Quote:
Originally Posted by Zoharl
So what the hell did you mean by r=0.159??

I mean the radius of the helix (double the distance between two points on a helix separated by 180 degrees).
Quote:
Originally Posted by Zoharl
I think I understand what you mean, but please use line (has a linear equation and goes through two points)

I did say line:
Quote:
Originally Posted by Me
Assume the difference in length of a line that goes straight from P0 to P1

Quote:
Originally Posted by Zoharl
(Again you confuse definitions of length and height. Please use my definitions above, or create it in maya, and see the attributes).

No. They are the same thing. I'm not going by whatever definitions Maya uses at all, I haven't even opened Maya regarding this problem. A geometric cylinder has a radius and a height. Said height, when transformed to a singlecurve helix, can be expressed as the length of the curve. Sorry if my interchangable use of the two has confused you.
I glanced at that thread on the physicsforum. My math skills (and thus my ability to decode that equation offered there) are not up to par to express myself in the same way. Hence I offer a layman's (or cleartext, if you will) version of my theory.
By the way: if pitch is the distance in height between each coil, I still think the solution offered in my last post is valid; just substitute Length(wound helix) with (pitch*coils), to get
length(curve) = pitch * coils + (2*pi*r*coils)
With your example of a helix curve wrapped once (1 coil) around a Cylinder, the latter having a radius of 1 meters and a height of 1000 meters:
Length(helix) = 1000m * 1 + (2 * pi * 1m * 1) = 1006,2 meters
As I mentioned, this is a simple theory. I can't offer a curve function, but you're welcome to fieldtest my formula in maya and see if you get proper results. If not, I accept that I was wrong and missed something, but until then my intuition tells me I might be on the right path.
Disclaimer:
All mentions of Helix above imply a parametric curve and not a threedimensional helicoid with any form of 'thickness'.