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Use attribute to control parameter? Change thickness of sweep afterwards with attribute?

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I have a little experience with attributes and VEX now. :) I've used the color of some object to transfer color to an other object or to change pscale of other points.

But now i've come across a difficult problem, and i was wondering if there is some mysterious new thing in Houdini i don't yet yet that could help me with this.

I have animated 4 boxes and i have connected these boxes with a dashed line. The thickness of the lines is controlled by a circle which is the input of 6 sweeps. Since i want to separate the controls for the 2 middle lines (in the grey red boxes) and the 4 outside lines (in the grey network boxes), i've created two transform nodes.

While i was on the result below, i realised i wanted the thickness of the lines to be controlled by a gradient, like i've done before with color and pscale (attributetransfer), instead of with keyframing.

5c92510c45fd8_Screenshot2019-03-20at15_36_44.png.b66d2b9bf616036f90b93508e5c3ab31.png(this screenshot has copied timeshifts)

But this is a hard problem because the thickness is controlled so early in the network. 

So i wonder if there is a way i could do this? If there exists some way i could control the thickness of the line after the sweep with the gradient/color attribute i've created in the node called 'gradient'?

AttributeToParameter__.hipnc          (mentioned nodes colored red)


Would really appreciate your help. :) 


Edited by that Abstract guy
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(Sorry there was a bug in Odforce there: couldn't edit or type in that comment, had to sent) 

Anyways.. :) 

I mean something like this:


So not only over that whole line, but really from an outside source.

But i didn't know about the width attribute yet.. How would you do that? 





Edited by that Abstract guy
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it depends how exactly you have your network wired but this is how I would do it:

float baseWidth = detail('../../path_to_external_node', 'existingWidthAttribute', 0);

float widthRamp = @ptnum/@numpt;

@width = baseWidth * widthRamp;

this will read a value from an external node (it doesn't necessarily have to be a detail attrib) and multiplies it with locally generated ramp. the resulting @width I'd use as a source for polywire SOP, or sweep SOP

Edited by davpe
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