topic Re: How to control curve color using Node Editor in Maya Animation and Rigging Forum

How to control curve color using Node Editor

gautham.chandran47 — Fri, 27 Oct 2017 04:57:55 GMT

Is there any way to control a curves color using node editor ?

I know we can change the color using drawing overrides. But how to contol it ?

My need is I want to make my controller change its color if its value is greater than zero. So it makes a visual representation of the values I tweaked ( facial UI controls )

Re: How to control curve color using Node Editor

Roland.Reyer — Fri, 27 Oct 2017 08:45:15 GMT

Yes, it is possible to connect to attributes like the override color even though they are not visible by default.

The easiest way is to use MEL:

setAttr "myNURBSCurve.overrideEnabled" 1;
connectAttr myControlNode.outColor myNURBSCurve.overrideColorRGB

Then you get this:

You can also RMB on the node with the hidden attributes and "Show all Attributes":

... and then locate the attribute and connect:

Re: How to control curve color using Node Editor

gautham.chandran47 — Fri, 27 Oct 2017 10:49:41 GMT

Thanks for the quick replay,

It worked as you said, but unfortunately I couldn't change the color

The "myControlNode" you mentioned is a layered texture ? Thats how I connected it.

If else would you please tell me which node is the "myControlNode" ?

Re: How to control curve color using Node Editor

Roland.Reyer — Fri, 27 Oct 2017 12:53:03 GMT

I wouldn't take a texture node because how do you then control the color change?

For a rig with a certain condition to change the color an expression might be the right way.

This example would change the color of the nurbsCircle1 at frame 26:

if (frame>25) {

nurbsCircle1.overrideColorR = 1;

nurbsCircle1.overrideColorG = 0;

nurbsCircle1.overrideColorB = 0;

} else {

nurbsCircle1.overrideColorR = 0;

nurbsCircle1.overrideColorG = 0;

nurbsCircle1.overrideColorB = 1;

}

You can't enter the expression editor from the Attribute Editor (like with most other attributes), you have to open it and create the expression from scratch.

Re: How to control curve color using Node Editor

gautham.chandran47 — Sat, 28 Oct 2017 04:35:50 GMT

unfortunately if doesn't seems working. I now understand i should put a texture node to control curve color, but is there any other node we can use in this situation ? the script is giving me errors.

Re: How to control curve color using Node Editor

Roland.Reyer — Mon, 30 Oct 2017 11:21:16 GMT

Yes, it won't work in the Script Editor.

This example works only in the Expression Editor:

Create a NURBS circle.

Set "Enable Overrides" ON and "Color" to "RGB"

and then in the Expression Editor:

Re: How to control curve color using Node Editor

gautham.chandran47 — Wed, 01 Nov 2017 11:49:04 GMT

I did everything as you mentioned and the expressions didn't give any errors but I cant find the out put. The color is not changing..

Any idea why ?

Could you please post the work file for a reference maybe ?

I dont know what I'm doing wrong.

Re: How to control curve color using Node Editor

gautham.chandran47 — Sat, 04 Nov 2017 07:14:47 GMT

When i combined the both methods you mentioned it came out alive ...

Re: How to control curve color using Node Editor

gautham.chandran47 — Sat, 04 Nov 2017 07:27:07 GMT

Thanks a lot . as you mentioned I created a "layerd textured node" and curve and renamed it accordingly;

setAttr "myNURBSCurve.overrideEnabled" 1;
connectAttr myControlNode.outColor myNURBSCurve.overrideColorRGB

You were right about using a texture node to control curve color,

so I changed the "color" mode from "index" to "RGB" in the drawing overrides on attribute editor.

And after that I could easily change the color of the curve through the layered texture's properties.

I can even animate it.