Vertex Color Alpha Channel won't work for me

Hi, I’ve set up a material that uses vertex color painting. Painting the R, G & B channels works fine, but when I hook up the alpha channel with a masked material, the painting doesn’t work. I previewed just the alpha channel in the color painting tab, and no matter what shade of grey / black I paint, the channel remains white. Is there something I’m doing wrong, or do masked materials not support the alpha channel from the vertex color node?

Thank you!

200396-vertexcolornode.jpg

200398-vertexpainting.jpg

I am also experience this same issue. It worked fine until I updated to 4.16. Now I can’t vertex paint the Alpha channels in any of my materials.

Please help us!

I am also experience this same issue. It worked fine until I updated to 4.16. Now I can’t vertex paint the Alpha channels in any of my materials.

I’m experiencing the same issue too (with 4.16.2).

Same issue here, on 4.17 alpha vertex color doesn’t work =(

same into 4.17 and 4.18… grrrr

Same issue. 4.16

When painting the alpha channel, make sure the Alpha of the Colour is changed, not just the colour itself :slight_smile:

Please see my answer below :slight_smile:

Has anyone fixed this yet?

See my reply above, it works for me :slight_smile:

Try using two materials and painting with the alpha it doesn’t work!

See attached!

This answer is really obscure.
I’m upvoting you because you fixed my problem and I’d like to clarify by saying setting paint color alpha to 0 fixed this problem for me. This was never needed in 4.15 so it’s important to know now.

Guys, just change the A parameter in the color settings to 0 (default is 1)

tried that it doesn’t work, which version are you using?

version 4.19.2

I thought I had the same problem and stumbled across this thread after a google search. However, It turns out that I overlooked a checkbox. When vertex painting there is a checkbox in the channels section where the alpha channel is off by default. I thought I’d mention it when someone else facing the same issue and overlooked this checkbox as I did.

hey all,

If this is still an issue for you you need to make sure that when painting with alpha you set the alpha on the colour picker, the colour doesent actually matter. this is what DaanRees was saying above.

change the A channel in the colour picker to 1 or 0 and the alpha painting should work.

this worked for me, hope this helps.

Это единственное, что мне помогло.
Спасибо
UE 4.25 / OSX 10.14.6