Re: [eigen] RotationBase times DiagonalMatrix

[Christoph Hertzberg <chtz@xxxxxxxxxxxxxxxxxxxxxxxx>]

On 26.09.2011 09:05, Hauke Heibel wrote:
> On Sat, Sep 24, 2011 at 4:47 PM, Christoph Hertzberg
> <chtz@xxxxxxxxxxxxxxxxxxxxxxxx>  wrote:
> > Maybe introducing a
> >
> >   template<class Derived>
> >   class TransformBase;
> >
> > is the solution. This would describe all Transformations -- affine or pure
> > linear.
>
> Probably the optimal solution. It just takes some time to implement
> such a change.

I guess so, too. And I currently don't have an urgent need for this, so 
don't count on me. Furthermore, I'm still not to keen working within 
internals of Eigen ...

> > If then someone does:
> >
> >   Transform a = Translation(...);
> >
> > he'll get a performance/memory penalty, but that's exactly the same for
> >
> >   Matrix<..>  m = Diagonal<...>(...);
>
> We would already have this scenario, when we removed the explicit
> keywords, right?

Yes, I guess that part would already work. What would not work is 
efficiently running functions such as these:

  template<class Derived>
  void foo(const TransformBase<Derived> &bar);

But this would run (even with conversion/memory overhead):

  void foo(const Transform &bar);


Christoph



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Dipl.-Inf. Christoph Hertzberg
Cartesium 0.051
Universität Bremen
Enrique-Schmidt-Straße 5
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