Smooth scrolling

Max Schwarz Max at x-quadraht.de
Wed Apr 7 11:30:26 PDT 2010


Am Mittwoch 07 April 2010 16:13:09 schrieben Sie:
> First, you could have one factor which governs how many valuator scroll
> steps are needed to trigger one button scroll event, as discussed above.
> This would need to be enforced by the driver. If a mouse is clicky, it
> may be 1 or the driver would multiply it to match some target value like
> 100. The main question is whether apps need to or shouldn't know that
> factor. I think that's what Eric meant.
Eric wanted to scale the reported valuator value so that it is in relative 
units to the old clicks, if I understood correctly.
But I see your point, it might be better (and more generic) to report the 
scrolling in unspecified "device-units" and give additional information to the 
toolkit on how to interpret the valuator.
There is a "resolution" field in the XI2 query response that could be used, 
though the comment next to it says it is intended to be in "units/m" 
(XI2proto.h:184), while we want "units/scrollclick" or something like that.

If we can use that field then it's not much more work. Toolkits can recognize 
the right valuator through the label and get the associated resolution, all 
via XI2.

Max


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