Weighted Rotations

Hello everybody! (It’s my first post.)

I’m a long-time LightWave user and a few months ago I decided to add Blender to my pipeline. At first just for character animation but as I’ve learned it (with the help of the Blender for Dummies book) I’ve decided to use it for even more.

The reason I’m posting is to share one of the techniques I use, and to also ask about how to better replicate it in Blender.

One of the workflows I like to use in LW’s Modeler is to use a weight map to control the falloff of a tool (like the move, rotate or scale tools) making them much more powerful. I wrote a bunch of L-Scripts (LW’s scripting language) which apply the weight map values in a variety of ways.

Between Blender’s Array modifier and Proportional Editing Tool I have some of that same functionality that I was getting by using weight maps. But I’m wondering if adding “Vertex Group” as another falloff type to PET would be useful (to anyone other than me). Or having some sort of extra option in the Hook modifier, since it could then be animated.

At this last Siggraph I actually asked Brecht if it would be possible code-wise to control PET with weight values. He said that it was possible but that I could also try using a Hook.

I did try using a Hook modifier, and it works almost exactly as I wanted. Moving and scaling the hook object works as expected. Rotation on the other hand, not so much. Instead of an arc I get a straight line.

Attached are some files that help explain what I’m after. Here is also a link to a Blender python script I wrote that performs weighted rotations:

Everyday I’m still finding new things in Blender so maybe someone here knows of another tool that could give proper weighted rotations.

Here’s a page with some videos I made that demonstrate some of the things that can be done with the L-Scripts I wrote. The video for: Using a spline with Weight Outward and the one for: Making springs via Weight Extend, both show the kind of things I’d like to do:

I do plan on porting some of those scripts to Blender.

Thanks for reading this rather large post.


Spring.blend (270 KB)NoArc.blend (172 KB)