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Re: How to best get smooth scrolling in X?

Mads Bondo Dydensborg wrote:
> On Wed, 27 Nov 2002, Steve Baker wrote:
>>>Thanks. Would it be your impression that the OpenGL drivers typically wait 
>>>for the vertial retrace before swapping?
> Sorry, my questions seems to keep beeing ambiquios. What I meant to add 
> was "by default".

Ah - then no.  By default the sync-to-vertical-retrace is DISABLED so
swap happens immediately.

This seems like totally the wrong default to me - but the problem is
that people like to measure how fast games are running by looking at
the frame rate.   With sync-to-vertical-retrace turned on, you can 
never get more than the frame rate of your monitor...60Hz or whatever.

Since graphics card manufacturers like to show off what wonderful 
speeds they can produce, they turn off the vertical sync by default.

> It is clear from your answer that the opposite seems to be the default for 
> Nvidia.

Yep - and for every other PC graphics card I've ever heard of.

Silicon graphics workstations running IRIX have the opposite default - 
but PC's are never set like that.

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