Morph to triangles

[caskal]

Hey guys, 

Just watched the awesome work of Aixsponza and I'm wondering how to achieve this kind of effect, I let the video below and some still frames first

Are they using vdbs for morph? and attribute transfer to drive the transformation? as for the triangles effect, a poly reduce with poly extrude or some point vop to extrude them? I really love this kind of morph transformations and any insight on how to aproach will be helpful

 

Thanks!

Edited November 12, 2016 by caskal

[f1480187]

There are two animated meshes composited with soft pixel mask, due to visible mismatch between them. The mismatch is from low-frequency noise animation on spiked mesh, I think.

Spiked mesh may be quite coarse and it doesn't need to contain every small detail of the fine mesh, it can contain reasonable amount of meshing artifacts on the nearby area. So, it is easy to create one. You can make spiked mesh by creating lowpoly triangle mesh, then extrude and beveling result. Compositing mask could be rendered with the value used to drive animation, then clamped, blurred, painted, etc. In my case @zscale used to extrude primitives should be enough to start with.

Getting isotropic triangle mesh procedurally in Houdini is not trivial if the number of triangles is very low. You will loose volume and get bad shaped triangles (all triangles at the ear tip area are bad, for example). To get better triangles, you need to do manual retopology. It's easy to make a few triangles, anyway.

spiked_ear.hipnc

 

Edited November 16, 2016 by f1480187

[caskal]

Hey @f1480187 

Good catch on the mask, I always tend to think that everything is done at once instead of having a compositing mind.

This was my test with my limited knowledge, its a much simplier setup than yours, remesh, poly extrude and a attribute transfer, what I didn't know is how to drive the grow in a more organic way (I'm analizing your file slowly to get the zscale stuff)

Will keep studing your hip, thanks once more for your time helping me, I really appreciate!

 

[f1480187]

I also used placeholder animation with AA noise animated by Y axis. @zscale primitive attribute simply multiplies Distance value on Poly Extrude node. Here is simplified example with some additions to zscale driving setup.

zscale_stuff.hipnc

 

[caskal]

@f1480187 in love this smooth setup, what I was reading about was the "abs" and "pow" inside the VOP, never used it before, readed what it does and also deleted to see the function and I get it now.

Also didn't know about using the attribute transfer in that way.

I still strugling with the wrangles, but starting to understand them slowly, last question:

On the solver accumulate: @zscale = max(@zscale, @opinput1_zscale); -->  @zscale and @opinput1_zcale aren't the same thing?

and on the Blend: @zscale += @opinput1_zscale/1.5; --> same doubt, I get the division but confused by the opimput, this is refering to the first input of the node?

What are these doing exactly? I get the names, but I disabled them and I get almost the same effect, less organic tho. 

Thank you!

 

 

[f1480187]

The contents of VOPnet is quite random, it's merely adjusting the value. I start with only noise, and place nodes later, by observing actual extrude result. @zscale and @opinput0_zscale are same thing, but only if you didn't change @zscale in this wrangle. Otherwise, @opinput0_zscale will be original @zscale value. Accumulate solver just remembers a maximum value from all previous frames. Blend wrangle makes it less strong, allowing areas to fade a bit, if the noise goes away.

Edited November 17, 2016 by f1480187

[caskal]

@f1480187 Thanks a lot once more for sharing your knowledge and your time man, I really appreciate, love the result of this setup, will experiment to adapt to other motion stuff.

Btw I just uploaded some Shoe render practice http://cargocollective.com/caskal/Inspired-by-Nature

Cheers!