Re: Zoom GUI in fltk backend

[Shai Ayal]

On Tue, Jun 30, 2009 at 11:11 PM, Søren Hauberg<address@hidden> wrote:
> tir, 30 06 2009 kl. 09:27 +0300, skrev Shai Ayal:
>> On Tue, Jun 30, 2009 at 8:15 AM, Søren Hauberg<address@hidden> wrote:
>> > No. When you zoom you change the values of 'xlim' and 'ylim', whereas
>> > 'min[x|y]' and 'max[x|y]' should be the extremas of the data. These are
>> > used to ensure that you don't zoom too far a way.
>>
>> Thanks for explaining:
>> So, perusing src/graphics.cc I think the right function to use is
>> get_children_limits as used in the code there, e.g.:
>>
>> Matrix kids = ap.get_children ();
>>
>> double min_val = octave_Inf;
>> double max_val = -octave_Inf;
>> double min_pos = octave_Inf;
>> get_children_limits (min_val, max_val, min_pos, kids, 'x');
>>
>> Note that this function is now static, so it would have to be
>> "un-statified" and the prototype would have to go to the
>> src/graphics.h.in files
>
> Ahh, okay, thanks. The attached patch does this. I don't really
> understand where which functions belong in all this graphics stuff, so I
> just removed the 'static' keyword and added the function at the end of
> 'graphics.h.in' without adding it to any class. This is probably wrong,
> and as Michael said, these values should probably be cached anyway.
> (Read: my solution to this part is still too hacky)
>
> That being said, the interface works quite nicely with the attached
> patch. I think this behaviour for zooming should be the default, but
> what do other people think?

I like this style of zoom (like google maps?). It could be default,
but why not make the "old" style an option?. But I'm not sure where
backend options should go.

Shai