kicad-developers team mailing list archive

[Lorenzo Marcantonio <l.marcantonio@xxxxxxxxxxxx>]

On Fri, Apr 19, 2013 at 09:06:39AM -0400, Wayne Stambaugh wrote:
> comments about indices is correct.  Using an ordinal number does not
> guarantee layer compatibility when we finally get around to adding
> more layers. They are also not readable.  What is a layer 0, 1, 2,
> 3...N?  You would always have to refer back to the layer table to
> know which layer the ordinal number is mapped to if they were used
> define layers in the rest of the file.  The only good thing about
> ordinal numbers in this case is they cannot be translated.

OK, I got it. It's a 'transitional phase', and the layer number are
more or less scheduled to disappear (or be deprecated), at least from
the external files. I am not too happy with numbered layer but they
could do *inside* of pcbnew. In the file format I agree they are only
a nuisance.

> That being said, I do believe that providing users a way to define
> their own layer names that can be translated is a good thing.  It's
> just that they cannot be used in the file layer definitions or any
> of the layer manipulation code.  They can only be mapped to the
> standard layer names and only be used for UI purposes.  I'm guessing
> that adding a 4th entry to the layer definition in the file would do
> the trick.  However, I am in agreement with Dick that we should get
> the footprint library table implemented so that both the board and
> footprint file formats are stable then consider how we want to add
> user defined layer names.  I working on it as fast as I can given my
> time constraints.

So it would be like my second scenario. Perfectly fine with that, I have
no hurry. Internal names are the layer key and user names are for user
convenience, everybody wins. In the end LAYER_NUM could be even be some
kind of interned string...

The thing I was worried about was the complete inflexibility of Dick
about layer naming. If it meant the 'internal and file format ones'
I agree with him. In this case I think that keeping the internal names
even for the copper layers (in the file) would be the better thing to do
(since there is anyway a 'user name' field available)

Thanks for the explanation (and a little bit of roadmap).

-- 
Lorenzo Marcantonio
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