TechDraw drawing rendering as only gray window

Discussions about the development of the TechDraw workbench
mcdanlj
Posts: 5
Joined: Sun Dec 01, 2019 12:10 am

TechDraw drawing rendering as only gray window

Postby mcdanlj » Sun Dec 01, 2019 12:44 am

I have a model for which I have created a TechDraw drawing. I opened the file in FreeCAD to make a modification to the drawing, and it rendered only gray. I have been keeping versions of the file in git, so I reverted to older versions of the file, and it still renders only gray. However, two other FCStd files in the same directory, also with drawings, render fine.

I first experienced this with FreeCAD_0.18-16146-Linux-Conda_Py3Qt5_glibc2.12-x86_64.AppImage though it also reproduces on FreeCAD_0.18-16131-Linux-Conda_Py3Qt5_glibc2.12-x86_64.AppImage

I have searched the forum for others seeing this issue without finding it, though it's possible I'm just not thinking of the right words to search for.

Here's the file open:
model-view.png
model-view.png (262.7 KiB) Viewed 332 times


Here's what the gray document window looks like:
not-drawing-view.png
not-drawing-view.png (208.88 KiB) Viewed 332 times

More files:
  • QCTP-TopNut.FCStd is the file in question.
  • QCTP-TopNut.pdf is the most recent PDF export of the drawing.
  • QCTP-Handle.FCStd is another file created together, saved from the same FreeCAD session, that is not exhibiting this bug for me.
About FreeCAD:
OS: Fedora 30 (Thirty)
Word size of OS: 64-bit
Word size of FreeCAD: 64-bit
Version: 0.18.16146 (Git) AppImage
Build type: Release
Branch: (HEAD detached at 0.18.4)
Hash: 980bf9060e28555fecd9e3462f68ca74007b70f8
Python version: 3.6.7
Qt version: 5.6.2
Coin version: 4.0.0a
OCC version: 7.3.0
Locale: English/UnitedStates (en_US)

I have not updated FreeCAD and not updated any OS components since saving this file, though I tested whether an older version of FreeCAD reproduced the problem (it did).
Attachments
QCTP-Handle.FCStd
(28.93 KiB) Downloaded 6 times
QCTP-TopNut.pdf
(161.85 KiB) Downloaded 4 times
QCTP-TopNut.FCStd
(789.88 KiB) Downloaded 7 times
chrisb
Posts: 21376
Joined: Tue Mar 17, 2015 9:14 am

Re: TechDraw drawing rendering as only gray window

Postby chrisb » Sun Dec 01, 2019 6:49 am

It's no problem here, neither with 0.18.4 nor with 0.19. Is it possible that you see some horrendous zoom? Try zoom fit. You can try to reset the configuration with the button in the preferences. Another possibility is to delete your config files or to move them in case you want to restore them.
mcdanlj
Posts: 5
Joined: Sun Dec 01, 2019 12:10 am

Re: TechDraw drawing rendering as only gray window

Postby mcdanlj » Sun Dec 01, 2019 12:47 pm

Thanks for checking! It seemed unlikely that the information was actually lost, since older versions of the file also failed to load, and I had made changes to the drawing since.

After posting about the problem, I recreated the drawing and it is working fine. So I'm not in a hurry; I am more trying to get enough information to file a useful bug report. Right now it's in the "can't reproduce, not blocking my progress" state.
chrisb wrote:
Sun Dec 01, 2019 6:49 am
Is it possible that you see some horrendous zoom?
Zoom was indeed the first thing I expected, and "VF" was my first try to fix it.

I checked out the failing version of the file and the problem reproduces, and every item on the View → Zoom menu is grayed out. So it seems like it is failing to render the text drawing view at all. No console messages.
chrisb wrote:
Sun Dec 01, 2019 6:49 am
Another possibility is to delete your config files or to move them in case you want to restore them.
Temporarily renaming only user.cfg, only system.cfg, or both user.cfg and system.cfg together does not resolve the issue.
chrisb
Posts: 21376
Joined: Tue Mar 17, 2015 9:14 am

Re: TechDraw drawing rendering as only gray window

Postby chrisb » Sun Dec 01, 2019 12:51 pm

You may try with a current 0.19 version. Many things have been fixed, and it got a new Qt version.
mcdanlj
Posts: 5
Joined: Sun Dec 01, 2019 12:10 am

Re: TechDraw drawing rendering as only gray window

Postby mcdanlj » Sun Dec 01, 2019 7:11 pm

chrisb wrote:
Sun Dec 01, 2019 12:51 pm
You may try with a current 0.19 version. Many things have been fixed, and it got a new Qt version.
Downloaded and tried FreeCAD_0.19-18811-Linux-Conda_Py3Qt5_glibc2.12-x86_64.AppImage

Well, that's interesting!

