16 replies to this topic

[Jason]

Hi guys,

Here is a challenge for you all: how do you make a good system for a helical cable; like telephone cord or like a slinky dog? The challenge is to come up with a good system where the user can specify two ends and the centre section droops realistically. The more intuitive artist controls and system stability are of utmost importance for this type of system in production. We don't want to struggle endlessly with the behaviour and the look of the droop. Secondary animation is also a bonus.

How about that? Think of the Slinky dog in Toy Story, or a character on the telephone.

Sound good?

Lets do it!
Jason

[AndrewVK]

Expression driven solution + CHOP driven secondary motion (spring like)

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[D'n'D]

Couldn't miss the fun. Et voila, mes dames et messieurs, here is my two cents that consist of SOPs and Expressions.

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[Andrei_S]

ofigitelno
Andrew skin scenky?

[Stremik]

Andrei_S, on Sep 24 2003, 09:25 PM, said:

ofigitelno

                    Ñâîè!

[concept4]

Here's mine
SOPs and expressions.
Plenty of attributes added to control almost any aspect of the look.

--Ronnie

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[hoknamahn]

How to evaluate cabel's whipping?

[Jason]

I have another entry from a submittor that describes the caternary curve and the spirals completely in VEX; a really clever entry indeed.

Can we peek at each others' answers now?

[AndrewVK]

This the first that has come to mind.
The second arrival was also... But here has left a "LockOn" demo.
Just open scene and hit play. (6.1.128)
Bypas "add_secondary_motion" node to edit endpoints.
Not so clever...i know...sorry guys...
i cant shake it...damn i`m hit...Eject...Eject

Attached Files

•  cord.zip   23.43K   597 downloads

[D'n'D]

I slightly modified the file to use some CHOPs instead of the Expressions, since, it's faster. But, this is still the brute force approach. I know, I know... Doctor Aizenk Houdini won't be too happy with this "solution".

PS.Andrew, I hope the ejection was done by K-36, so, you'll be able to fly again in a month or so.  

Attached Files

•  helical_cable.zip   23.24K   526 downloads

[D'n'D]

SOPs & CHOPs

OK, gentlemen, I didn't like much the elegancy of my first attempt. So, having borrowed a couple of ideas from Andrew V.K.'s solution, I came up with this hybrid one, which is very simple, but good enough to achieve the goal.
There is no MIN/MAX limits, so, it is up to an artist to keep the look believable.

P.S. IMHO, Jason, a telephone cord and a slinky dog are not quite similar in behavior. So, it's much easier to make two kinds of springs for animation, instead of trying to fit both in the same shoes. But, it's just IMHO.

Attached Files

•  spring_cord.zip   20.15K   511 downloads

[AndrewVK]

D`n`D taki da K36 vinesla
U tebia v point2 sop ostalsia expression
kotorii ne praciue. On ispolzuet stamp
fichu kotoraia stampit rastiazhku individualnogo
segmenta kotoraia raschitivalas v vex builder.
Poskolku takogo atributa u tebia net to etot point sop
prosto rastiagivaet ego na 1...no join
taki delaet svoe delo...hotia na extrimalnoi
rastiazhke budet zametno.