How to create temporary colors similar to SoftTransform?

[magneto]

Hi,

When you use the SoftTransform SOP and use the Handle tool, you can see the colors in the viewport that show the soft selection. If you middle click on the node, you can see that it actually creates Cd attribute for point colors.

But how does it do it so that this attribute doesn't exist after itself? If you select another node and set its display flag, then the Cd attribute disappears.

So basically the colors only exist if you select the SoftTransform and are currently using the Handle tool.

How can I do the same to create temporary colors? Is this an event handler that triggers based on which tool is active and if the node itself is selected?

Thanks and happy new years

[edward]

The node itself is told by specific native viewport tools to cook for visualization and in those cases, it creates the Cd attribute. So basically, you can't unless you have your own custom tools and nodes.

[magneto]

Thanks Edward, so this is not possible for regular HDAs, but only using the HDK, right?

[edward]

That's correct.

[magneto]

Thanks Edward, now I know

[zarti]

hi ,

times ago i uploaded an example on official forum .

http://www.sidefx.co...ewtopic&t=22731

might help ..

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.cheers

[magneto]

Hi Zarti,

I actually checked out your file. It's pretty cool idea. The only problem is, the created point colors are not temporary like how it's done in Softpeak/Xform. But as Edward pointed out, this is only doable in HDK.

Happy new years

[edward]

What happens when you enable "Keep Visualization in Geometry" on the SoftPeak SOP?

[magneto]

If you do that, it just stores the visualized colors as point colors, permanently though

So imagine a model with some point colors, and then you add a SoftPeak, and turn on Keep Visualization in Geometry, then your previous point colors will be overwritten from that point on. But if you don't turn that on, then when you are in handle mode, you will see these colors temporarily, anything that comes after this will still have your old colors.

Would be nice if this sort of trick was available to non-HDK folks. Perhaps for H13?

[zarti]

thanks Magneto ! happy new year to you too ! =)

maybe im missing something on softtrans / softpeak ..

if you chose anything but "none" , the color attri is created or altered .

i did the same in the file i posted on sidefx ; the subnet has the "nathing" option to protect the state of things as those were .

anyway , depending on what you are doing , you may create an attrib just to visualize the values and then , if you like colors =) display it as a coloured-vectors through DisplayOptions panel .

.cheers

[magneto]

You are right, the color attribute is created but it's temporary. So to see the temporary colors, you have to be in handle mode and have "Keep Visualization in Geometry" turned off (default). Then if you select SoftPeak and middle click on it, it will show Cd attribute. If you select and middle click a node that comes after that, you will see that you don't have Cd anymore. Otherwise there would be no point in having the "Keep Visualization in Geometry" option

[riviera]

Just an idea--if you add color attribute to a guide geometry, the guide geom will be drawn using those colors (instead of the default guide color). So, you might achieve similar results by creating colored particles for all your geometry points, and use that geometry as a guide. (I hope I'm making sense here...) Not the exact same result, but might be close.

(I'm talking about the guide geometry within a SOP asset, of course )

Edited January 6, 2013 by riviera

[magneto]

Thanks riviera, that's a pretty neat idea. I knew guides were using point colors, but didn't know I could use particles

So if I am not wrong, by doing this, I will have colored points, but not a colored surface, right? Because I tried using the exact same geometry as the guide but with colors, but Houdini didn't show the guide which I assumed was because it was right on top of the actual geometry.