[PEDA] Octagonal Pads

[Geoff Harland]

Dennis Saputelli wrote:
<snip>
> Geoff Harland wrote:
> > Or have I "grabbed the wrong end of the stick" in this instance, and
> > you actually want just two of the four corners to be rounded instead?
>
> yes this is what i had wanted
>
> these sorts of shapes can be very handy at times, chokes, buttons, dual
> footprint compromises that customers always demand
>
> ideally i would like to be able to define a completely arbitrary pad
> shape, e.g. a polygon with differing radiused corners
>
> failing that then the current rounded rectangle but with 4 (or 2)
> settable corner radii
>
> failing both of those then also acceptable would be piling up a bunch of
> junk (tracks, fills, regions, other pads) BUT without the current
> nuisance of having to update free primitives all the time

I thought that there had been improvements in updating the Net properties of
(non-pad) primitives in relatively recent times. (Or was that an instance of
an "overly optimistic" item within the release notes provided for one of the
SPs released for AD6?)

And would defining an union of the primitives of interest be helpful at all
in such circumstances? (Originally each union consisted of a set of
components, but I gather that at some stage the concept was extended to
enable users to "group" *any* set of objects.)

> these primitives when part of a component and when touching a pad and
> when on an electrical layer should simply become children of the pad,
> sort of like a nested sub component and any child pads should lose most
> of their electrical properties such as designator so that that ambiguity
> would also be solved
> solder mask and paste could be offered as a calculation of the boundary
> of the finished composite object (sort of a 'SUPER-PAD') or simply drawn
> or pasted from the conglomerate mess

I am pretty sure that P-CAD provides the ability for users to define shapes
of their own choosing for each layer of a pad (including Paste Mask and
Solder Mask layers, and P-CAD's equivalent of Power Plane layers), and has
done so for a number of major versions; there is also a "default" option
available for the Solder Mask layers in which the details on those layers
are derived from the details on the appropriate external copper layer in
conjunction with a "Solder Mask Expansion" setting. (I'm not sure whether a
similar feature is also provided for the Paste Mask layers, but perhaps
there is.)

I don't know whether that functionality will ever be provided within AD as
well, but if P-CAD users are not going to lose any of the functionality
which is currently provided to them, it would need to be implemented at some
stage (though perhaps in a following major version of AD, rather than within
AD6).

> DXF is high on my list to fix

My recollection is that DXF files have been an issue for some time. I would
be prepared to make *some* allowances for issues involving DXF files being
*imported* (as there could be issues involving how to interpret the data in
some circumstances), but there should still be clear documentation as to
what requirements are necessary for DXF files to be successfully imported,
and those requirements should also be fully "realistic" (as far as other
applications actually generating such files in the first instance are
concerned). OTOH, there *shouldn't* be *any* issues when it comes to
*exporting* DXF files instead (as I am unaware of any aspects of AD which
could not be "accommodated" by the specifications which have been released
for DXF files).

For the time being, and as you possibly know, workarounds could consist of
hanging on to major versions of AD/Protel which preceded AD6 (such as AD
2004, DXP, Protel 99 SE, Protel 98, etc), as different versions handled DXF
files in different ways, and also keeping your eyes open for applications or
utilities which convert DXF files into other types of files, such as Gerber
files (as one example).

Regards,
Geoff Harland.