Re: [Discuss-gnuradio] Extending a GNU Radio block with use of inheritance

[Piotr Krysik]

W dniu 02.06.2016 o 11:28, Andrej Rode pisze:
> Hello Piotr,
>
>> If I can inherit from *_impl classes - are you able to present how to do
>> it? *_impl.h headers are not installed together with GNU Radio so I'm
>> not able include them.
> If you want to modify basic blocks shipped with GNU Radio you should
> install GNU radio sources. Depending on your distribution you could use
> PyBOMBS to get reproducible GNU Radio builds with your modifications.
>
>  And this is just a start - then I don't know how
>> prepare CMake files so derived class is linked correctly, and how to
>> prepare SWIG input file. If you are able to spare some time to describe
>> it I would greatly appreciate that.
> I don't know of your current experience with GNU Radio but it sounds
> like you did not play around a lot with GNU Radio already.
> For projects not relevant for the main GNU Radio tree there exists the
> concept of Out-Of-Tree modules (OOT-Modules). With the tool gr_modtool
> it is quite easy to get started with your own module/blocks.
>
> I myself did not modify/create inherited blocks from already existing
> blocks in GNU Radio. The $(class)_impl method was just a suggestion to
> get a hand on the general_work function of the class. Maybe someone else
> will also comment on this issue on the mailing lists. As GNU Radio is
> Free Software you can and should take a look at the sources yourself :).
>
> If you are new to GNU Radio best take a look at the Tutorials [0]. For
> creating own modules especially the OOT-Guide is very useful [1].
>
> Best Regards,
> Andrej
>
> [0] http://gnuradio.org/redmine/projects/gnuradio/wiki/Tutorials
> [1] http://gnuradio.org/redmine/projects/gnuradio/wiki/OutOfTreeModules
>
>
>
Hi Andrej and all,

I have some experience with OOT modules - I've developed two OOT
projects (gr-gsm and Multi-RTL). And this is part of the problem - I've
played a bit with GNU Radio, I'm familiar with portions of GNU Radio's
source code, but I still don't know how to use inheritance to extend
existing blocks (something that in a lot of cases would make perfect sense).

I can modify GNU Radio source - but this way I will create a new version
of GNU Radio (specific for needs of my project) that users of my
projects will have to install. In comparison with that copying the
signal processing block's code to my project in order to add few lines
is a lot better option (in terms of amount of code that need to be
maintained, distributed and installed). And the point is to make things
easier not harder for everyone. If a GNU Radio's gurus tell me that
copying the source code is the best option in this situation and I that
shouldn't try to do that with use of inheritance, I'll be able to live
with that answer :).

P.S. please respond also to the mailing-list so others can benefit from
your responses.

Best Regards,
Piotr Krysik