeInformation.IsOSPlatform(OSPlatform.Windows))
           return;
       // Windows implementation
   }
   

Phase 3: Dependencies

1. GLFW native library: Need libglfw.so on Linux

   # Debian/Ubuntu
   sudo apt-get install libglfw3
   
   # Or via Nix
   pkgs.glfw
   

2. OpenGL: Need OpenGL drivers

   sudo apt-get install libgl1-mesa-dev
   

3. Serial ports: Already have System.IO.Ports package (cross-platform)

Phase 4: shell.nix Updates

{
  pkgs ? import <nixpkgs> { },
}:

pkgs.mkShell {
  packages = with pkgs; [
    dotnet-sdk_8
    glfw
    libGL
    xorg.libX11
    xorg.libXcursor
    xorg.libXrandr
    xorg.libXinerama
    xorg.libXi
  ];

  LD_LIBRARY_PATH = pkgs.lib.makeLibraryPath [
    pkgs.glfw
    pkgs.libGL
  ];
}

Files to Create

1. MatterControl.Linux/LinuxPlatformFeatures.cs - Linux platform implementation
2. MatterControl.Linux/MatterControl.Linux.csproj - Linux-specific project (optional)

Files to Modify

1. MatterControl.csproj - Change TFM, conditional references
2. MatterControlLib/MatterControlLib.csproj - Change TFM
3. Program.cs - Platform detection, conditional code
4. shell.nix - Add native dependencies

Alternative: Minimal Changes Approach

Instead of full platform abstraction, use #if directives:

#if WINDOWS
    // Windows-specific code
#else
    // Linux/cross-platform code
#endif

And build with:

dotnet build -p:DefineConstants=LINUX

Open Questions

1. Should the GLFW provider be the default for all platforms?
2. What Linux-specific features need implementation (file dialogs, etc.)?
3. Is the old PlatformGtk worth updating or should we focus on GLFW?
4. Should we create a separate solution file for Linux builds?