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erik_m

Ramps

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Fiddling around with COPs I ran into a problem: Say I create a ramp COP and put down lets say three different points on it. Now, what I want to do is control each of these three points' colors by other ramps. How do I go about that?

It should be really simple, as I'd guess I should be able to reference the output color components of a COP node directly. I just cannot find how anywhere...

I even tried to create a simple ramp inside of a VOP cop with a parameter picking a specific point of said ramp. What I was planning to do is then reference the output of that through pic("../vopcop", 0, 0, D_CR), pic("../vopcop", 0, 0, D_CG), pic("../vopcop", 0, 0, D_CB) onto the color swatch of the overall ramp. ...kills Houdini, so I gues that doesn't cut it :)

Any help?

Edited by erik_m

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Guest Swann

If I understand correctly your post, I don't thinkt it's possible. One point can have only one color and you want to plug multiple values into one value.

Edited by SWANN

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If I understand correctly your post, I don't thinkt it's possible. One point can have only one color and you want to plug multiple values into one value.

Sorry, I put that weired, then. I don't want to plug a ramp into the color slot, but want to pick a color from a ramp, that is then fed into the other ramp.

As if you wanted to specify three ramps, from each one only ONE color is taken at any given time. These three colors are then referenced in another ramp.

Edited by erik_m

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Guest Swann
As if you wanted to specify three ramps, from each one only ONE color is taken at any given time. These three colors are then referenced in another ramp.

Why you want to do this ? Why you cant use those three ramps instead

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Why you want to do this ? Why you cant use those three ramps instead

Well, I need a gradient ramp as a background. Over time, the values that constitute that gradient have to be animated, probably fed by data coming from a SOP. However, all within a certain color-range, say one in blueish/greenish tints ect.

To facilitate the process I thought it would be good to have that one ramp for the background and then procedurally pick colors from the other ramps, the value to be picked driven by a channel from a SOP.

I'll go to bed now and have a look at it tomorrow, I guess. This has to be a lot easier...

Edited by erik_m

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Guest Swann

You can plug it into VOPCop and output only blue and red channel. So you can animate ramp and on output have this blue/green tint. PRESS PLAY on the file.

EDIT: Or just simply use ColorCorrection before outputing it and shift it into blues/greens.

rampCop.hipnc

Edited by SWANN

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To facilitate the process I thought it would be good to have that one ramp for the background and then procedurally pick colors from the other ramps, the value to be picked driven by a channel from a SOP.

I don't know if this does what you want, but it might give you some ideas. I've made some spare ramp parameters on the Ramp COP. They're driving the color of the ramp output based on the current frame.

Check it out anyway. Just load it, go into COPs and press play.

Andy

RampTest.hipnc

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I don't know if this does what you want, but it might give you some ideas. I've made some spare ramp parameters on the Ramp COP. They're driving the color of the ramp output based on the current frame.

Check it out anyway. Just load it, go into COPs and press play.

Andy

Spot on, Andy, exactly what I was looking for! Thanks a lot for helping me out here, guys!

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