I just spent an unspeakable number of days typing to produce something that sounds very un-impressive: an FLTK widget that can display an image. The docs and code live here. The big difference from the usual image-drawing widget is that this one uses OpenGL internally, so after the initial image load, the common operations (drawing, redrawing, panning and zooming) are very fast. I have high-resolution images in my projects, and this will make my tools much nicer.

Three separate interfaces are available:

  • C: core library and GLUT application
  • C++: FLTK widget
  • Python: FLTK widget for pyfltk

The FLTK widgets have built-in interactive panning/zooming, and the library can draw line overlays. So nice applications can be built quickly.

I already added some early disabled-by-default support into the mrcal-stereo tool to visualize the rectification and report sensitivities: