New initial clipping values have been selected,
and a clipping adjustment was added in F2 keymode
in et-edit and et-travel. This was done to make
the programs more compatible with OpenGL
implementations with lower Z-buffer resolution.
This version enables scaling the view without changing the distance from the observer, which is useful for stereoscopic mode for large (or small) objects. Combining of the left and right view in stereoscopic mode is modified so that flickering and copying framebuffers is avoided.