Yes, it makes the drawing show. However, there are some artifacts:
  • The Vertical-A section is upside down
  • Several dimensions don't make sense any more, like a diameter of 0.000 and an angle of Inf. You can compare the screen shot image below to the PDF attached in the original post to see how it's different.
upside-down-and-infinite.png
upside-down-and-infinite.png (166.17 KiB) Viewed 276 times
Does that reproduce for you in 0.19? And does the drawing look the same in 0.18 and 0.19 for you?

If that difference persists, I'm happy to file it as a bug if that's useful. ☺
chrisb
Posts: 21376
Joined: Tue Mar 17, 2015 9:14 am

Re: TechDraw drawing rendering as only gray window

Postby chrisb » Sun Dec 01, 2019 9:27 pm

I moved this topic to TechDraw forum. Wandererfan has recently worked on the orientation of DetailViews, so this may be related.
vocx
Posts: 2811
Joined: Thu Oct 18, 2018 9:18 pm

Re: TechDraw drawing rendering as only gray window

Postby vocx » Mon Dec 02, 2019 12:00 am

mcdanlj wrote:
Sun Dec 01, 2019 7:11 pm
...
The Vertical-A section is upside down
The author of TechDraw just re-worked the orientations of the views as they were incorrect in various cases. This means that if you previously had a "top view", maybe now you need a "bottom view". Big Internal Changes for View Orientation

You should probably re-create these views, together with their dimensions.
[*]Several dimensions don't make sense any more, like a diameter of 0.000 and an angle of Inf....
This is a consequence of the topological naming problem.

What this essentially means is that the edges of the model got a new internal "name", and this confuses the TechDraw dimensioning tools. That is, the TechDraw dimensions are now measuring edges that no longer exist, so they return incorrect values (zero or infinite). To solve this problem, you can just delete the faulty dimensions, and re-create them.
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mcdanlj
Posts: 5
Joined: Sun Dec 01, 2019 12:10 am

Re: TechDraw drawing rendering as only gray window

Postby mcdanlj » Mon Dec 02, 2019 1:47 am

vocx wrote:
Mon Dec 02, 2019 12:00 am
mcdanlj wrote:
Sun Dec 01, 2019 7:11 pm
...
The Vertical-A section is upside down
The author of TechDraw just re-worked the orientations of the views as they were incorrect in various cases. This means that if you previously had a "top view", maybe now you need a "bottom view". Big Internal Changes for View Orientation

You should probably re-create these views, together with their dimensions.
Well, I should re-create those views after I move to 0.19 or later...

Now I know that needing to re-create techdraw views is expected and not a bug. Thanks for the pointer.
[*]Several dimensions don't make sense any more, like a diameter of 0.000 and an angle of Inf....
This is a consequence of the topological naming problem.
I'm familiar with this and expect it when the model changes. I didn't realize that new versions of FreeCAD also can change topological naming, so now I know that too.

As far as I can tell, my particular problem has been narrowed down to "I have a problem that doesn't reproduce on other people's computers and does not reproduce on my computer with 0.19" so there's not much worth investigating. Thanks for the help and I'll get out of the way of future improvements now! ;)
vocx
Posts: 2811
Joined: Thu Oct 18, 2018 9:18 pm

Re: TechDraw drawing rendering as only gray window

Postby vocx » Mon Dec 02, 2019 6:50 am

mcdanlj wrote:
Mon Dec 02, 2019 1:47 am
... I didn't realize that new versions of FreeCAD also can change topological naming, so now I know that too.
...
I would not say this is correct. What you experience looks like the topological naming problem, but I'm not saying changing the version of FreeCAD causes it. Version 0.19 has many internal changes with respect to 0.18. So maybe some of these changes affect your particular model, but it's hard to really know the cause if you cannot really reproduce the error.
To support the documentation effort, and code development, your donation is appreciated: paypal.
chrisb
Posts: 21376
Joined: Tue Mar 17, 2015 9:14 am

Re: TechDraw drawing rendering as only gray window

Postby chrisb » Mon Dec 02, 2019 7:59 am

There was change in OCC, the geometric kernel, between 0.17 and 0.18 which caused changes in topological naming.