Houdini and Redshift Tutorial - Growth effect in Houdini. VDB and one geometry cut trick.

This time, let's open Houdini Side FX and learn a growth effect technique together.
Everything is possible and there are so many ways to complete the same effect inside a Houdini, so this is only one thought about how to accomplish it.
Here is the same setup from a hero Houdini user with much more (around 04:50)
• Houdini is only Stupid...
Also, you can check such a great collection of other videos for the same growth but with a variety of approaches
* this growth vdb node * • Houdini | VDB Morph SD...
* sdf explained * • SDF example 1: samplin...
* point based growth * • FMX Special: A Point B...
* learn some Chinese * • 用houdini的VDB制作超实用生长动画-...
* quick geometry growth approach * • Houdini 30s Quick Tip ...
* all you need to know about attribute growth * • VFX Essentials - Attri...
* vdb noise growth * • VDB Advected Growth | ...
Have some fun!
00:00 - Intro showcase
00:52 - Prepare a model VDB creation
05:31 - VDB morph node
07:10 - Solver SOP
10:25 - Create a noise mask
13:00 - Back to the original scene
13:55 - Create a wave on the edge
19:33 - POP Network review
20:50 - Geometry clip based on the mask. P to UV and back
25:00 - Redshift render settings overview

[@Atmospirit]

Thank you so much, it was really helpful.

[@spiderbrr]

I really liked your tutorial, I just missed the explanation of the points above about att transfer.

[@purplelight2947]

I used attribute transfer node to copy my mask attrib. On the left - the geo itself with mask = 0 in point wrangle. On the right is the geo of the growing VDB we created earlier. And another point wrangle with mask = 1. So now whenever we have growing geo we have mask attribute on the static bottle. I hope that makes sense.
Alternatively, you could use pyro spread to generate an organic growth effect on the geometry. Or non simulated methods with further remapping of the parameter. whatever you like the best
check these videos for more info
- th-cam.com/video/0FX7tcrYR_0/w-d-xo.htmlsi=7CwnEt1wonn_l0Nj
- th-cam.com/video/b7e9wnDBI78/w-d-xo.htmlsi=G33kDS0kcXWpYdpx
- th-cam.com/video/glUV4FnOC4M/w-d-xo.htmlsi=Sj4UHkrmu4bfUzKk
- th-cam.com/play/PLqA3grGAK2LtDBZpMeS8R5fB8dIM9iUrc.html&si=Ym9dHSuFQk96RNtN
and then you use the mask to displace a geometry.

[@johnwalker4787]

Cool tutorial. I know thickness is needed for VDB. But why did you delete the inner wall first and then extrude it back ?

[@purplelight2947]

thanks !
I think it was a model-dependent situation. In that particular case, the topology of the model inside was just a weird cut shape. So I wanted to have a "true" thickness, not ended at the top of the bottle inside. I selected a loop and deleted everything inside. And then, as you said the VDB requires to work with extruded geo. I added the extrude back but this time all the surface of the bottle was extruded. Hope that makes sense.

[@Atmospirit]

Why grow speed isn't linear?

[@Atmospirit]

it grows fast and than slows down

[@purplelight2947]

Just personal motion preference.

[@RUMIYofficial]

how do make the bubbles

[@purplelight2947]

there are 3 particle simulations for the bubbles. All started from the edge of the glass.
19:33 1 - just simple pop network with wind effect down with noise and some pop drag.
2 - the same for bigger bubbles, but the wind is not that strong and pop drag on the opposite is much stronger. and xyz distance function to stick the particles to the surface of the glass. so that will restrict the bubbles in the motion given the illusion of being inside the glass.
and simple redshift particles.

[@LamekFelix]

Not working in H20, any tip?

[@Atmospirit]

which step?