New Cross-Platform 2D Framebuffer

Revision as of 09:05, 24 March 2011 by Sean (talk | contribs) (new layout)

Cross Platform Framebuffer

Impact Difficulty
high low

BRL-CAD displays its raytracing output as it is generated by using a framebuffer. Currently BRL-CAD has specific framebuffers for X11 Opengl (ogl), Windows OpenGL (wgl), and raw X11 (X), in addition to a variety of more special purpose and experimental framebuffers. A single, high performance, cross platform framebuffer is of interest to BRL-CAD.

This task, could utilize a cross-platform application framework such as Qt or OGRE or it could utilize some other approach. In addition to Qt or OGRE, another candidate could be the pxCore library ( ) or GLUT.

Whatever the solution, it would ideally be implemented in such a way that it can be embedded into a Tk window and be a "drop in replacement" for existing stand-alone and embedded graphical framebuffers on multiple platforms. Hardware acceleration should not be required, but leveraging it automatically when it's available would be great.

  1. Review current framebuffer code and related code (in particular, isst) to identify features needed for a framebuffer
  2. Identify approach (Qt, OGRE, pxCore, custom code, etc)
  3. Implement working code, including:
    • per-scan-line drawing - display update should not have to wait for a completed raytrace
    • good drawing performance - a fast raytrace should display quickly, not have to wait for framebuffer drawing to catch up
    • keyboard and mouse input (there is some)
  4. Can start development with reading in lines from a pix file instead of hooking in the raytracer in order to optimize display performance, but should progress to using the raytracer.
  5. Testing (ideally cross platform) - load a .g model, raytrace it and display the results. Ideally integrated into MGED.

A good proposal for this task will need to spell out a fair number of specifics and should do some homework - "research and implement framebuffer code" would be a weak submission. The X11 framebuffer (if_X24.c) would be good code to review when developing a proposal for this task.


  • Familiarity with C and C++
  • (optional) Familiarity with cross platform graphical drawing APIs and issues


  • src/libfb
  • include/fb.h
  • include/fbio.h
  • include/fbserv_obj.h