CHANGE vertex paint rgb values?

Is there something else i should be doing with the “myObj” var (or whatever i choose to call it) .. before i put in the code? i’m using it as a call js…

so when i click on the object it’s rgb goes 100% blue.

ie:

same as you put but added input rgbChanger..

        // myObj is the object to change vertex colors for
        app.ExternalInterface.setVertexPaintRGB2 = function(rgbChanger) {
            var myObj = rgbChanger;
            var vertColor = myObj.geometry.attributes.color;
            for (var i = 0; i < vertColor.count; i++) {
                vertColor.setXYZ(i, 0, 0, 1);
            }
            vertColor.needsUpdate = true;
        }

i have an onlick of the object and a var w the object’s value is plugged into the input rbChanger in the JScall.

Getting error:
ReferenceError: myObj is not defined
TypeError: myObj.geometry is undefined

i also did a simplified version with just the object actually named myObj and no changes to the code, same thing.

do i have to initialize myobj var in a script tag in the html before all this loads?

ok. got it working . thank you very much Ivan

Yeah, not to in any way say you don’t know what you’re doing, but just to clarify if you might be trying to use rgb vertex colors for actual color… Use what Ivan just said with rgb node values.

But if you’re not…then check it out…

I’m using rgb vertex colors as a sort of “masking” where I can use one material across a multitude of objects to show different images on each object dependent on their vertex color values.

I’ve got a seriously complex (yet efficient) node network going on that I’ll post here to share, if that interests you.

P.s. also, if this helps…the same thing can be done across multiple objects if you give them all uniquely named uv maps, join them all into ONE object, then so all the uv’s are combined in the joined object, THEN, separate all the objects again, as they all hold all the UV’s … And can be successfully referenced in the material that they all share, using the uv’s with math(multiply) nodes to distinguish (mask/unmask) which image nodes (or ANY node)… Is allowed to display on the designated SPECIFIC object out of the multitude of objects that share the ONE material.

Will make more sense when you see the project file(s).

This is pretty much a hack for the new ish UDIM uv’s that allow many more channels of data blender 2.83 put it in, though verge is not supporting yet

Xen Wildman wrote:

Here’s a link to the current working project:
https://tinyurl.com/y9mxeeke
Edit: Click on the sphere’s to set the values, then click the keys to change them.

that is pretty tight man. kudos!
yeah i wouldn’t be able to find it.. but there’s a huge stackoverflow convo where i’m discussing the formula with people, and one guy is adamant about the gamma node instead of the math power node, (which i had used before unsuccessfully) .. then showing him the network i used, he re-missed and said yeah.. that! .. but that was about 6-7 months ago so i’m thinking the new gamma node is probably more suited to the hack, no? .. seems you have it rocking smoothly!

also thanks for sharing your results, that’s some clever puzzle networking.
i’ll def find them useful!

EDIT: wait.. no i thought from what you said there was a new version of the gamma node.. but no that’s the SETTING (2.4 i had) of the gamma i was using before. k i’m looping back on myself here.