[Chimera-users] how to tell chimera to use the local python installation
gregc at cgl.ucsf.edu
Thu Jun 15 16:40:03 PDT 2006
On Thu, 15 Jun 2006, Sabuj Pattanayek wrote:
> With the release of xorg-7.1.1 and mesa-6.5 I finally have direct
> rendering for my i855gm/i810 intel video device under linux. However I
> get lots of flickering of an object inside of the chimera display window
> when I rotate or move the object.
> I don't have this issue with pymol (compiled against the system python)
> and vmd (compiled against C/C++ opengl bindings?) or even glxgears.
> Perhaps I can workaround this problem by telling Chimera to use the
> local python installation? How is this done?
The current version of chimera uses a modified Python, so it is not
possible to substitute in a different one. And even if you could, it
shouldn't make any difference. The difference is hidden somewhere in the
The flickering is caused by not updating the contents of the graphics
window during the display's vertical retrace. This used to be on by
default, but I guess that is no longer the case. Maybe Mesa has
environment variable like NVidia's __GL_SYNC_TO_VBLANK, which sets the
There are also OpenGL extensions, MESA_swap_control and
GLX_SGI_swap_control, that control the effect you're seeing. If one of
those extensions is supported by your setup, you should see it listed in
the output of the glxinfo command. Unfortunately, chimera doesn't use
them yet. Please use the "Report a Bug" dialog available via the Help
menu and send me the output of the glxinfo command, so I have a bug to log
the fix against.
UCSF Computer Graphics Lab
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