Nunchakus

This is my first post ever, so I would like to say howdy to all of yall in the forums.

But now onto my question.

Recently I made some nunchakus but Ive been having trouble trying to get them to be able to hang and swing from gravity. I just read that topic on no joints, so is it still possible to create realistic nunchakus? Ive tried interlocking the chain then making them physical, but instead of having collision with each other, they just fall to the ground?

Any possiblities or ways to fake it?

Hi Kakashi. Welcome to the forums.

Nunchucks are a pretty tuff item to make for several reasons:

1. Objects attached to avatars are always non-physical, so even if you got the chain to work physically, the whole thing would die as soon as you put it in your hand.
   
   
   
2. Even if it weren't for the non-physical attachment issue, there's no way to make a physical chain with links small enough for the whole item to be at proper scale. The physical collision bounding box for all objects is always something like .05M larger than the object itself. That means each link would have to be pretty large in order for their holes to be big enough.
   
   
   
3. Even if all of the above weren't true, physics simulations on toruses are particularly challenging for the servers. Since chain links are toruses, and since each chain requires a great many of them, you can quickly bring a sim to its knees with just a few chains. A friend of mine, a mailer in RL, made a chain mail vest in SL once. It was quite beatiful to look at with its hundreds of individual links, all perfectly placed, but needless to say, as soon as physics were applied to it, it would instantly crash the sim. Obviously, a single chain between a couple of nunchucks wouldn't be as complicated as a chain mail garment, but it's still a relatively complex problem for the physics engine.
   
   
   
4. As for joints, they never worked properly to begin with, and now they don't even exist anymore. They were removed from SL a few versions ago.

Sorry. I know that's not what you were hoping to hear. Hopefully in the future, physics simulation technology will improve to the point where SL can handle stuff like this, but right now it can't.

Unless anyone else knows something I don't, the best you can do is fake the animation with clever construction and texturing, but it takes a lot of work to make it convincing. Basically, you would build a few versions of the nunchucks in various positions, link the whole thing as one object, and then use a script to turn visibility on and off for each version. Time it well, and it can look like the object is actually animating. SL's not very good at timing in general though, so it can be tuff to pull off.

Good luck.

Ok Kakashi. Instead of being a rambling pessimistic pedant today, here is one of the ways to fake it. All you need is 1 cylinder, 1 texture and an animation.

The key is to use the recently introduced flex prim function.

Rez a cylinder and make it about X: 0.3 Y: 0.3 and Z: 0.6.
Edit the cylinder and go to the 'Features' tab and turn on 'flexible path'.
Set the softness to 1.0, gravity to 0.8, drag and wind to 0.0 and tension to 1.0

This should effectively make it bend in approximately two halves semi realistically.
Attach the the prim to your hand and adjust it so the hand holds the non swinging tip.

Any hand movements by your avatar will make the nunchakus swing about. So now all you need is some sort of hand swinging animation. Some of the sword swinging anims work too.

And finally, texture your prim with an alpha texture so that the middle sort of looks like some chains, while the two ends are solid.

Thats it.

D'oh! I totally forgot about flexies.

i wish i'd read this before i tried to make the Ghost Rider avatar........... you could of course make nunchucks the size of a house that would look great and the chain would work, but you couldnt pick it up. i made ghost riders hand chains using flexi-prims, turned out ok, so long as they are at the right angle when looked at

The trouble with flexi-prims is there doesn't seem to be a way (that I've found) to attach the flexible end to another prim that then moves with that end. You can try to create, say, a flail, but what you'll get is the chain part flopping around on the end of the handle while the ball just hangs there in midair.

Now, of course, a whip is ridiculously easy to make because you don't really need anything attached to the business end of it.

I think the thing to remember here is that the RL original nunchaku used rope, not chain. So if you can connect it to a flex, you're golden, even if it doesn't look chainy.

Well if you can figure out how to make the business (whippy) end of a rope, chain, or anything else made as a flexi-prim move an attached non-flexible object with it, please do let me know. Presently, I believe it to be impossible.

Of course, you could JUST use the noodle.. and SKIN it to include the handles on the noodle. Wouldn't be perfect, but it might be passable



(the red would be transparent)

I suppose you could sort of fake it like that. It wouldn't be close to the standards I expect of myself in my own builds, but it might make someone who just desperately wanted nunchaku happy.