ZBrushCentral

potential bug with polypaint and layers?

I came across something odd in my workflow, and I wonder if anyone has run into the same problem while using polypaint with layers, as well as the spray/color spray.

It is quite integral to the workflow so finding this caused massive issues, and lots of workarounds have been tried to solve it.
Any tips, tricks, recommendations, problem-solving, rubber-ducking, validation in other versions would be very welcome and much appreciated.

@floon has been kind to act as a rubber-duck with me trying to solve, or at least getting to the root of the problem, but we’re stuck. Although it seems to be something to do with the color variation.

We started noticing strange ‘hard ghosting edges’ in the painting we did on layers.
Left is showing the painting, with spray, on a layer, to the right is the same settings but not on a layer. The right is how we expect it to look on a layer too.
nOe8v7o.jpg

So I tried to test some things to work around this.


1 - no painting under, getting confetti/edges/alpha/outlining.
2 - painting with the same colour I’ll paint with after, then erase the area to ‘clean it’ of any underlying artifacts. (painting and erasing with alternate off)
3 - painting on top of the clean area, no problem right? looking nice and neat

4 - me thinking, lets try this with neon colour. paint and then erase, same steps as before
5 - getting an outline around the painting instead.

When exporting with the alpha channel (new texture from polypaint when layer is in record, no other layer visible) I got strange results again. Before I always just got the funky disco colours, but not the painted outline. Although it looked like the painted outline wasn’t in the alpha, so I thought it might have been ok anyway. alpha seemed quite clean in photoshop.

However, when the alpha is applied, the outline is still there.
And as you can see, the hard edges/artifacts follow through the export as well. So it is definitely something happening in Zbrush.

Another added thing we found was the added problem with the exported texture that anywhere it had been ‘painted and cleaned’ for the alpha to work properly, it was actually exported with a 1% alpha.
Ofc this might not seem like much in one layer, but when it starts to be more than one layer and said layer might be duplicated in photoshop too, well then it is definitely noticeable.
We’ve tried clamping the alpha, painting out/erasing, and sure, while things might work haltingly in the short run, it is something that we just cannot deal with in the long run.

just for funsies as well.
I tried painting two patches, different colours, erasing both, and then painting over them to see if that would be any different. Turns out, both had an outline of the last painted colour (neon pink) rather then the two individual colours that you can see in the previous image.

So yeah, anyone that has any info about this, or can help validate in other versions, or can try other solutions
 very much appreciated!
I’m getting a headache from all the head-against-the-wall that I’ve had over the last couple of weeks with this.

Versions tried so far with the same problem:
4r7
4r8 p2
2018.1
2019

Thank you for taking your time to read this, and sorry for the long post!

1 Like

Hi,
unfortunately zbrush is just broken as that when it comes to polyPaint on layers.
I can’t add anything to your findings, as i made the same observations and have sent in a bugReport to pixologic but i did not get a promising response from them.
Tho they are usually quite helpful.
I usually create a new layer when i want to paint something on top of an other and then i merge those but this sometimes breaks, too and you end up with a layer full of color artefacts. I don’t know why pixologic doesn’t act on that issue as it is a major bug.
Really killing all the fun of painting in zBrush. As i rely heavily on layers especially if i want to paint slight gradients and then this problem gets really annoying as i can get at a point where i have to redo a lot.

When you have a layer on record it is only considering the content of that layer.
Be it exporting a texture or masking by color/luminosity of polyPaint

I think it is on purpose to allow to export only the current layers content.
You have to turn off layer recording to export all paint.
But i handed in a featureRequest to allow for considering all paint even when layerRecording is on. As i guess a lot of people don’t know that those black (or mostly black) “textures” are a result of having layerRecording on when they export a texture from polyPaint.

I can only encourage you to hand in bugReports / featureRequests.
So they see more demand to have those problems fixed.
But so far they did not deem it “fixworthy” i guess.
Very unfortunate.

Have a nice day,
Ireneus