Re: [Texmacs-dev] Drawing mode notes, vector diagrams, geometric construction

[Henri Lesourd]

Alvaro Tejero Cantero wrote:

> Hello,
>
>  
>
> > Thus we need to add one more step in the rotation mode : mark
> > the center (and then, we proceed as before, using a drag & drop
> > to perform the rotation itself).
> >    
>
>
> No, no no!!! please, use reasonable defaults and give then extra
> possibilities to the advanced users.
This is why the center is currently automatically set
to the barycenter of the points in the selection.

> Otherwise, to rotate something
> becomes tedious. The standard behaviour (see Inkscape) is:
>
> 1.- double click the object -> rotation mode
> 2.- either rotate it (use arrows at the corners) or
>     change the rotation center by moving the crosshair in the middle
>
> I think this is more convenient.
>
>  
We would need to completely revamp the interface
input language, then :-(, this is not very reasonable.

Currently, a simpler way to implement an extra
possibility to change the center of the rotation
would be to use a different command in the beginning.

The simplest way is probably, either :

(a) : left click / drag & drop the object ==> start the
     rotation, using the barycenter as the center of the
     rotation (this is the current implementation) ;

(b) : Shift-left click / Shift-drag & drop in the
     beginning : set the position of the center.
     Then a left click / drag & drop without Shift
     pressed starts the rotation itself (whether the
     center has been previously moved or not (in this
     latter case, the center of the rotation remains
     the barycenter)) ; we could also think about
     something a little bit different, namely we
     see the current center (as a cross, for example),
     and we could drag & drop it to change it, and in
     the same time, drag & dropping another point of
     the selection would start the rotation using the
     current center ;

Of course we also have the option of implementing
another "skin" for having a completely different
way of editing objects (in particular, one that
would more intuitive for beginners). But it should
be considered as a separate matter, I would say.

Anyway, as soon as the version 1 will be out,
I plan to do some work in unifying the edition
commands (especially the different modes) in a
better way.

But I don't yet see clearly what the best approach
should be for doing this (all the more because we
have several other problems related to that, i.e.
the problem of having some status lines that always
tells you the mode, and perhaps things like the
current cursor coordinates, etc.).


> > > > I had the same idea, but I don't know exactly the length of this
> > > > finer-grained movements (or perhaps should be proportional to the
> > > > length of the wide-grained movements, let's say 10x finer than the
> > > > usual movements ?).
> > > >        
>
> In Inkscape the arrow keys give these small nudges, of 2px by default,
> but configurable.
> Also the rotation snap angle (when you rotate with ctrl simultaneously
> pressed) is of 15degrees by default, but tunable. And "<" and ">"
> scale by 2px.
>
> I think all this things should be configurable, maybe the movements
> should be so even through the GUI.
>
>
>  
OK, so probably the best approach, then, is to keep the
first implementation of this feature as simple as possible,
and evolve it step by step when we get more feedback from
using the software.


Best, Henri