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project image onto an arbitary curve

Nov 11, 2010, 18:23 (This post was last modified: Nov 11, 2010 18:24 by spiderplant0.)
Post: #1
project image onto an arbitary curve
Hi, I need to warp an image in the Y-axis direction only as if it were wrapped round a cylinder. See 'before' and 'after' attachements. Actually I need to specify an arbitary ellipse curve to project the image onto. Is there a way to do this please?
I've had a look at: Menu > Filters > Map > Map object
and: Menu > Filter > Distorts > Curve Bends
but cant get either to do what I want.
Thanks


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Nov 11, 2010, 20:45 (This post was last modified: Nov 11, 2010 21:18 by ofnuts.)
Post: #2
RE: project image onto an arbitary curve
You want a displace map (Map/Displace), using only the Y axis. The displace MAP works a bit like a bump map, except value 127 is "no move". So i you have a black to white gradient, the extremities will have a symmetrical move.

The hard part in your case it to come up with the right gradient. A little trig tells me that is looks like X-SIN(X) (where X is in radians). It's better produced by a script, but you can also approximate it by "drawing" it in the colors dialog over a linear gradient.

Now answering your questions on
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Nov 12, 2010, 22:11
Post: #3
RE: project image onto an arbitary curve
Thanks - this looks like what I was after
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