Drivers broken on both 2.81 and 2.82

Archive Usability
1

Hi,

I found pretty much a huge bug. Drivers are broken when referring to itself.
(Happens on both Eevee and Cycles for 2.81 and 2.82)

PROBLEM
Here is an example with a simple cube :

  • Cube is animated on X position
  • Cube’s X rotation is driven by X position

Viewport “looks” ok :
viewport

But Render is not updated at all :
render_broken

SOLUTION (a “trick” to workarround the bug)
Only way to have it working is :

  • Setting an additionnal empty
  • Setting a constraint on the Cube to copy empty location
  • Setting the Cube’s driver on empty location

Viewport works :
viewport_empty

And render is ok :
render_ok

But it’s not “solution”, only a trick, and the bug is still there.
Please note that, in addition, in the first case, the driver update is very laggy when moving current animation frame. It’s like when you have a dependency cycle in an armature, whereas here it’s just X position driving X rotation.

Is this bug known ?

See you :slight_smile: ++
Tricotou

2

reported the bug 5 min ago
https://developer.blender.org/T71540

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