[kde-edu]: Re: Kig exporters: fix for rational bezier curves

[Maurizio Paolini]

It seems that we are now migrating kdeedu to git, and no svn commits
are allowed.

We must wait some time before committing patches.

Concerning the "ImpVisitor" object, I must confess that I have no
idea of their use and how they work.  If there is someone that can
answer Raoul, he is welcome!

Maurizio

On Wed, Mar 30, 2011 at 05:57:46PM +0200, Raoul wrote:
> Hi,
> 
> 
> In a recent mail I wrote:
> 
> > > And the rational bezier cuves do crash Kig when exporting
> > > to PSTricks, pgf/Tikz and Asy. But we can export to images
> > > and svg.
> 
> Today I debugged this and found what I think is the reason.
> Although I'm no expert on such things it seems to me the cause
> is an endless call loop in the following two code parts:
> 
> bezier_imp.cc:502:
> 
> void RationalBezierImp::visit( ObjectImpVisitor* vtor ) const
> {
>   vtor->visit( this );
> }
> 
> And object_imp.cc:83
> 
> void ObjectImpVisitor::visit( const ObjectImp* imp )
> {
>   imp->visit( this );
> }
> 
> The generic visit( const ObjectImp* imp ) is called because we
> have no specialization for RationalBezierImp Objects. I don't
> know why the generic function should call again imp->visit( this ) ...?
> 
> If I add this specialized function the issue is fixed. The patch
> attached does this and overwrites the function for Asy/TikZ and PS
> exporters. Thus we can now export rational bezier curves :-)
> 
> However the issue of course remains for other object types
> where there is no suitable visit function in the visitor.
> (I did not check if there are any more issues.)
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