[boost] GUI coordinate units (Was: GUI foundations)

From: Vladimir Prus (ghost_at_[hidden])
Date: 2005-10-04 08:20:12

Stefan Seefeld wrote:

>> Just think of the many places you'll need to deal with geometry
>> (rectangle/point/size), and converting from one type of unit (px to cm,
>> cm to in, etc) to another.
> 
> I agree. In particular, I'd strongly suggest to draw a clear distinction
> between physical dimension and resolution. Most current GUIs did get that
> wrong, I believe in that they conditioned us all to think of size when
> talking about number of pixels.
> 
> The consequence is similar to the Y2K bug: applications won't easily adapt
> to displays with different resolutions (well, may be within a narrow
> range), and so a lot of efford is needed on a high (application) level to
> compensate for that lack of abstraction.

Can you elaborate on this? For explicit 2D graphics "pixel" is already just
a convention, since you can scale that as you like. And for window layout,
well, you should not do manual window layout at all. GUI library should
select font size and other things, and everything will be laid out. What
problems do you have in mind?

- Volodya