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Setting up a ramp with a variable time rate?

July 16, 2006 | 3:21 am

I am trying to set a ramp that moves from x to y over a unit of time, but I want the speed at which the numbers move to start slow and gradually get faster. So the ramp would be over a curved line rather than a straight line.

Thanks


July 16, 2006 | 5:09 am

There is an object. It might be [curve~] or something like that. Or you
could have a strait line call values from a lookup table or buffer~ where
the curve would be stored…


July 16, 2006 | 5:39 am

I guess I should have been more clear. I want a numeric ramp, that is based on a curved time line. I looked at curve~ and I don’t think that it could help me out. Is there an object that would be the same as curve~ but without the ~.

Andrew


July 16, 2006 | 12:38 pm

try the numeric ramp looking up a coll or table.
use the values in coll to get the curve you want.

or store both a value and a duration in coll so that you can adjust the
timing for each sequential look up…

also there may be an object like curve~ with out the ~
check all the cross refs in the helpfiles… and maybe check the ref
manual. i think there is an object thesaurus in the back.


July 16, 2006 | 1:29 pm

Have a look at lp.scampf and lp.scampi, particularly the "newStuff"
subpatcher in the .help files.

You can do a line->lp.scampf and get as many different curves as you
can dream of.

I include a little preview of one of the many sorts of curves you can
produce. Due to circumstances beyond my control, for mail-list
readers only:

Lp.scampi and lp.scampf are in the Litter Power Starter Pack, which
you can freely download from the link below.

Hope this helps,
Peter

————– http://www.bek.no/~pcastine/Litter/ ————-
Peter Castine +–> Litter Power & Litter Bundle for Jitter
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iCE: Sequencing, Recording &
Interface Building for |home | chez nous|
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July 18, 2006 | 5:55 pm

Try this– I found these a great starting point for learning more about curves: create a funbuff object, option-click it for the funbuff.help file, then double-click the object named "patcher more_interpolation." There’s an example of interpolating from a table, "shupsh," with a curve already stored in it. You could invert the readout from that curve (say, 127-n) and use that number to modify your ramp time.

Also, I’m not trignometrically minded at all, so I found page 455 of the "Max45 Tutorials and Topics" .pdf to be a real eye-opener for plotting curves mathematically. Also open Max Tutorial patch 44, "Sequencing with Detonate," and its subpatch "Another Example" for the actual objects the manual describes. I started monkeying around with some of those formulae… another great time-killer… hope this helps…

David Wright


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