Cineversity

I have an R12 project involving a falling object which has soft body dynamics applied. Of course, when the object impacts the floor - it bounces and wiggles similar to jello. Then text flies in and stops - which wiggles due to the jiggle deformer being applied. Both the soft body dynamics and the jiggle worked perfectly. Then I re-rendered the animation - but this time applied scene motion blur. The motion blur looks excellent… but to my surprise, the falling object now behaves like a hard body - it bounces off the floor but no longer has squash and stretch or wiggle. In addition, the text that flies in no longer responds to the jiggle deformer. Again - I changed nothing about the project except for applying scene motion blur to the render.

Does anyone have any insight? Is this a bug in R12? Or is there something I am missing?

Thank-you in advance for your assistance,
Larry

Likely it is just an incompatability of effects that is only rearing it’s head at render time.
Try baking your dynamics, in cases like this it is usually the solution.

Grateful for the help, Patrick!
Baking the dynamics sounds like a great solution. I understand in theory, but just tried it and only the object was baked. Could you direct me to a tutorial featuring baking the animation and deformation of soft body dynamics in r12? Or is it simple and I’m just missing a step?

Thanks Again!
Larry

You should just be able to select the cache tab of your softbody tag and click cache.
In my rudimentry test with a cube and a jiggle deformer w. falloff it looks like the effect of the jiggle is even baked into the softbodies cache at that point.

open the file, play through with jiggle enabled, then disabled.
Next, make sure the jiggle is enabled then cache the file.
Also notice if you disable the jiggle deformer after caching you will break the cache.

Hi Patrick,
  Your instructions on baking dynamics were excellent - I didn’t realize how easy it is to do! And thanks for including a basic example - that provided clarity.
  Unfortunately, baking did not resolve the problem on my project. Soft body dynamics are still disabled in the render if scene motion blur is activated. I’ll provide some additional specificity: The falling object is Text. To my understanding, soft body dynamics do not work on text, so I put the text inside a cube which has the mesh deformer applied to it. This worked excellently and rendered with all the squash and stretch one would expect from a soft body - until rendered with scene motion blur.
  I’ve attached my C4D project - perhaps you can easily identify a resolution or workaround. To reduce the size of the project file (to make it small enough to post), I cleared the cache on both the jiggle deformer and the dynamics - so you’ll need to click “Calculate” and “Bake”.
  You and Dr. Sassi are SO appreciated! THANK-YOU for your assistance.

  Larry D

Looks like it is just a bug due to using a primitive for the Mesh deformer cage.
If you convert the cube to polygons then bake it should work fine.

Hi Patrick,
    You are my hero! This completely cured the problem! Yes, I’ve also found that there are usually less potential problems if primitives are made editable - but in this case it didn’t occur to me to check for that. Great catch.
    I needed this project to be completed by the weekend, so THANK-YOU for spending the time to follow this through until it was resolved. The next time you’re coming to Phoenix, send an email to let me know and I’ll buy you dinner.

    Warm Regards,
    Larry

Happy that helped Larry.