Thanks,  Dave. 
This explains well what I have been doing! Great instructions. 
Now I just need to figure out how to adjust the wave “lengths” to create Sine wave lengths that varies throughout in the transverse direction. 
With so many calls for some waves,  one would think Adobe would have figured out a quick short cut for this!

Marj


On Aug 7, 2018, at 2:24 PM, David Clarke <[log in to unmask]> wrote:

You might want to check this out:

It's hands-on but good. I am looking around for a math talk I saw about this. I'll share it if I find it.

Dave

On Aug 7, 2018 16:08, "Britt Griswold" <[log in to unmask]> wrote:
I worked with it some more and the results with the Mesh warp are pretty finicky and sucky. It will take a lot of experimenting to get what I think you want.

You may need to go find a log chart to your as an image template, do the Zig Zag and Expand the result so you can move the waves around to match up. This is tough also because the wave form handles do not change proportionately in size and you push points together.

You can also try setting up the Zig Zag at its tightest setting, Expand the result and then use the Scaling tool and the white selection arrow to scale selected points out in one direction, repeating with one less point selected each time. That might solve the handle scaling issue.

Britt



On 8/7/18 3:51 PM, Marjorie Leggitt wrote:
Thanks Britt. 
Yep, these drawings all need to be vector files. I’ll try the Object/Distort/Mesh tool and see how that works!!


On Aug 7, 2018, at 1:47 PM, Britt Griswold <[log in to unmask]> wrote:

Yeah, that is a tricky one. There may be some specialty drafting plug-in out there that would do logarithmic scaling, but I would not hold my breath. Sounds like you want to make a slinky type wave form shape....

You might investigate the Distortion envelopes in Illustrator. You might be able take a sine wave with the Zig Zag effect, and distort parts of it with the Object/Distort/Mesh Envelope to squeeze a portion to narrower waves. I tried it, and it seemed to work visually, if not mathematically.

This might be something you could accomplish in After Effects, but that is more like animated Photoshop, not Illustrator.

Britt

On 8/7/18 3:18 PM, Karen Ackoff wrote:
Marj,

What I would do is make vertical guides spaced as required to establish wave duration. Then I’d create a serpentine path and snap the points to the vertical guides. 

Hard to describe so I hope that’s clear. 

K

>From my iPhone. 

On Aug 7, 2018, at 11:56 AM, Marjorie Leggitt <[log in to unmask]> wrote:

Hey everyone,

I have an AI question: How do you make a longitudinal wave with variable distances between the wave? The wave graduates back and forth between tight waves to move open waves.

Thank for your help.

Marj

________________________________________________

Need to leave or subscribe to the Sciart-L listserv? Follow the instructions at
http://www.gnsi.org/resources/reviews/gnsi-sciart-l-listserv

________________________________________________

Need to leave or subscribe to the Sciart-L listserv? Follow the instructions at
http://www.gnsi.org/resources/reviews/gnsi-sciart-l-listserv


-- 
_______________________________________
Britt Griswold/SED Code 600
TRAX/LUSA
NASA's Goddard Space Flight Center
Code 605 / Bldg. 34 / Rm W320M
Greenbelt, MD 20771-0001
(301) 286-3381
(301) 286-7230 FAX
[log in to unmask]
http://map.gsfc.nasa.gov

________________________________________________

Need to leave or subscribe to the Sciart-L listserv? Follow the instructions at
http://www.gnsi.org/resources/reviews/gnsi-sciart-l-listserv


________________________________________________

Need to leave or subscribe to the Sciart-L listserv? Follow the instructions at
http://www.gnsi.org/resources/reviews/gnsi-sciart-l-listserv

________________________________________________

Need to leave or subscribe to the Sciart-L listserv? Follow the instructions at
http://www.gnsi.org/resources/reviews/gnsi-sciart-l-listserv