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[ChrisE]

So,I've got a transform group containing Shape3Ds (TriangleArrays). The TriangleArrays contain Triangles which have vertex color information, including alpha.

When I try...

Code:

Shape3D foo = new Shape3D(triArray);
TransparencyAttributes ta = new TransparencyAttributes(TransparencyAttributes.NICEST, trans);
ta.setTransparency( transparency );
ta.setMode(BlendMode.BLENDED);
ta.setEnabled(true);
foo.getAppearance(true).setTransparencyAttributes(ta);

...I still get no change in the transparency of the object. If I override the vertex colors' alpha channel, it works. If I use a Material, it doesn't work. Interestingly, if I set the vertex colors' alpha to be opaque, it also doesn't work. So, I'm at a bit of a loss here.

Sibling Shape3Ds in the group (Line objects) do have correct transparency.

Does this have something to do with vertex colors, perhaps?

Thank you, as always, for any light you may shed on the matter.

-Chris

[ChrisE]

Update: So, explicitly disabling alpha on the vertex colors (setAlpha(-1f)) seems to help, as well as having no material attached.

[Marvin Fröhlich]

An existing vertex alpha should always override the material or TransperencyAttributes.

[ChrisE]

Fair enough. A use case I'm curious about, though, is how to handle something like gradually fading out an entire set of vertices with colors.

If I have the ghost of an astronaut, with a semi-transparent glass visor, and I want transparency on the entire model to fade in and out (while respecting the visor's "relative" transparency), how would this be accomplished?

[Marvin Fröhlich]

You would certainly not handle the visor's transparency through vertex colors, but the texture. And this works in combination with transparency attributes.

[ChrisE]

Makes sense.

[mikelizzi]

Hi,

I'm having trouble getting transparancy when I uses color alpha and assign color coordinates.   

I posted the code in the General Discussion forum.

Topic - "setting transparency on a visual object that has two colors"

This looks like the more appropriate place but I don't want to double post.  Perhaps the moderator can move my topic into this thread?