System information

• SolveSpace version: 3.x+
• Operating system: all supported

Expected behavior

Add FLTK GUI for SolveSpace.

NOTE: This is long term feature request! Do not close as wontfix, as it might be a place for new contributors.

Actual behavior

Actually SolveSpace GUI based on GTK2/3+, and there is some work on preparation for GTK4+ (#853). But GTK itself has many issue (with its ABI, theming, etc) which depends on each Linux distro.

Also there are requests on Qt5 GUI (#401) and ImGui GUI (#263).

Additional information

• FLTK supported Platforms/OS: Windows, macOS, Linux and other Unix, etc.
  • https://github.com/fltk/fltk/
• Custom FLTK widget themes:
  • https://github.com/Rangi42/tilemap-studio (more screenshots: https://hax.iimarckus.org/topic/7691/)
  • https://github.com/roukaour/viz-brain-visualizer
• Custom FLTK color themes (FLTK Dark Theme):
  • https://groups.google.com/g/fltkgeneral/c/3A5VC_854ok/m/sDpJsmuLBAAJ
• Custom FLTK widget schemes:
  • https://non.tuxfamily.org/wiki/NTK
• Cairo widget for FLTK and Qt:
  • https://github.com/user1095108/cairowidget