Blender Git Loki

Added stepsize option for Pose ghosting draw. Patch provided by Roland
Hess.

In a comment on maillist I already mentioned a weird 0.5 in the code,
which I added to ensure correct rounding to integer frame numbers.
With a variable step size however, this won't work properly. You could
see it in the patch, because the ghost steps were animating.... they
should remain frozen, looks much nicer then. So I've added some fmod
voodoo here.