[Tutorial] Chain Physics (Moving 3d Models)

In this tutorial, I'll be teaching you how to take a rigged 3d model and use the chain physics template on lens studio to create 3d models that move when you move.  Check out my example lens below.

Lens:https://www.snapchat.com/unlock/?type=SNAPCODE&uuid=d9f789ec62024bb99b694f3cf9f9c555&metadata=01

In my example, I have taken my 3d model, placed it into blender, and rigged it with bone so that it is ready for blender animation, or for what we're doing, chain physics.  If you don't know how to rig objects in blender check out this tutorial here.

Tutorial: https://www.youtube.com/watch?v=ZmiZ6VkSJBE

The first thing you'll want to do is open up the chain physics template in Lens Studio.  Then delete all the template pieces besides the helper scripts.  Create a head binding and begin placing your models around the face or head how you'd like them.

Once done drag and drop the ChainController script from the scripts folder onto one of your first bones or a scene object like so.

From there the bone structure starts with the bone closest to the middle of the flower for me.  Bones will extend out from where the origin point is, this is mirrored in snap hence the order being bone 1, bone 2, and bone 3.  Set your joint 0 value to the bone your first section will originate from.  Since my model is a flower I created a bone in the center where all the petal bones connect to.  Then continue to add values and put your bones in order, once your happy with the set up you can customize the gravity the bones and your model will feel.  I set my stiffness to one and set the type to rigid so the flower petals would stay straight and wouldn't twist around.  Then to tighten them down, I tweaked the force for each petal.

You can easily rig bones with any 3d model and with this tutorial you can allow them to be fluid and move around with the simulated gravity!  

Happy Creating,

Ryan