Bug 687677

Summary: stroking: an 'arct' segment isn't painted
Product: Ghostscript Reporter: Igor Melichev <igor.melichev>
Component: Graphics LibraryAssignee: Robin Watts <robin.watts>
Status: CONFIRMED ---    
Severity: minor CC: missoumozil, shailesh.mistry, sphinx.pinastri
Priority: P3 Keywords: bountiable
Version: master   
Hardware: PC   
OS: Windows XP   
Customer: Word Size: ---
Attachments: 014-01.pdf
687677-tiffs.zip

Description Igor Melichev 2004-09-15 01:26:15 UTC 
A vertical line dissappears in the box 014-01 when rendering re-discrtilled 014-
01.ps with HEAD. Adobe paints it. I guess the 'arct' may be not conforming in 
the PDF interpreter. Same with 015-01.ps .
Comment 1 Igor Melichev 2004-09-15 01:28:49 UTC 
Created attachment 896 [details]
014-01.pdf

The test file generated with 

gswin32c.exe -dNOPAUSE -dNOOUTERSAVE -dBATCH -sDEVICE=pdfwrite
-sOutputFile=014-01.pdf -c false 0 startjob pop -f - <comparefiles/014-01.ps
Comment 2 Igor Melichev 2004-09-15 01:29:40 UTC 
Reported by Julia as a regression from Dec 09, 2003.
Reproduced by Igor with today's CVS HEAD
Comment 3 Igor Melichev 2004-09-15 01:32:09 UTC 
To reproduce the problem :

gswin32c.exe-r300 -dNOPAUSE  -sDEVICE=ppmraw -sOutputFile=z:\cur.ppm 014-
01.pdf -c quit
Comment 4 Ray Johnston 2004-09-15 10:19:40 UTC 
This shows different drop outs at different resolutions.

At -r120 the bottom part of a curve is missing.

At -r72 a vertical segment is missing.
Comment 5 Ray Johnston 2004-09-15 10:34:21 UTC 
At 120 dpi, doing 0.5 .setfilladjust makes the horizontal dropout on the
curve disappear:
    gs -r120 -c 0.5 .setfilladjust 014-01.ps

The vertical lines missing at 72 dpi do not appear to be affected
by increasing the .setfilladjust setting. Most likely this is a
result of fill coordinates in those vertical 'lines' being rounded
to a 0 width fill (same X coordinates going up and down). Raph feels
that this is an undefined area of the Adobe PS spec.

One thing that is noted is that we should set the fill adjust to
0.5 if we are using GraphicsAlphaBits > 1 so that anti-aliasing
will work better. This can be seen at 120 dpi, although the
anti-aliased rendering still shows a dropout on the curve (due
to a low gray intensity being rounded down rather than up ?)
Comment 6 Ken Sharp 2009-10-13 09:43:18 UTC 
Created attachment 5478 [details]
687677-tiffs.zip

Tiff files from Acrobat at 72, 100 and 120 dpi.
Comment 7 Henry Stiles 2009-11-19 07:50:28 UTC 
Reassigning path and fill problems to Robin Watts.
Comment 8 Robin Watts 2010-01-28 17:21:04 UTC 
Reassigning to new email address.
Comment 9 Shailesh Mistry 2011-07-11 20:02:47 UTC 
Bug still reproducible in Ghostscript 9.03
Comment 12 Peter Cherepanov 2021-01-02 03:03:17 UTC 
The problem is still in the current master branch.