How to scale global physic simulation?

metaclay · March 21, 2019, 1:28am

Hi i have 3d camera tracked in Nuke and i exported to fbx. I want to import this fbx into Blender and apply physic simulation. I have some problems here :

I use fbx import command in blender, but this importer has problem , i never get the correct Y rotation ( the Y rotation is always inversed). Anyone know how to fix this ?
I end up using a script https://www.youtube.com/watch?v=Cw-PEyekQz0&t=211s
It works fine and It fixes the rotation issues but the problem is : when importing , i can’t adjust the scale of the scene. So all the objects came from Nuke is 1/100 smaller in Blender. In this case , of course all the physic simulation will fail. How can i scale up the scene correctly including all the camera animation? i can’t just simply select all and scale up , because the animation won’t scale up. I need to scale the scene by 100x for physic simulation to work. How can i do this ? i tried to alter the ‘unit scale’ in the scene parameter but has no effects. Does anyone here know how to solve it ?

Thanks
Andi

yogyog · March 21, 2019, 9:23am

I think… when importing your FBX you open up the left panel and look bottom left, you’ll find a panel of options when importing an FBX. With a bit of experimentation, you may find the solutions to your scaling and rotation problems here.

metaclay · March 22, 2019, 9:34am

Yes, i used that parameter but none of them can give me the correct orientation.

yogyog · March 22, 2019, 10:05am

Can you parent all the unparented objects to an empty (you’ll see these in the outliner)… then rotate and scale the empty?

metaclay · March 28, 2019, 1:40am

I find a way to fix the rotation , this is my setup in fbx parameter : turn on manual orientation and set forwar to -Z forward and up to Y up. Then DO NOT use the camera directly , but used it as reference only. Create a new camera, go to constraint property and choose ‘child of’ and select the original camera as parent. now clear out all translation/rot/scale of the new camera and set X and Z rotation to 180. Now if i see through the camera, it will fix the problem.