Rotation support (was: Re: DIA function)

[Hans Breuer <hans breuer org>]

Am 06.03.2015 um 09:57 schrieb T.Tetzner:
> Hello to all,
>
> I work for several weeks with DIA and I pretty much love it. Mainly I
> create P&ID s. There is only one feature I really miss: The possibility to
> turn/spin elements and text in angle you need.
Object rotation is a long-time requested feature which made some progress 
in recent years, see:
https://git.gnome.org/browse/dia/log/?qt=grep&q=\[transform\]
for the current capabilities.

One of the implemented features is indeed a rotation angle for the 
'Standard - Text' element. But general rotation of all elements still has 
significant constraints, e.g.:
 - objects in rotated groups loose their connectability
 - to preserve connectability (and meaning of connection point directions
   used for autorouting) objects get an angle property on a case-by-case
   basis. Currently only "Standard - *" objects plus Group have it.
 - only few renderers support native rotation/transformation. For others
   rotated text is automatically converted to outlines with the help of
   (Pango)Cairo
 - text rotation with direct Pango/Freetype is not implemented (yet?)
   To get the best working version use './configure --disable-freetype'.

> That means if I construct a
> new component I have to create a horizontal and vertical version to my own
> database.
Are you asking for something like "Flip Diagonal" in the context menu of 
shapes (similar to the exisiting Flip Horizontal and Flip Vertical)?

> Maybe it is possible to include that feature.
Patches accepted :-)

> In general I love your program. I will donate a amount via PayPal to you.
> If you want I could send to you an example of my work with DIA.
Interesting diagrams used to illustrate the issue at hand are always 
welcome. Of course they should not be confidential, because this is a 
public mailing list.

Happy diagramming,
        Hans

-------- Hans "at" Breuer "dot" Org -----------
Tell me what you need, and I'll tell you how to
get along without it.                -- Dilbert