Printing from Virtuoso (or printing GDSII)

I have a problem creating good printouts from Virtuso's layouts for
documentation porposes.

I want vector graphics output OR high resolution bitmap. The problem
with Cadence is that their printing service produces a horrible
mixture of both.
If you have one of the following outputs set up:

- postscript (1,2): you get the outlines of polygons as a vector
graphic and the fill patterns as low-res bitmaps; unfortunately the
fill patterns are not clipped to their corresponding polygons but
merged with all layers and cut in ‘larger squares' afterwards. With
the :residentfonts: option text is preserved as text, but each letter
as a separate object, so you cannot change the size or shape of text
afterwards.
- hpgl: you get only the polygon outlines, no fill patterns;
unfortunately shapes are merged, clipped and stacking orders do no
longer correspond to the drawing layers.

The best way seems to be to export a GDSII stream and use a third
party utility.


So far I tried:
__________
sfviewer 3.5 http://www.nathaniyer.com
Does not preserve colour during export or clipboard-copy. No custom
fill patterns.
__________
GDSII Viewer 1.58b ()
Works fine so far, layer stacking order is messed up though. This
could be fixed in Adobe Illustrator (or similar) afterwards, but is
time consuming.
Perhaps I create a script for that…
I have no URL, but I can send you that program (+source) on request.
__________
SoC GDS Seduction
http://www.dolphin.fr/medal/socgds/socgds_free_overview.html
Does not allow you to print or export graphics.




Do you have any suggestions what else I can try?

 

This is an unfortunate aspect of how display stipples are defined. I,
too, have been less than pleased with the resulting output.

I can think of a number of fixes, but none are that simple:

1. Allow the display data to define both a bitmap and a
Postscript-defined pattern. Then your fill patterns are defined in the
ideal formats for both screen and paper. Downside: requires more work
for the user.

2. Allow the user to specify how much the bitmap is bloated. Downside:
very hard to make this look right.

I am seeing some oddities with the way we draw polygons and conics, but
the resulting output looks correct. Are you seeing the same?

At any rate, we probably should be clipping the polygons. I'll see if I
can find out why we're not.

Hm... this I'm not seeing. I put a label, "This is a label", on my
layout; I see the following Postscript:

1 rfta save 0 /Courier findfont
140 90 0 rfsc
(This is a label) rft

(Just to make sure... you've spelled the option as :residentFonts: ?)

Can you describe how to make a small testcase which exercises this?

Unfortunately, I have no way of testing HPGL output here in Pittsburgh,
so I can't comment on this.

Another route (which I might try out this afternoon) is to write a SKILL
script which generates Postscript directly from the objects on the
layout. It's about a week's worth of effort if you're a SKILL and
Postscript expert, much longer otherwise.

Anyway, I will ping the CAT folks (who are in charge of plotting
services) on these issues.

Thanks,
Dave

 

Dave,

I would like to generate EMF files from (simple) schematics or waveforms. How could I do this in skill ? (I hope it would be cleaner than from eps to emf).

 

Hi Dave,
thanks for the detailed reply.

How exactly would I do this? The documentation of the display resource
file shows only how to create bitmap patterns.
Could you please give me an example how to define a postscript fill
pattern?

The polygons are correct. But if plot HPGL or remove the fill patterns
from postscript afterwards it is very time consuming to fill these
polygons with nice patterns (in Illustrator).

I didn't actually look into the ps file, I just tried to change the
text in Illustrator which failed to work. I will have a look at that
issue again and report back here. Maybe I misspelled the
resident-fonts option.



Writing a SKILL tool to export to postscript directly would be nice
(and much appreciated by many Cadence customers), but I do not have
any experience with SKILL or postscript.



The PNG-Output Roger Light suggested works actually quite good. I
still need to fine-tune the printing resolution and plot-scale (which
both have an effect on pattern-density)

regards,
Manuel

 

Hm. Not easily. The problem is that EMF (Windows Enhanced Metafiles)
is a binary format, and SKILL generally does not handle binary strings
well (specifically, it won't pass NUL characters through).

What platform are you running on? Let me see if I can't get something
written this weekend. There have been more than a few times when I've
needed to get a picture of a schematic into a paper, and it's always
been a bit hairy.

 

Ah, sorry... I was speculating on how we could fix it (inside Cadence).
There's no way to do this (as of yet).

Ok, now I understand the issue here. Basically, because we're not
outputting something more standard, other tools are having issues
reading the Postscript.

It's possible that our resident font code is drawing each character
individually in order to make the output text roughly the same size as
the DFII plotter fonts.

Heh, ok, I hear you guys loud and clear.

 

I wrote a research version of a GDSII viewer that has image capture
capabilities at:
http://cuervo.eecs.berkeley.edu

Click on the "New GDS Viewer by Frank Gennari".

There are a number of know bugs which may or may not be fixed eventually,
but it should be able to generate JPEG, RAW, and Windows BMP images of
arbitrary resolution with stipple patterns, even for large GDSII files.

