Issue 124060 - gradient gets white lines in metafile
Summary: gradient gets white lines in metafile
Status: CLOSED DUPLICATE of issue 93417
Alias: None
Product: Draw
Classification: Application
Component: viewing (show other issues)
Version: 4.1.0-dev
Hardware: All All
: P3 Normal (vote)
Target Milestone: ---
Assignee: Armin Le Grand
QA Contact:
URL:
Keywords:
Depends on:
Blocks:
 
Reported: 2014-01-19 23:58 UTC by Regina Henschel
Modified: 2017-05-20 09:59 UTC (History)
3 users (show)

See Also:
Issue Type: DEFECT
Latest Confirmation in: 4.1.0-dev
Developer Difficulty: ---

Attachments
Gradients original, metafile and bitmap (19.31 KB, application/vnd.sun.xml.impress)
2014-01-19 23:58 UTC, Regina Henschel 		no flags Details
slide show screenshot (25.17 KB, image/png)
2014-01-20 21:22 UTC, Edwin Sharp 		no flags Details
pdf screenshot (143.04 KB, image/png)
2014-01-20 21:23 UTC, Edwin Sharp 		no flags Details
Add an attachment (proposed patch, testcase, etc.)

Note You need to log in before you can comment on or make changes to this issue.
Description Regina Henschel 2014-01-19 23:58:08 UTC 
Created attachment 82320 [details]
Gradients original, metafile and bitmap

Open the attached file. Show it in presentation mode. Notice the white lines, especially in 16 steps.

Export the file to pdf. Notice the white lines in the exported pdf. How many lines are shown, depends on the zoom level in the pdf reader.
Comment 1 Edwin Sharp 2014-01-20 21:21:48 UTC 
Confirmed with
AOO410m1(Build:9750)  -  Rev. 1557669
2014-01-14_04:11:13 - Rev. 1557927
Debian
Comment 2 Edwin Sharp 2014-01-20 21:22:49 UTC 
Created attachment 82323 [details]
slide show screenshot
Comment 3 Edwin Sharp 2014-01-20 21:23:20 UTC 
Created attachment 82324 [details]
pdf screenshot
Comment 4 Armin Le Grand 2014-01-23 15:28:28 UTC 
It's not white lines, but anti-aliasing gaps. These happen when the format the user/exporter is based on uses Metafiles, but without using the "enhanced (hacked)' data included there e.g. for gradients. If this data is not used but the original Metafile data, it contains a pretty wild (from nowadays view) combination of X-ORed paints of polygons that was used in former days to render that gradients. When that X-ORed paints get executed 1:1 they generate that errors since that painitg technique of a gradient is of course not capable of AA.
With PDF it's similar; the adobe reader is bad with blending AAed stacked polygons above each other; the representation in the PDF is in principle correct (AFAIK).
Grepping, this needs work in the future. Best would be to change the exporters to primitive renderers, though...
Comment 5 Armin Le Grand 2014-03-27 14:20:05 UTC 
Same effect as already described in #93417#, setting to duplicate

*** This issue has been marked as a duplicate of issue 93417 ***