Warp shader with bitmap controller

Started by FlynnAD, May 07, 2012, 01:31:29 pm

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FlynnAD

Does anyone have an intuitive way of controlling their warps?

I'm trying to make a curved and fanned-out portion of a striped pattern (call it a seashell if you want).

I'm using a stretched powerfractal (so basically it's stripes in the z-direction).

I'm hand-painting grayscale bitmaps in Photoshop to control where and how much I want the warp to occur, because I need specific warps in specific places. Can't leave it up to random fractal seeds. The grayscale bitmap plugs into a vector displacement with a multiplier in x-direction. That plugs into the warper. Works alright.

The issue that I'm having is that it's utterly difficult to paint precisely the warper bitmap I need.
I've made gradients in nearly every direction, and just can't wrap my head around it. This seems like it'd be naturally more warp, more white. Less warp, less white (or more black). Not quite this easy though.
For making a curved fan shape, it honestly seems like I don't need a grayscale gradient map, but the derivative of the grayscale gradient map (which is even harder to figure out). Just a gradient makes angled lines from the vertical powerfractal.

What would really help is a radial-warper, a radial vector displacement, or a rotational vector displacement node that can handle a bitmap.

Any thoughts?

Thanks,
-Matt

cyphyr

Not sure if this will help but you could try plugging the grey scale bitmaps into a displacement node and plug that into the warper. This way you could control the intensity of the warp with the displacement node.
Good luck
Richard
www.richardfraser.co.uk
https://www.facebook.com/RichardFraserVFX/
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Hetzen

I don't think a warp is going to help you. It seems like you want to scale rather than push the noise in a +/- direction. If that's the case you're going to need to build your stretched noise from blue perlins to give you control over its scale over distance, and even then, you'll be limited to working around the world origin 0,0,0.

Dune

This is the same problem I encountered when 'bending' sleepers for my railways. I can't get the 'horizontal' lines to bend according/following to the 'vertical' bends. It should be possible if you could rotate 'by condition of the initial rotation', but that's blue node stuff that eludes me. 
Curious to see if anyone replies to this thread conclusively.....

bobbystahr

Quote from: Dune on May 08, 2012, 03:26:11 am
This is the same problem I encountered when 'bending' sleepers for my railways. I can't get the 'horizontal' lines to bend according/following to the 'vertical' bends. It should be possible if you could rotate 'by condition of the initial rotation', but that's blue node stuff that eludes me. 
Curious to see if anyone replies to this thread conclusively.....

looks like another un-do-able one here.....a solution would have been nice as it's one I as well could use.....
something borrowed,
something Blue.
Ring out the Old.
Bring in the New
Bobby Stahr, Paracosmologist