Frank

 

(warning: do not read further unless your immune system can withstand
repeated evocations of "microsoft" and "windows" )

I can use HPUX/HPPA, various linuces, various windows, solaris 8. But
only monday. At home I can use windows XPpro and linux. Concurrently,
thanks to vmware.

I suppose you want to use a windows print queue, some service or RPC,
so that the EMF binary is actually generated by a windows machine. That
would be a fine solution too. You can find on MSDN how to adress the EMF
API, for instance this
http://msdn.microsoft.com/library/default.asp?url=/library/en-us/gdi/wingdistart_9ezp.asp

 

Frank,

I can see you are using openGL in a less (ahem...)blunt way than me. I
was just making C functions call from the SREFs, and that is quite
annoying if the end-user needs a compiler to just run the gds viewer.
How did you take advantage of the structures in your viewer ? Using
openGL's display lists ?
(BTW: are you going to put yet what can be opened on sourceforge or
savannah ?)

 

Dave,
I just had a look in the source of openoffice (v 1.1 ) and found an
EMF writer class under ./svtools/source/filter.vcl/wmf/ and a GDI
implementations (if you want to get rid of the need for a windows
machine) under ./vcl/source/gdi/

It is a shame there is no documented way to call external C functions
from skill. Could that EMF writer class be turned into some kind of
interpreter daemon that waits for skill to send GDI-like commands to it ?

 

Actually, I would prefer to write out the file directly. It's a bit
tricky to talk to machines running different operating systems at N
different sites which all have different IT policies...

I did find the EMF format documentation, and will take a look at the
OpenOffice source you pointed to. Thanks.

Dave

 

Right, the C-SKILL interface is internal only -- it would, at present,
be a maintenance nightmare if arbitrary C libraries were allowed to hook
in. This is one area I and a number of others in CIC are keenly
interested in fixing. It will take some time, though.

Unfortunately, there's no easy way to hook arbitrary components together
on Unix platforms (ala Windows COM). We are aware of XPCOM, and did
have an internal project to replicate COM (in the pre-XPCOM days), but
those efforts have not met with much success/enthusiasm/traction/... .
As much as I personally dislike Java, this may be a good application for it.

 

The layout software package I offer has a printing option. The
output can be a PNM file. PNM's can be easily
translated to jpeg if desired. The PNM file is a pure
fairly high resolution bitmap. (about 3k pixels in each
direction). If you'd like to give it a try let me
know & I'll set you up with an eval key.

Mike Stabenfeldt
http://www.stabie-soft.com

 

My layout viewer is quite complex. It loads the GDSII file into a compressed
hierarchical database and traverses the hierarchy to find visible cells to
display. The shapes are all drawn with glVertex calls and consist of
combinations of points, lines, quads, triangles, triangle strips, and
triangle fans. The polygons are decomposed into my internal display list
format, where level-of-detail algorithms are used to render the primitive
shapes. The screenshot images are generated directly from tiled frame buffer
images, which are produced by OpenGL typically through some hardware support
from the video card.

The source code for the research version is currently available from my
research group to SRC companies only (since my research was sponsored by
SRC), and by next summer will be available to non-SRC companies as well. My
company is currently working on an improved version of this code, but it may
not be officially released. The source code of the new viewer is part of a
commercial product that is under development and therefore cannot be
released.

Frank

 

Thanks for the background info.

 

Hi Dave,
did you mannage to get write skill code for that issue?

regards,
Manuel

 

With the :residentfonts: option text is preserved as text, but each
letter

If you use our ps2vector software to batch convert such PS output to
EPS or another vector format (e.g. SVG, WMF, CGM, MIF), it will
automatically merge individual characters into words and words into
one-line text strings in the output - so you can more easily edit the
text and its attributes, while saving filesize. Users of Cadence and
other CAD/EDA systems have used it since 1995 to bring graphics output
into their documentation and publishing systems in scalable and
editable vector formats. Available on Windows, Linux and UNIX
platforms.

You're welcome to send me a sample (E)PS file to give it a try.

Jeroen Dekker

 

I want vector graphics output OR high resolution bitmap. The problem

We also have a ps2bitmap module to render the PS file to a TIFF, GIF or
JPEG raster image file at any dpi resolution or color depth.
Jeroen Dekker

 

I would like to generate EMF files from (simple) schematics or

Generating EMF straight from GDI is obviously only possible on Windows.

Have you tried our ps2vector software to convert EPS to EMF? Some
pretty big electronics manufacturers are pretty happy with it, and
chose us over open-source alternatives. Curves stay curves, text stays
text, line styles are preserved, images are preserved, cropping is
preserved. Since it takes (E)PS as input, it can be used in conjunction
with Cadence on any platform.

Something ps2vector can do automatically during conversion. It does
Neat Tricks, developed for users like y'all.

Jeroen Dekker