"Brian S. Julin" wrote:
>
> On Mon, 4 Dec 2000, Stefan Seefeld wrote:
> > But I agree with the proposition: why not provide a function
> > to specify scaling factors (possibly independently for X/Y)
> > to be used *inside* gii such that the reported event position
> > already contains that scaling.
>
> Basically to avoid bloat... If you support any kind of simple scaling,
> then someone will want to support more complex scaling, e.g. scaling that factors in
> the size or dpi of the visual, or that adds dead-zones or sensitivity curves
> for joysticks, etc. Then you have to either add that into LibGII, or you
> have to deal with one way of doing it being in LibGII and another way being
> external.
uhm, wait. The way it is done now suggests that the coordinates as reported
by an event are just pixels. So you get your dpi dependency automatically.
What my proposition boils down to is in fact to make position coordinates totally
independent from pixel coordinates.
sensitivity to events is an entirely different story, and should be dealt with
on top of GGI, as it is the responsibility of a region manager (you want to 'pick'
a target object which intersects with the position, for whatever definition you use
for 'intersection').
> > Should be fairly trivial to add,
> > but makes a nice convenience function...
>
> What you're wanting is a "event filter". EvStack, which was planned
not at all. The point is that now at least for the X targets I get some little
pointer drawn on the visual, indicating that there is indeed a link between the
position and pixel indexes. I'm proposing that GGI allows scaling factors to
decouple both concepts, much in line with the original question about 'accelerating'
the mouse movement arbitrarily.
Event filtering, again, is a complex thing, and needs to be done in the context of
a 'scene graph', or a set of windows, or whatever concept you use in your UI. It's
the region manager's task.
Regards, Stefan
_______________________________________________________
Stefan Seefeld
Departement de Physique
Universite de Montreal
email: [EMAIL PROTECTED]
_______________________________________________________
...ich hab' noch einen Koffer in Berlin...
