Ragdoll and cloth physics

Sage
Posts: 1,482
Joined: 2002.09
Post: #1
I've been trying to make a physics system that would allow soft and rigid body simulation. It's mostly been done using a lot of geometry and trig, with a algorithm for every plasible type of collision and movement.
I've made it way too complicated every time and have never made anything working. I keep thinking that there should be a simpler way, after all it's only an approximation.

Does anyone have some simple example that they have made? Like a simple chain hanging from a ceiling? A link maybe to a site that has this kind of information.

Scott Lembcke - Howling Moon Software
Author of Chipmunk Physics - A fast and simple rigid body physics library in C.
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Member
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Post: #2
One point connected to another point? Wouldn't you just start with the affected point, then work outward with a simple formula to figure the angle/velocity relative to the first point and second point?

I'm just guessing/thinking.

"Most nutritionists say that Twinkies are bad. But they're not, they're very very good."
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Sage
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Joined: 2002.09
Post: #3
Well that's what I tried, but it get's really complicated when you realize that one point moving affects all the others in the system. That's what I mean when I said that an approach using just simple geometry doesn't really work very good.

Scott Lembcke - Howling Moon Software
Author of Chipmunk Physics - A fast and simple rigid body physics library in C.
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Member
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Post: #4
There's an article on Gamasutra about Verlet particle systems that may be what you're looking for. I don't have the link handy, but it's called something like "Advanced Character Physics".
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Tycho
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Post: #5
http://www.gamasutra.com/resource_guide/...n_01.shtml

Free membership required, but you won't regret it.
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Member
Posts: 114
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Post: #6
I mean work outward from that point, using the same formula for each new set of directly connected points.

Still complicated as far as sorting them though.

"Most nutritionists say that Twinkies are bad. But they're not, they're very very good."
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Moderator
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Post: #7
NeHe has a tutorial on rope physics, if that's of any helpĂ–

Mark Bishop
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Student and freelance OS X & iOS developer
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Luminary
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Post: #8
I highly recommend the Gamasutra article.

I have a C implementation of some of the things in the article, if anyone's interested. My email's in my profile.
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AJ Infinity
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Post: #9
get the book Physics for Game Developers also. Also check out the Havok physics engine. (one of the best on the market.)
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Luminary
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Post: #10
I seem to recall that the general concensus was that the physics for game developers book wasn't worth the paper it was printed on.

As for Havok, looking at it is a purely academic exercise. They won't even give an evaluation version to anyone who isn't a major North American game developer, and the assumption is that if you're interested in Havok you can afford the price, whatever that might be, 'cos they sure aren't saying...

A more useful suggestion would be to check out ODE, which is at least free...
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Member
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Post: #11
Quote:Originally posted by OneSadCookie
As for Havok, looking at it is a purely academic exercise. They won't even give an evaluation version to anyone who isn't a major North American game developer, and the assumption is that if you're interested in Havok you can afford the price, whatever that might be, 'cos they sure aren't saying...


Actually Havoc is included with Macromedia Director (or was in 8.5, not sure about MX) $1100 is a little hefty for the average schmuck, but it's certainly not out of range.

---Kelvin--
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w_reade
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Post: #12
Physics for Game Developers (O'Reilly, right?) is ok for my purposes, but I bought it more as a desktop reference for useful equations than anything else, and I'm not sure I'd want to have to actually learn the concepts from it.
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AJ Infinity
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Post: #13
Quote:Originally posted by OneSadCookie
I seem to recall that the general concensus was that the physics for game developers book wasn't worth the paper it was printed on.

As for Havok, looking at it is a purely academic exercise. They won't even give an evaluation version to anyone who isn't a major North American game developer, and the assumption is that if you're interested in Havok you can afford the price, whatever that might be, 'cos they sure aren't saying...

A more useful suggestion would be to check out ODE, which is at least free...


OSC: I use Havok. Grin But my version cames with Director MX.
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Sage
Posts: 1,482
Joined: 2002.09
Post: #14
yeah, that gamasutra article seems to help. I'll have to sort through and figure out what some of those C++ vector functions do . I'm doing my prototyping in Metal Basic before I go any further with it.
Yeah, O'Reilly book is fairly worthless, except for the basic review of linear algebra.

Scott Lembcke - Howling Moon Software
Author of Chipmunk Physics - A fast and simple rigid body physics library in C.
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AJ Infinity
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Post: #15
I actually don't have Physics for game Developers. People have recommended it to me and I just though it was good.Huh Sad :?:
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