Odds And Ends 02

This is a vex-driven cube fold/unfold using a hierarchy of matrices in a parent/child relationship. Crazily useless!

hipnc file

Odds And Ends 01

I thought I would collate together some of the scenes I've been experimenting on and posting on forums - more for my own reference than anything else!

The first is based on an ICE setup for grooming feathers that Psyop demoed a few years ago. It establishes a local reference frame on each point and then interpolates between multiple guide nulls to orient 'feathers' relative to that local orientation. I was hoping to use the new array slerp vex function introduced in 16.0/16.5 but I couldn't get predictable results from it so reverted back to a rough and ready 'piecewise' quaternion slerp to get a weighted average. I am absolutely positive there are much simpler ways in Houdini to achieve the same effect!

hipnc file

Smoother Reference Frames on Curves

I used this paper on Parallel Transport Reference Frames and some great advice from Andy Nicholas (who did a better version in a tenth of the time!) to make a tool to construct smooth reference frames on curves with twist and rotation. Hipfile (NC) is here.

Houdini Branching Structures

First attempt to do some branching in Houdini. Nothing new really. There's a silent walk through of the main controls on Vimeo here. It's based on some of the concepts in Fabricio Chamon's brilliant Strand Tree ICE compound. It consists of a simple iterative paradigm where at each iteration n number of branches are generated and some kind of multiplier is worked into the length, width, angle etc. This multiplier can be attenuated by a 'reduction/increase' factor per iteration or by using a ramp. There are parameters to control the growth and colour with normalised attributes like distance, u etc and these are all left exposed.  I hope the video makes it clear. The 'to do' list is massive - proper topologically correct junctions (without hacking it with Fuse or Polygons to VDB) would be great! The full .hip file is here. Any tips most welcome - interface or performance enhancements!