Opacity problems on polygon selection and multiple materials

[Gpix]

Hello everyone,

well, I just stumpled into another opacity problem, I don't get wrapped my head around. After a long time of troubleshooting, I have no idea what I am doing wrong.

I have modelled a polygon object, and made 3 different polygon-selection. Each selection gets a different material.

As the final step, I would like to put on a 4th selection a glossy material, with an imagetexture on top of it of a brand name for example

In my logical thinking, I should see the underlying material of the other selection through the black parts of the opacity map, and only the letters should be opaque. (Like adding an Add-Layermethod in Photoshop)

But, here is the result: There is just nothing around the letters and it makes the polygon-selection invisible, and I can see into the object.

Also: I discovered, when I try to put a brand labeling on a transparent material (like a transparent packaging box) on a polygon selection, the refraction of the material gets faulty on just that polygon. As soon as I delete the texture on the selection, it works physically correct again.


Please, can somebody tell me, how I achieve to put a label on a with selections textures object and only get the stanced out letter, and still see my materials under it?

I attached a test file to this post.

OpacityProblemTestscene.zip

Opacity Problem Testscene

(161.65 KiB) Downloaded 101 times

Thank you in advance and happy holidays!

Best regards
Sven

[aoktar]

Here's the problem, our material stacking is not supporting the polygon selection. Divide your mesh to two parts and try. Or use texture mixing for coloring the stencil without breaking it.

[Gpix]

Hey Ahmet,

thank you for your reply,

okay, I will give it a try.

But as I understand, I have no possibility to put a label with opacity over two different materials?

I can only have one material applied to the object without a selection, than I can put one material with opacity on it, and it will work. But as soon as I have two base aterials, and I want to have a label overlapping these both, it won't work? So I have to make the two-tone base texture, as one material generated inside a octane shader?

Seems to be a little too complicated to have to do this workflow for a simple (and important) task like putting a brand label anywhere on a object without thinking about where and how many base pbr-materials there are already applied.
Positioning just a fonttype is much more convenient and easier, if one can use cinema 4d texture move tool and not a texture projection map.

I love octane, don't get me wrong, but these are these little things that interrupts the creativity process and frustrates me some times a little too much.

[aoktar]

This little things are little for users, but big enough for me. Otherwise I'd implement that but it's very hard to do without exploding the my brain. This is hard because of design differences between Octane vs. C4D
See this is possible as you see

[Gpix]

Hi Ahmet,

I totally understand you, and I am in absolute awe as always, that you keep as greedy and needy cinema 4d users up-to-date with that plugin.
You know, I totally respect your work, and especially the amount you have to research into, when developing these "little" things into the plugin!
Seeing all the time also the coder side of your work, makes me always hesitate when I discover a hurdle. I always try to find the octane adaquate solution first and not bother the forum with any maybe "simple" question.

Thank you, for giving me the hint how to do a possible workaround for that specific problem! It works with that workaround. And with a little fiddling, I can implement also a third color. So thank you sir so much!

Best regards
Sven