Dan, you can get close with a ease-in-ease-out function, aka easy-ease in AE.
Check out : http://abstrakt.vade.info/?p=132 the javascript in the Max/MSP patch potentially be of help, while it has some extra junk for Max/MSP, the basic math is in there, implemented in a similar way as to what you want. On Mar 19, 2010, at 4:42 PM, Dan Winckler wrote: > Thanks, Troy! I don't need to draw the curve, actually -- I'm just using it > to scale incoming data. Specifically, I'm taking an incoming float number > between 0. and 1.0 that is a linear scaling of pitch and reshaping it. > > If you're curious, yes, this is related to my previous post about > pitch-tracking. Specifically, I'm doing the pitch-tracking in Max/MSP with > the fiddle~ object and sending the resulting pitch and amplitude, scaled, to > a QC comp that uses the pitch to control the hue of a gradient. > > Even more specifically, it's something I put together for Wiley Wiggins, who > is doing visuals with The Octopus Project in Hexadecagon, which is a free > show this evening in Austin, TX. "Music for eight-channel sound and > eight-channel video performed live in the round. Awesome!" > http://www.theoctopusproject.com/hxdx.html Wish I could be there but, alas, > I'm in NYC. > > cheers, > dan > > > > On Mar 19, 2010, at 4:27 PM, Troy Koelling wrote: > >> If those circles are control points, I'd probably guess this is a cubic >> spline. CoreGraphics has the ability to draw that if you need to. >> >> This is a pretty good rundown: >> http://cocoawithlove.com/2008/07/coregraphics-curves-and-lines-sample.html >> >> On Mar 19, 2010, at 1:15 PM, Chris Wood wrote: >> >>> See also gaussian curve/bell curve/s-curve... Although of course that was a >>> straight spline curve in the first pic. Splines will give you what you >>> want, but maybe not in the most simple way. >>> >>> Chris >>> >>> >>> On 19 Mar 2010, at 19:52, Dan Winckler wrote: >>> >>>> Thanks, Tom and Jon! I remembered Grapher earlier today and it was a big >>>> help, even though polynomial curves are not among its examples (sure beats >>>> my old TI-82). Now to tweak the numbers until they give me the shape I >>>> need. Additional help still welcome if offered. :) >>>> >>>> best, >>>> dan >>>> >>>> >>>> >>>> <Screen shot 2010-03-19 at 3.49.57 PM.png> >>>> >>>> >>>> On Mar 19, 2010, at 3:40 PM, Jon Pugh wrote: >>>> >>>>> At 3:14 PM -0400 3/19/10, Dan Winckler wrote: >>>>>> What do you call a curve like the one in the attached image? Rather, >>>>>> what's the mathematical term for the equation that produces such a >>>>>> double curve. I am trying to scale an incoming float number (0.0 1.0) >>>>>> so that it changes more quickly in the middle of the range (~0.2 - 0.8) >>>>>> than at the top and bottom (~ 0.0 - 0.2, 0.8 - 1.0). Right now I've got >>>>>> exponential scaling, which works for the bottom of the range but not the >>>>>> top. >>>>> >>>>> This is a curve produced by a polynomial equation. I recommend opening >>>>> the application Grapher, which came with your Mac, and entering this >>>>> equation: x = y^3+y^2+y >>>>> >>>>> This will give you a curve approximating the one you've drawn. Then you >>>>> can play with adding numbers before the various terms (i.e. 3y^3, etc) to >>>>> change the shape of the curve. >>>>> >>>>> Good luck. >>>>> >>>>> Jon >>>>> _______________________________________________ >>>>> Do not post admin requests to the list. They will be ignored. >>>>> Quartzcomposer-dev mailing list ([email protected]) >>>>> Help/Unsubscribe/Update your Subscription: >>>>> http://lists.apple.com/mailman/options/quartzcomposer-dev/dan%40danwinckler.com >>>>> >>>>> This email sent to [email protected] >>>> >>>> _______________________________________________ >>>> Do not post admin requests to the list. They will be ignored. >>>> Quartzcomposer-dev mailing list ([email protected]) >>>> Help/Unsubscribe/Update your Subscription: >>>> http://lists.apple.com/mailman/options/quartzcomposer-dev/psonice%40gmail.com >>>> >>>> This email sent to [email protected] >>> >>> _______________________________________________ >>> Do not post admin requests to the list. They will be ignored. >>> Quartzcomposer-dev mailing list ([email protected]) >>> Help/Unsubscribe/Update your Subscription: >>> http://lists.apple.com/mailman/options/quartzcomposer-dev/tkoelling%40apple.com >>> >>> This email sent to [email protected] >> > > _______________________________________________ > Do not post admin requests to the list. They will be ignored. > Quartzcomposer-dev mailing list ([email protected]) > Help/Unsubscribe/Update your Subscription: > http://lists.apple.com/mailman/options/quartzcomposer-dev/doktorp%40mac.com > > This email sent to [email protected] _______________________________________________ Do not post admin requests to the list. They will be ignored. Quartzcomposer-dev mailing list ([email protected]) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/quartzcomposer-dev/archive%40mail-archive.com This email sent to [email protected]
