http://bugs.winehq.org/show_bug.cgi?id=14045
--- Comment #5 from Alexander Sabourenkov screwdriver@lxnt.info 2008-08-05 12:30:27 --- Tracked this one to the fact that wine never returns PixelFormats with PFD_GENERIC_FORMAT flag set. The flag, as far as I understand MSDN, means software rendering, 'generic implementation' in msdn-speak.
I suspect that Windows always return at least one visual with this flag set, and Sketchup tries to use 'most-likely working' PixelFormat at the first run, so that user can open Preferences window and enable acceleration.
Not sure what is the correct course of action here. Code that sets flags in X11DRV_DescribePixelFormat does this incorrectly, I think. For example, PFD_GENERIC_ACCELERATED means the PixelFormat is backed by driver as opposed to 'generic implementation' and thus is hardware-accelerated, but the code sets the flag on 'Slow' visuals/fbformats. PFD_SUPPORT_GDI is removed in the code if visual is double-buffered, but msdn only states that _their_ 'generic implementation' does not provide PixelFormats with both those flags set.
On the other hand, there is no 'generic' implementation present in X11 at all times, and there's no way to know what current implemenation means by 'Slow' caveat.
Need to think more about all this.