Alpha channel not working

[it_refplus]

Can someone explain how to use the transparency channel in V-Ray 5 ? I need to put a logo on a red background. Thanks.

[it_refplus]

As you can see here, I gave a red texture base to my cube. Then I added a blue texture with a round alpha mask. The alpha mask is working, but the red background is not showing!

[aleksandar.kasabov]

Hello it_refplus ,

In order to achieve the desired result you can use V-Ray Blend material where you can use the red material as your base material and add a coat material which has your logo and alpha mask. Please check the video recording below.

http://ftp.chaosgroup.com/support/vKjcqZV00S.mp4

[index]

Hello it_refplus ,

In order to achieve the desired result you can use V-Ray Blend material where you can use the red material as your base material and add a coat material which has your logo and alpha mask. Please check the video recording below.

http://ftp.chaosgroup.com/support/vKjcqZV00S.mp4

hi aleksandar,

ofc you can use a blend material but please add this to the todo list for v-ray 5 :
in cinema4d and in vrayforc4d 3.x you can stack material tags and blend them together by checking the "add material" check box (in the material tag)
this is documented here :
https://help.maxon.net/r23/en-us/#ht...material%20tag
--> at the bottom "Add Materials"
this is a very powerful feature because you can control the projection, scale and position of multiple materials separately in a really simple way without creating materials for a single use only !

best, index

[Makushimu]

hi aleksandar,

ofc you can use a blend material but please add this to the todo list for v-ray 5 :
in cinema4d and in vrayforc4d 3.x you can stack material tags and blend them together by checking the "add material" check box (in the material tag)
this is documented here :
https://help.maxon.net/r23/en-us/#ht...material%20tag
--> at the bottom "Add Materials"
this is a very powerful feature because you can control the projection, scale and position of multiple materials separately in a really simple way without creating materials for a single use only !

best, index

I agree.
Arranging materials should work as in Cinema 4d itself. Personally, I prefer stacking materials over one blend material. As INDEX wrote, you have more controls in a simpler way.

[index]

maybe something to add... a blend material and texture tag stacking have not really the same purpose, i think

blend materials are good for complex materials like painted, partly rusted, partly coated etc

texture tag stacking is used for placing one or multiply decals, logos etc.
being able to mix projections here is extremely powerful and you dont need to create materials for this, too.

cinema4d has a lot of really great and nifty features like this one.
not supporting them would break long established workflows and the ability to convert old files

[sirio76]

+1
I totally agree

[RwVision]

Agree also, setting up different uvw maps and uvw channel in Vray material is a bad workaround, which we are facing for many past years...

[deyan.hadzhiev]

Supporting the blending of multiple material assignments is handy, although it has less control over the blending mask and amount than the V-Ray Blend material. We have been considering to support this, but left it for future updates because it was not essential, since there is a workaround for blending materials. I agree that blending materials with multiple different projections is easier this way, so we will be looking to support this soon.

[it_refplus]

Thanks for the information. Blend material works well but I also agree with the suggestion above. One more problem I just encountered: when I add the blend material to only one polygon (flat projection) and I scale the material (a logo in my exemple), I get this strange result and it renders with multiple logos, even though I unchecked Tile. Any idea why?

[aleksandar.kasabov]

Hello it_refplus ,

This seems to be a bug and I have reported it to our developers (bug ID: VC4D-744). I will let you know once we have updates.

[it_refplus]

Thanks! This is very much appreciated.

[aleksandar.kasabov]

Hello it_refplus ,

This issue (bug ID: VC4D-744) has been fixed and it is available in V-Ray 5 for Cinema 4D - Hotfix 2. You can download and install it from here.

[index]

aleksandar.kasabov
Are the any news on the support for "adding" TextureTags with alphas to create decals?
This is an extremely powerful, essential Cinema4D feature
Vray blend materials are way inferior compared to the C4D workflow

[aleksandar.kasabov]

Hello index ,

We are still working on this and I will update this thread once we have more information.

Thank you.