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Update problem with a simple driver based rig
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System Information
Win 7 SP1

Blender Version
Broken: 2.71

There's something wrong with the way Blender handles driver related rigs. In the scene that I'm working on, I linked the "HATCH" object from the file "HATCH.blend" There is simple transform driver based opening and closing rig system on it. I uploaded this one to RenderStreet ( to render it out, and when the frames started coming out, I saw huge motion blur on the hatch, which was supposed to open rather slowly. You need to pack your blend files before uploading to RenderStreet, so the hatch in the scene I'm sharing with you is embedded, rather than linked. But it matters not, because when I opened the "PL10_RV01_01.blend" file, in which a proxy was created to animate the hatch rig, I found that when you rewind, the hatch is ill-responsive to the animation on its rig. Only when you click on the go to first frame button once or twice, does it respond correctly. But the nodes on the render farm see this as a huge jump, hence the huge motion blur. What gives???

Way to reproduce this:

1- Download the files from and Open the "PL10_RV01_01.blend file"
2- Locate the packed "HATCH" object. You can also solo its layer.
3- Playback the animation, you'll see that the driver driven location of the object is not consistent.
4- Press the Go to first frame button, you'll see the inconsistency even better.
5- I'm also sending the source blend file named "HATCH.blend" for you to check out.



Event Timeline

Ajlan Altug (jacobo) raised the priority of this task from to Needs Triage by Developer.
Ajlan Altug (jacobo) updated the task description. (Show Details)
Ajlan Altug (jacobo) set Type to Bug.

Yes, it seems the hatch is always one frame/update behind its driver… Joshua, not sure here, I know we have some known issues with drivers and update, is that one part of it?

Bastien Montagne (mont29) lowered the priority of this task from Needs Triage by Developer to Normal.Oct 10 2014, 9:56 AM
Sergey Sharybin (sergey) closed this task as Archived.Oct 14 2014, 3:14 PM
Sergey Sharybin (sergey) claimed this task.

This is a famous fake dependency cycle bewteen object and it's bones. That's exactly what we're now trying to solve with @Lukas Toenne (lukastoenne) here in the studio now.

meanwhile you might play around with Extra Update flags in the object's extras panel.

Thanks for the report, but for now it's a todo.

Ok, god speed to you guys... Hope you can get to the bottom of it cuz one rigs a lot of stuff like this :)