Bug 688605 - A shading displaced when rendering a re-distilled Altona-Testsuite_p2_S_x3.pdf
Summary: A shading displaced when rendering a re-distilled Altona-Testsuite_p2_S_x3.pdf
Status: RESOLVED FIXED
Alias: None
Product: Ghostscript
Classification: Unclassified
Component: Graphics Library (show other bugs)
Version: master
Hardware: PC Linux
: P4 normal
Assignee: Robin Watts
URL:
Keywords: bountiable
Depends on:
Blocks:
 
Reported: 2006-03-20 11:38 UTC by leonardo
Modified: 2016-12-08 06:35 UTC (History)
3 users (show)

See Also:
Customer:
Word Size: ---

Attachments
out6665.pdf (3.91 MB, application/pdf)
2006-03-20 11:42 UTC, leonardo 		Details
decompr-out6665-.pdf (106.03 KB, application/pdf)
2006-03-20 23:54 UTC, leonardo 		Details
cur1.ppm.zip (14.50 KB, application/octet-stream)
2006-03-21 01:29 UTC, leonardo 		Details
Add an attachment (proposed patch, testcase, etc.)

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Description leonardo 2006-03-20 11:38:25 UTC 
A vertical line appears over the shading when executing :

gs6665/bin/gs -Igs6665/lib:/home/regression/fonts/ -dBATCH -dNOPAUSE -
sDEVICE=pdfwrite -sOutputFile=out6665.pdf -c false 0 startjob pop -f - 
<~regression/comparefiles/"STEUER-RollingMesh 3(Final).ai"
gs6665/bin/gs -Igs6665/lib:/home/regression/fonts/ -r72 -dBATCH -dNOPAUSE -
sDEVICE=ppmraw -sOutputFile=out6665.ppm out6665.pdf

Used Ghostscript revision 6665, debug build and runs on peeves, Linux.
Comment 1 leonardo 2006-03-20 11:42:07 UTC 
Created attachment 2114 [details]
out6665.pdf

Attaching a copy of the PDF file.
This bug looks similar to 688407, but actually it's another problem. That one
was about pdfwrite, this one is about raster devices.
Comment 2 leonardo 2006-03-20 11:44:25 UTC 
Oops, the bug description lists a wrong test case. It should be Altona-
Testsuite_p2_S_x3.pdf instead "STEUER-RollingMesh 3(Final).ai".
Comment 3 leonardo 2006-03-20 23:54:09 UTC 
Created attachment 2115 [details]
decompr-out6665-.pdf

A simplified test file : unrelated graphics removed, unrelated clip path
removed, colors changed for a better visibility.
Comment 4 leonardo 2006-03-21 01:25:52 UTC 
The verticall line appears due to 0.5 .setfilladjust in gs_init.ps for small 
resolutions. The left half of the circle is painted with clippig [10734.1, 
11379.1) by X, and the right half is painted with the clipping [11379.1, 
12024.2). They round to [1073, 1138) and [137, 1203) device pixels. In same 
time, the right half is painted with filling a path, which covers [11379, 
11970) by X. The letter applies a quoter pixel fill_adjust, and then rounds to 
[1138, 1197) device pixels. Thus the right half doesn't paint the pixel x=1137. 
A better result would appear if fill_adjust is equal to 0.5 pixels.

This is another time when we detect an incorrect behavior with 
fill_adjust=0.5 . I think that fill_adjust=0.25 must apply to 'stroke' only, or 
stroking must implement a smarter logic, when fill_adjust is accounted in the 
line width. 'fill' operators must always use fill_adjust=0.5 .

Passing the bug to Ray, who defined the fill_adjust logic. Please note a 
similar bug 688407 is important for a customer.
Comment 5 leonardo 2006-03-21 01:29:30 UTC 
Created attachment 2116 [details]
cur1.ppm.zip

The raster generated with -r72. A vertical line appears across the shading.
Comment 6 Michael Vrhel 2011-06-11 23:50:24 UTC 
A shading with line problem.  Likely similar to the shading line problem that Robin was just working on so assigning to him.
Comment 7 Shailesh Mistry 2011-07-18 21:50:12 UTC 
Bug still reproducible in Ghostscript 9.03
Comment 8 Alex Cherepanov 2016-07-14 19:23:18 UTC 
This is fixed in v. 9.09 and higher. The bug can be closed.
Comment 9 Ken Sharp 2016-12-08 06:35:30 UTC 
I agree with Alex's comment #8, and so I'm closing this bug.