[kig] /: Make SegmentAxisType Equivalent to the Previous Macro

[David Narvaez]

On Wed, Jun 25, 2014 at 1:19 PM, Maurizio Paolini
<paolini at dmf.unicatt.it> wrote:
> I am not sure if I can "reply" to this mail... however here I am :-)

Sure you can :)

> Just one note: in order to implement interaction with (e.g.) geogebra
> it is not *imperative* that there is a one-one correspondence between
> geogebra objects and kig objects.  If a geogebra "perpendicular
> bisector" of points A and B is the axis of the segment AB, then
> there is nothing wrong in implementing it just that way:
> - construct the segment AB
> - use the propery "segment-axis" of the constructed segment
>
> Of course I know nothing about geogebra gb files, so perhaps I am missing
> something...
>
> Adding a new construction that is essentially already there seems only an
> added confusion for the user.
>
> On the other hand one could indeed modify the "Constructor" in order to allow
> the user to construct the "segment axis" *also* by clicking on the two points.
> In this way we shall have new functionality and maintain full compatibility.
> The kig save files will have an extra object (the segment AB), that during
> runtime will be present as an "internal" object.
>
> This is *exactly* the way that now the "midpoint" is created (misc/specialconstructors.cc
> and misc/builtin_stuff.cc).

This is the final behavior we will have.

> Of course there can be different points of view about what actions should/should not
> be implemented, and I am not contrary "by principle" to the new "perpendicular
> bisector" action (it would be better to speak of "Type" instead of action),
> however I would be very careful about doing something that forces the user to change
> the way he/she is accustomed to act in order to create some object.

That is what this patch was about: not changing the way to create a
segment axis with respect to the old segment-axis type.

> On the same line of though: it is *essential* that support for the segment axis
> property is not removed, otherwise kig would not be able to load old
> saved files.

This is correct and I still have to take a look at old file supports
after this patch, I'll look into it today.

David E. Narvaez