"Tadpole" Rigging test

At the Blender Conference (the Australian one, I’m too cheap to travel to Amsterdam) one of the many things that happened was the devising of a rig to make things like tentacles - where you’d only have to move the base object and all the tentacles would follow it around.

This is the result:


http://users.quickfox.org/~phlip/content.php?module=tadpolestory <-- the story behind it, but watch the avi’s first

quickfox.org has since collapsed, but I managed to save the text of the page:

At the conference, between people showing various techniques or their artworks on the projector, people were just wandering around, experimenting with blender, seeing how other people did things, etc.

Neil was trying to figure out a problem - they had an object with tentacles (I think it was an octopus) and they wanted to be able to animate the octopus and have the tentacles flow automatically.

Well levon and I thought about this for a while, and eventually figured out a nice way to do it (which I’ll be writing a tutorial for eventually) and I made a testing scene. Just as the usual testing object for the game engine is a sphere with a point out the front so you can tell which way it’s pointing, I decided to use a sphere with a long tail.

Big mistake.

Neil thought it was a tadpole, but everyone else thought it looked more like a sperm - and quite a few thought it was intentional… I gave in to demands to make the material translucent, with high amounts of fresnel (the effect that makes it transparent in the middle, but opaque at the edges) and a slight Emit for SSS - this is when I added the checkered box so you could see the refraction.

Neil was (jokingly) upset a bit about me making it more sperm-like, so I tried to make it more tadpole-like - I added a (really dodgy) mouth to the front, and changed the colour to green. Unfortunately with the Emit the way it was this just made it look radioactive… so I added a green lamp to its head and called it a day.

As for the Suzanne… well… I just thought it would look pretty, and it did.

Very nice… but I can’t access your “backstory” page from any of 4 browsers. Can you explain how you did it?

Well… tadpole wasn’t the first thing i thought of, and after reading the story, I can see I wasn’t the only one. :wink:

I am interested in how you accomplished it though. In the suzanne one, there seems to be some weird deformations occasionally, but overall, it looks very interesting!


this is very interesting - can we see the rig?

Oops, I haven’t been checking elYsiun recently and missed the replies…

akator: quickfox isn’t the best host, it goes down sometimes without warning and runs rather slowly… but it is free and doesn’t have ads which kind of makes up for it…

NateTG: the weird deformations are part of the fact that I added some random “twitching” to the tail to make it look like it was using the tail to swim rather than the tail just following it, and I think it was a bit too strong. Also when it goes upside down the track-to’s get weird when they realign themselves with “up”

Basically what I did was have a series of bones along the tail, each tracked to an empty initially sitting right on the joint of the bone. Then I parent each empty to the one before it with a time offset of around 10 frames, and it all works. For the twitching I just added a small wave to each of dLocX/Y/Z for the first empty, and just let that propogate up the tail.