capturing images

If I’ve drawn an openGL scene, is there some way I can capture the scene to a bitmap file? I need to do certain area, lengh and radius of curvature calculations from my scene and openGL doesn’t support this

Use glReadPixels to read the framebuffer, and then use your own, or some third-pary, function to save it.

http://www.opengl.org/discussion_boards/ubb/Forum4/HTML/000182.html