Re: On the connectors examples - is this intended in the 'use with symbols' example?

Hello world ;-)

Smailus, Thomas O wrote:
>  
> 
> Not sure where I should have posted this, but as it piqued my interest 
> in the HTML / SVG WG joint meeting...
> 
>  
> 
> In http://tavmjong.free.fr/SVG/CONNECTORS/index.xhtml
> 
> There is an example of problems with symbols, and Figure 5 – use with 
> symbols.
> 
>  
> 
> The use of circular, which appear to be associated with the in and out 
> points on the AND gates. 
> 
>  
> 
> Circles mean something in logic gate diagrams – negating the signal.  So 
> an AND gate may or may not have a negated input and/or output.
> 
>  
> 
> How would this work in a logic diagram where we have an AND gate where 
> we specify a gate (do we need to have the combinatorial explosion of 
> gates defined when using circle or non-circle terminators)?

If you are interested in the practical usecase of "combinational and 
sequential circuits" as an example for connectors in SVG, you might have 
a look at my "SVG connector proposal" page. I just had a few minutes 
time to provide two simple circuits as examples, using a real and 
working "SVG reference point implementation". Just have a look at
http://jroethig.de/geolog/connector.html#l2demcircuits
The XML files are the relevant files using an enhanced SVG syntax 
(enhanced by my "reference point proposal" syntax). These files are 
transformed via XSLT to standard SVG syntax (the SVG files which are 
also provided for reference), but with real coordinates instead of 
reference points. The unusual attributes with xmlns:jr in the standard 
SVG files are due to the fact that the implementation needs also some 
JavaScript part which still relies on the refpoint names which are 
additionally given in those attributes.

Referring to your specific question: The "circles" (or negations) are 
done via marker-start and marker-end for the "connectors", although this 
might also be achieved by a special symbol positioned at the start or 
end of that connector, instead (basically just a case of personal 
taste). But the negations would most probably not be achieved as a part 
of the symbol for the specific gate.

And I might add, once again, that my "connector proposal" is not really 
a proposal for connectors in SVG, but for defining just "reference 
points", which might be used instead of any coordinate pair in any SVG 
tag using such a coordinate pair. Thus, the connectors might be formed 
by whatever element which is able to connect two and more points, i.e. 
line, polyline, polygon, path, ..., and the reference points might even 
be used to position any other element (e.g. text, circle, ...).

Juergen Roethig

Received on Thursday, 6 November 2014 13:03:43 UTC