bugGNU Octave - Bugs: bug #42580, contour shows interconnections


bug #42580: contour shows interconnections

Submitted by:  Andreas Weber <andy1978>
Submitted on:  Wed 18 Jun 2014 04:30:10 PM UTC  
Category: Plotting with OpenGLSeverity: 3 - Normal
Priority: 5 - NormalItem Group: None
Status: Works For MeAssigned to: None
Originator Name: Open/Closed: Open
Release: devOperating System: GNU/Linux

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Thu 19 Jun 2014 03:35:28 PM UTC, comment #4:

There are several possibilities. One is that this is related to bug #39370 (duplicate points added to start/end of contour level). More likely, it is due to differences in the OpenGL version or in to the implementation by AMD.

I am running OpenGL 2.1 on Intel hardware and don't see the problem.

Rik <rik5>
Project Administrator
Thu 19 Jun 2014 09:27:28 AM UTC, comment #3:

Yes, the machine with AMD GPU (at work) shows this issue too. Just tried at home with nvidia GPU and the problem doesn't occur.

However, even with nvidia GPU there are strange effects when moving the plot window outside the screen. While moving the windows back to center, the part that was outside the screen gets disturbed. If I stop moving the window the plot is redrawn and looks normal again.

Stefan Mahr <dac922>
Thu 19 Jun 2014 06:19:46 AM UTC, comment #2:

I was able to reproduce this on 2 different machines (but both AMD GPU)

dac922 was also able to reproduce the problem on his system.

Andreas Weber <andy1978>
Project Member
Thu 19 Jun 2014 01:59:30 AM UTC, comment #1:

This works for me, i.e., no problematical lines across the contour. Maybe try running 'run-octave -f' to make sure you are running without any initialization files. Also, what version of OpenGL are you using?

Rik <rik5>
Project Administrator
Wed 18 Jun 2014 04:30:10 PM UTC, original submission:

hg id 5eca3080c7cd

and move mouse over plot window or move the window to trigger the fl_window:draw routine and thus opengl_renderer::draw_patch. I guess the error happens here but I haven't enough time yet to debug it further. This also happens with graphics_toolkit qt when you move the window (moving the cursor over the figure doesn't call the redraw routine in qt)

You will see additional secants drawn in the color of the current patch. (attached some screenshots)

Andreas Weber <andy1978>
Project Member


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Attach File(s):

Attached Files
file #31576:  sec1.png added by andy1978 (17kB - image/png)
file #31577:  sec3.png added by andy1978 (16kB - image/png)
file #31578:  sec5.png added by andy1978 (16kB - image/png)
file #31579:  sec6.png added by andy1978 (16kB - image/png)


Depends on the following items: None found

Items that depend on this one: None found


Carbon-Copy List
  • -unavailable- added by dac922 (Posted a comment)
  • -unavailable- added by rik5 (Posted a comment)
  • -unavailable- added by andy1978 (Submitted the item)

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    Follow 5 latest changes.

    Date Changed By Updated Field Previous Value => Replaced By
    Thu 19 Jun 2014 01:59:41 AM UTCrik5StatusNone=>Works For Me
    Wed 18 Jun 2014 04:30:10 PM UTCandy1978Attached File-=>Added sec1.png, #31576
      Attached File-=>Added sec3.png, #31577
      Attached File-=>Added sec5.png, #31578
      Attached File-=>Added sec6.png, #31579

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