B Splines vs. Catmull-Rom Splines

[BlindTelepath]

I was reading a short paper on the principles and general techniques of animation, and it mentioned two types of splines and the differences between them. Realizing that it was old, but also realizing that I'd never heard of Catmull-Rom splines, I was wondering if they had become outmoded, or were not useful, or what...

So what are they?

 

[Retrocide]

I was wandering a bit about Splines myself. Does the source engine use these?

 

[Ames]

No, the Source engine does not use splines.

 

[BlindTelepath]

Source doesn't use NURBS modelling, but the splines I was referring to are (by my own induction, which is probably wrong) used by 3-D design packages to gauge animations and such.

 

[Retrocide]

It's a shame, so much more could be done with NURBS.

 

[mindless_moder]

well you can model your highpoly in nurbs and then normal it onto a lowpoly object. i really dont see what nurbs can do for games.

 

[thereisaspoon]

doom3 has nurbs in their mapping program, they are way better at making smooth corners n such.

 

[Retrocide]

And hair.

 

[Mikademius]

Since the topicstarter said he read a paper on "the principles and general techniques of animation", I don't see where NURBS come in as we are talking about a different kind of curve here. (animation curves)
Catmul-Rom Splines:

The points that define a spline are known as "Control Points". One of the features of the Catmull-Rom spline is that the specified curve will pass through all of the control points - this is not true of all types of splines.

You use them every day when animating. In maya this would be a CV-curve while the EP-curve does not make control points through the spline. Then again, we're back on modeling principles.

I'm not sure actually. I guess, from a mathematical view, catmul-Rom are the curves we use by default when animating....

 

[BlindTelepath]

I'm not entirely sure I understand that... but thanks. Good to have another person to fill TDE's shoes, wish he'd show up some time.

 

[socK]

doom3 has nurbs in their mapping program, they are way better at making smooth corners n such.

It uses patches, not nurbs, but they are limited to OpenGL I think. Radiant makes curves fun, fast and easy. I love them. :[