Shrinkwrap modifier does not work with multiple scenes and VSE #42658

New Issue

Benoit ROUSSELLE · 2014-11-20T08:44:25+01:00

Benoit ROUSSELLE commented

2014-11-20 08:44:25 +01:00

System Information
Debian GNU/Linux jessie (8/testing)

Blender Version
Broken: 2.72b 9e963ae

Short description of error
using shrinkwrap modifier to hide/reveal text object in a single scene works as expected.
using previous scene by importing it in VSE in another scene does not work in 2 cases:

when trying to render in batch mode
when opening the file and try to render without viewing the HideReveal scene.
Please check details below as it does work again in interactive mode if you view the scene and refresh the sequencer.

Exact steps for others to reproduce the error
Please see attached file for the example.
Description of the setup:

loaded factory settings
2 scenes:
- "HideRevealText" : short animation with text that has Shrinkwrap modifier applied. Plane rendering is disabled outliner view
- "Scene": we import HideRevealText scene in VSE.

When you do all this for the first time, everything works as expected in scene "Scene"
Now you save and close the file.

With the example file:

Open it and try to render at current frame (15) (without doing anything else !): you see the bug, as full text object is displayed.
Go to "HideRevealText" scene, come back to "Scene" scene, refresh sequencer: bug as disappeared. Move cursor: you see the right animation.
batch mode bugs: blender -b bugShrinkwrapMod.blend -F PNG -s 15 -e 15 -a

I have also tried to not use the "disable rendering Plane" in the outliner by using the layers + node compositing, but the result is the same.
I can provide the file if this is usefull.

Thanks a lot, blender is such a wonderfull piece of software !!
Cheers,
Benoit.bugShrinkwrapMod.blend

**System Information** Debian GNU/Linux jessie (8/testing) **Blender Version** Broken: 2.72b 9e963ae **Short description of error** using shrinkwrap modifier to hide/reveal text object in a single scene works as expected. using previous scene by importing it in VSE in another scene does not work in 2 cases: - when trying to render in batch mode - when opening the file and try to render without viewing the HideReveal scene. Please check details below as it does work again in interactive mode if you view the scene and refresh the sequencer. **Exact steps for others to reproduce the error** Please see attached file for the example. Description of the setup: - loaded factory settings - 2 scenes: - "HideRevealText" : short animation with text that has Shrinkwrap modifier applied. Plane rendering is disabled outliner view - "Scene": we import HideRevealText scene in VSE. When you do all this for the first time, everything works as expected in scene "Scene" Now you save and close the file. With the example file: - Open it and try to render at current frame (15) (without doing anything else !): you see the bug, as full text object is displayed. - Go to "HideRevealText" scene, come back to "Scene" scene, refresh sequencer: bug as disappeared. Move cursor: you see the right animation. - batch mode bugs: blender -b bugShrinkwrapMod.blend -F PNG -s 15 -e 15 -a I have also tried to not use the "disable rendering Plane" in the outliner by using the layers + node compositing, but the result is the same. I can provide the file if this is usefull. Thanks a lot, blender is such a wonderfull piece of software !! Cheers, Benoit.[bugShrinkwrapMod.blend](https://archive.blender.org/developer/F124996/bugShrinkwrapMod.blend)

Benoit ROUSSELLE commented

2014-11-20 08:44:25 +01:00

Changed status to: 'Open'

Benoit ROUSSELLE commented

2014-11-20 08:44:25 +01:00

Added subscriber: @BenoitROUSSELLE

Benoit ROUSSELLE commented

2014-11-20 08:47:21 +01:00

Sorry forgot to say i use Intel HD4000 card.

Antonis Ryakiotakis commented

2014-11-20 11:35:23 +01:00

Added subscriber: @Psy-Fi

Antonis Ryakiotakis commented

2014-11-20 11:35:24 +01:00

Confirmed, looking into it

Antonis Ryakiotakis self-assigned this 2014-11-20 11:35:39 +01:00

Antonis Ryakiotakis commented

2014-12-04 20:32:25 +01:00

Added subscriber: @Sergey

Antonis Ryakiotakis commented

2014-12-04 20:32:26 +01:00

Alright, I've spent a good part of the day looking at this. So looks like the reason this fails is that the derived mesh of the plane won't get calculated and thus the text object won't have a valid derivedmesh to intersect against. Easy workaround for the reporter here is to just reenable the render flag for the plane, so the plane mesh but this won't fix the underlying issue of course.

To fix this I need @Sergey's expertise again (sorry for the constant nagging but DAG is really new code to me). Basically, as far as I have seen, on file load, the objects of the current scene will get tagged for update at least once in DAG_on_visible_update, so they all get their derived meshes calculated at least once. For scenes referenced in the sequencer, this doesn't occur, so it's possible to get invalid derived meshes, such as in this case. Forcing drawing like above works here, but the calculation of the derived mesh in time for the other modifier depends on order of drawing so it's not a very good workaround.

What we could do, is make dag_current_scene_layers also include any scenes that are referenced on sequencer strips but that may have performance or other implications. Other solution is to just do that with a specialized function on file load, which only takes updates the sequencer objects just once.

Alright, I've spent a good part of the day looking at this. So looks like the reason this fails is that the derived mesh of the plane won't get calculated and thus the text object won't have a valid derivedmesh to intersect against. Easy workaround for the reporter here is to just reenable the render flag for the plane, so the plane mesh but this won't fix the underlying issue of course. To fix this I need @Sergey's expertise again (sorry for the constant nagging but DAG is really new code to me). Basically, as far as I have seen, on file load, the objects of the current scene will get tagged for update at least once in DAG_on_visible_update, so they all get their derived meshes calculated at least once. For scenes referenced in the sequencer, this doesn't occur, so it's possible to get invalid derived meshes, such as in this case. Forcing drawing like above works here, but the calculation of the derived mesh in time for the other modifier depends on order of drawing so it's not a very good workaround. What we could do, is make dag_current_scene_layers also include any scenes that are referenced on sequencer strips but that may have performance or other implications. Other solution is to just do that with a specialized function on file load, which only takes updates the sequencer objects just once.

Benoit ROUSSELLE commented

2014-12-18 07:53:54 +01:00

Dear Antony,

Thanks for the investigation, and the workaround !

Benoit.

Dear Antony, Thanks for the investigation, and the workaround ! Benoit.

Sergey Sharybin commented

2014-12-26 11:16:38 +01:00

Changed status from 'Open' to: 'Archived'

Sergey Sharybin closed this issue

2014-12-26 11:16:38 +01:00

Sergey Sharybin commented

2014-12-26 11:16:38 +01:00

@Psy-Fi, using current DAG_on_visible_update would only solve situations just after loading the file. If you'll start switching scenes, layers etc and going back to VSE it's still really simple to run into situation when objects needed for visualization wouldn't get updated.

I wouldn't consider this a bug for now, it's a TODO to be handled by the depsgraph_refactor branch.

@Psy-Fi, using current DAG_on_visible_update would only solve situations just after loading the file. If you'll start switching scenes, layers etc and going back to VSE it's still really simple to run into situation when objects needed for visualization wouldn't get updated. I wouldn't consider this a bug for now, it's a TODO to be handled by the depsgraph_refactor branch.

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Shrinkwrap modifier does not work with multiple scenes and VSE #42658