motion blur gives false result when using a curve deform modifier and using auto smooth #42819

New Issue

Michael Kirchberger · 2014-12-06T16:27:58+01:00

2014-12-06 16:27:58 +01:00

System Information
win 7 64 pro with gtx 780

Blender Version
2.72b

Short description of error
motion blur gives false result when using a curve deform modifier and using auto smooth

Exact steps for others to reproduce the error
see blend file.
animate a tube along a curve with a curve deform modifier and an animation on the objects's location.
turn on/off auto smooth to see the effect. when using it, the motion blur uses false direction for the blur.

motion_blur_bug.blend

**System Information** win 7 64 pro with gtx 780 **Blender Version** 2.72b **Short description of error** motion blur gives false result when using a curve deform modifier and using auto smooth **Exact steps for others to reproduce the error** see blend file. animate a tube along a curve with a curve deform modifier and an animation on the objects's location. turn on/off auto smooth to see the effect. when using it, the motion blur uses false direction for the blur. [motion_blur_bug.blend](https://archive.blender.org/developer/F129928/motion_blur_bug.blend)

Michael Kirchberger commented

2014-12-06 16:27:58 +01:00

Changed status to: 'Open'

Michael Kirchberger commented

2014-12-06 16:27:58 +01:00

Added subscriber: @Micha

Julian Eisel commented

2014-12-06 16:43:35 +01:00

Changed status from 'Open' to: 'Archived'

Julian Eisel closed this issue

2014-12-06 16:43:35 +01:00

Julian Eisel self-assigned this 2014-12-06 16:43:35 +01:00

Julian Eisel commented

2014-12-06 16:43:35 +01:00

Added subscriber: @Sergey

Julian Eisel commented

2014-12-06 16:43:35 +01:00

Hey @Micha,
afaik, what you do creates sort of a deformation in terms of code (@Sergey correct me if I'm wrong), meaning we need deformation motion blur which is not supported yet. We also had a few similar reports to this (e.g. #42105, #42742), so please look for similar reports before creating new ones.

Nevertheless, thanks for the report @Micha :)

Hey @Micha, afaik, what you do creates sort of a deformation in terms of code (@Sergey correct me if I'm wrong), meaning we need deformation motion blur which is not supported yet. We also had a few similar reports to this (e.g. #42105, #42742), so please look for similar reports before creating new ones. Nevertheless, thanks for the report @Micha :)

Michael Kirchberger commented

2014-12-06 16:58:47 +01:00

okay. thought we have deform motion blur now.
i can turn that on/off for a object. i mean, it renders right when not using smoothing, but renders really slow then.

okay. thought we have deform motion blur now. i can turn that on/off for a object. i mean, it renders right when not using smoothing, but renders really slow then.

Sergey Sharybin commented

2014-12-06 17:06:03 +01:00

Deformation motion blur is for sure supported. The issue here is that auto-smooth might cause topology changes of the geometry across the frames, which isn't supported.

Julian Eisel commented

2014-12-06 17:08:37 +01:00

eek, you're right we have deformation motion blur since 2.71, however, this seems to be a special case. From #42752:

You're trying to use a deformation motion blur on an object which changes topology. Such configuration is not supported and you need to disable deformation motion blur on such objects.

(Sergey)

I guess the same applies when using auto smooth. Again, am I right here @Sergey?

eek, you're right we have deformation motion blur since 2.71, however, this seems to be a special case. From #42752: > You're trying to use a deformation motion blur on an object which changes topology. Such configuration is not supported and you need to disable deformation motion blur on such objects. (Sergey) I guess the same applies when using auto smooth. Again, am I right here @Sergey?

Michael Kirchberger commented

2014-12-06 17:08:39 +01:00

yeah, I see.
I don't actually need the autosmooth, but when I turn it off, the scene renders so slowly, that it isn't the solution for me now.

any suggestions to render faster here?

yeah, I see. I don't actually need the autosmooth, but when I turn it off, the scene renders so slowly, that it isn't the solution for me now. any suggestions to render faster here?

Sign in to join this conversation.

No Label

Download

What's New

Blender Studio

Manual

Developers Blog

Documentation

Benchmark

Blender Conference

Development Fund

One-time Donations

motion blur gives false result when using a curve deform modifier and using auto smooth #42819