how to "bend" a gradient?

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brynn
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how to "bend" a gradient?

Postby brynn » Mon Jun 15, 2009 8:25 am

Hi Friends,
Something tells me I should know how to do this, but I can't come up with it. I know that one cannot make a gradient follow a path, at least not without some distortion. But there must be some way to make this work. Here's a screen shot of what I'm trying to do.

The image is my avatar for this website, and I want to try animating it, so that it looks like a fill is in the process of being painted, like with a paint brush.

Image

I know that for an animation, I need to create a series of "snapshots", of the pink dot with its gradient "tail" as it moves along the knot. But I can't figure out how to make it turn the corner. When I get to a corner, the fully opaque, or beginning end of the pink streak will need to be going in a direction 90 degrees, or perpendicular, away from the direction the tail, or fully transparent end of the streak, is going.

Will I need to make the pink streak into a series, of say 4 or 5 pieces, so that I can arrange them as needed to show the streak as it rounds a corner? And actually, there may be places where the streak covers 2 corners (or maybe even 3, for the loops on either end of the knot). I'm not sure how long it will be, in the end.

But my main problem is that I just can't come up with any way to show the pink streak rounding the corners of the knot. Do you all have any ideas about this?

Or am I gonna have to use a raster type program, like The GIMP? Because I know you can make a gradient follow a path, although that's probably not the right terminology. I can't remember how to do it, at the moment, but I'm pretty sure it can be done.

But I really would like to stick with Inkscape, for the "snapshots", and just use GIMP to animate. If possible.

Thanks for your help :D

Grant Morrison
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Re: how to "bend" a gradient?

Postby Grant Morrison » Mon Jun 15, 2009 11:26 am

Hi Brynn. This isn't the perfect solution...but it might work if you can't come up with another solution.

I forgot to number the frames (they are layed out a'la comic book style.

The parts that pass the borders could be either masked or difference deleted. I just left it all there to help show what I mean :)

Image

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microUgly
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Re: how to "bend" a gradient?

Postby microUgly » Mon Jun 15, 2009 6:24 pm

I agree with Grants suggestion. Also, your avatar is quite small, so you're not going to notice a lack of percision--take adavantage of that ;)

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brynn
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Re: how to "bend" a gradient?

Postby brynn » Wed Jun 17, 2009 2:24 pm

That is a good idea Grant. I had thought of that, but worried that the overlapping gradients would make for uneven color as the streak winds its way through the knot.

But good point, micro. It really is very tiny at 100%, so that shouldn't even be noticeable!

Thanks for your help guys :D


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