Decal on bottle in modo

[Danielhruby]

I am trying to do a simple decal on a bottle. I am not sure if I should be using a Layered Vrray material or a Blended Material. I tried to hunt through the forum and found similar questions. I learned that the Layered material will prevent my from having a matte finish on the label and a glossy finish on the glass. So, is it a blended material? I have tried to set up my scene and still cant get it to work. If anyone can rig this up for me, I would appreciate the lesson!


Here is what I have so far...

https://www.dropbox.com/sh/8psn4u4dc...7rs1hTPOa?dl=0


Thanks

[Danielhruby]

Here is where I have it so far. Got the label to appear, but no diffuse color is coming through.

[vladimir.nedev]

There is no point in connecting the decal alpha to the "Diffuse color" alpha plug on the V-Ray material, it won't do anything.

You should either put "Decal Alpha" above the V-Ray Blend Material and set its effect to vblend Amount 1 from the V-Ray Blend Material effects
OR
connect it in the Schematic, similar to how you've done it in the screenshot, but use the Texture Color output to connect to Amount 1.
There are two reasons for this. First the texture is a simple black and white image, so the Texture Alpha output will be all white.
And second, the Amount 1 plug is a color, if you connect only a scalar input to it, only the red channel gets connected.

Greetings,
Vladimir Nedev

[Danielhruby]

I tried both but no luck....

Seems like I should just be able to have the decal material above the Bottle material and drop the alpha image ontop of the Decal material to act as a layer mask. But probably VRay doesn't work that way. It would also be nice if the decal could be recognized if in effect is set to modo's Stencil mode. I have saved the file again if anyone is able to connect it up right for me to see.

[vladimir.nedev]

Seems like I should just be able to have the decal material above the Bottle material and drop the alpha image ontop of the Decal material to act as a layer mask. But probably VRay doesn't work that way.

That could work also, but might have issues, layer masks will blend only between the texture effects within a material, they are not true material blending.
I've explained it in numerous posts, like this one : https://forums.chaosgroup.com/forum/v-ray-for-modo/v-ray-for-modo-problems/73685-blending-material-group?p=816147#post816147

It would also be nice if the decal could be recognized if in effect is set to modo's Stencil mode.

Stencil is something completely different - it's 0/1 transparency for the whole surface and it doesn't work with V-Ray materials at the moment, although this is logged as an issue.
Still its purpose is different from what you want.

I have saved the file again if anyone is able to connect it up right for me to see.

Actually the file I downloaded yesterday from your dropbox was working.

You seem to have it setup correctly in the screen-shot also. Note that adding/removing schematic connections is not updated in RT, you have to restart it.
Also note that there is no point in both specifying a texture effect and making a Schematic connection.
For the texures of the V-Ray Blend sub-materials you always have to use the Schematic, their "effect" in the Shader Tree is ignored.

Greetings,
Vladimir Nedev

[vladimir.nedev]

Actually you should have the blend material in "energy conserving" mode and the blend amount color should be all black, as shown in the screen-shot.
This is because the decal texture is in "reset" mode, so it gets blended with whatever is below it.

I am attaching the fixed scene.

In your drop-box you have the original 3ds Max scene, it's setup without a blend material.
You can actually export that to .vrscene and import it in Modo, but the importer has a bug in this case - you have to additionally set the refraction color of the V-Ray material to white.

Greetings,
Vladimir Nedev

[boyan]

Hey, Daniel,

I can recommend you to use specific geometries for the labels, it is more flexible and fast solution. You can use "Selection tag" for the label polygons as well and assign a mask to tag. V-Ray 2-sided material is also can be used instead of blend.

Check my version with newly added label. You should update the JPEG images with PNG files.



Cheers,

[Danielhruby]

Thank you Vlad and Boyan.

Lots of moving parts, but I can see now the solution. It is a fairly common task and I found it difficult to find a good example out there.



Boyan,

Yes, that was an approach I considered. The problem for me is that I was going to have to "VRayify" a scene with dozens of liquor bottles that already use the single surface with layered clip map on them for the labels. It was going to be tedious to model all of the little labels. Some bottles have several labels on them, too. After doing all of this, I would definitely need a drink! LOL.

Cheers, Gentlemen!

[boyan]

Howdy, Daniel,

If you don't like modeling variant, you can use "Selection Set". Stencil as a texture layer effect also works but you need both (Modo default and V-Ray) to use group mask with polygon selection tag.

Cheers,