Houdini, Redshift

Vellum Shaping RND

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Vellum shape morph RND result

Some explorations steps with vellum & shapes

Here are some notes/gifs on finding a solution and strategies for creating a morphing effect in Vellum simulations. What kind of sources and constraints you are using ultimately comes down to dealing with the SOP Solver in DOP land. Adding and deleting Geometry/ConstraintGeometry requires some work-arounds and attribute pre-passing.

Overview
Overview DOP setup

For the deforming i use and recommend this free HDA:

gumroad.com/l/cfxwrap

Insightfull video for point deforming :

youtube.com/watch?v=FKUJcXB33oM

Example issues ADDING Grains & Constraints:

Velocities exploding after adding new grains and constraints
With clamped max. solver velocities
Values on added grain-pts that has to be set to zero

How to predict where adding Grains?

I just use a heuristic approach, where i just “Point Deform” the hole constraint space to estimate a approximation where the new grains should appear. This leads sometimes in bad solutions and breaks the hole simulation. But in most cases, it works.

Adding with very stiff grain “prediction”
Adding with a sloppy grain “prediction”
Calc the stiffness values before substracting constraints

Example issues DELETING Grains & Constraints:

Unwanted impulses after deleting the first 4 Grain points and constraints
With a pre-pass, that calculates the stiffness for the elements which gonna be deleted

Deforming Geometry and UV-sets blending:

uv & uv2 blending per point attribute