Comment 10 for bug 367151

I just observed one very obvious flaw in my implementation - that range of zooming is being checked in the function that sets it
i.e., WGLWaveformViewer::eventFilter() sets the zooming limits.
While the better approach will be to check the range centrally, somewhere in ratecontrol.cpp or enginemaster.

Also,
1. as Owen mentioned - increase zooming more and
2. as Sean pointed out, pre-roll markers (and other non-music data) should disregard the zoom level when rendering so they're always the same size.

I'll include all above changes in next patch.

Few more things I would like to discuss:
I noticed some talks regarding +/- buttons on waveform for zooming, is that on hit list too ?
If yes, I'll be needing some help with making pixmaps of '+' and '-' for different skins.

I would also suggest disabling zooming with pitch slider (as Jus mentioned in https://bugs.launchpad.net/mixxx/+bug/325377/comments/22).