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Chops increasing value

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Hey,

I was hoping someone could help me out with a CHOPS set up I'm stuck on. I'm looking for a channel to continuesly increase over time at a set rate, but with added intervales? That may no make sense so I have set up a scene to decirbe it. The image below show the white line which is what I'm after. Its a mix of the red (contast increasing value) with the sine wave pink line, but only the positve values, which then get added to the red line.

Sorry if that's confussing, CHOPS is confussing!

Any help would be really apprciated!

chops_increase.png

Chops_Increase_01.hip

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There are 2 nodes that are your friend in this case. 'Slope' and 'area', these differentiate and integrate the curve.

Slope coverts the 'position" data into a velocity and the area converts back to pos.

I haven't got Houdini to hand so I'll have to explain the workflow.

 

Basically, connect your input into a slope node. Then use a limit node to clamp the negative values to 0, max can be a huge number. When you connect this output into an area node, you will find that all downward motion is replaced by flat regions.

There may be a constant you have to add as an initial value.

This works great with noise as an input too for a random forward shuffle effect.

Shout if it doesn't appear to work and I'll see if I can get a hip file later. 

JD

 

Edited by houdiniJD

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You can also achieve that kind of curve using a Count with a Constant node attached to the second input. Check out around 10 minutes into this video.

Edited by Atom

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wave chop has ramp/slope parameter which can do something similar, try gaussian wave

Edited by yesyes

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chopsIncreasing02.gif

chopsIncreasing01.gif

Here is an edit of your original file with the tweaks in place. The two yellow lines were your input curves and the blue, is the output.

By calculating the [slope] of the sine waves and the straight increasing line and returning the max of both slopes, you get an intermediate channel that is always positive. (i have added the limit node in place just in case the input curves all have a downward slope at any point).

When this is passed into a new [area] node, the 'white' curve you are looking for (values may need to be tweaked or clamped).

Hope this helps.

JD




 

 

Chops_Increase_02.hipnc

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