Why is it working with a low polygon mesh, painting is also low res. Is there a way to alter this ? It’s quit disappointing. With other 3D apps I’ve never encountered this way of working.
It’s important to understand the difference between Polypaint and Texture.
If you just start painting a mesh with no applied texture, you are Polypainting. This allows you to turn the model, paint it in real time just as you would sculpt it. When you Polypaint, you are assigning color to the actual verticies of the model, so its ability to hold detail will be dependent on resolution.
This has the benefit of letting you paint a model independently of any assigned UVs or Texture. Polypaint can be converted to an applied texture on a model with UVs, and even back into Polypaint. So it can be transferred to different versions of the same model with different UVs, and different topology. It’s very powerful and flexible.
In short, paint your model at high rez, then bake the Polypaint into a Texture to apply at low Poly.
Thanks, seeing the polys as pixels. It’s strange using a 2.5D workflow, it’s like a hybrid of Photoshop and a 3D app, gets confusing at times.
Any reason when painting materials gets blocky ? Increasing the poly count has no effect.
I’d have to see a picture of what you were talking about in regard to blocky material that isn’t fixed by increasing resolution.
The transition between material zones can be abrupt because they don’t blend in real time, although there are some render settings that affect how well material zone borders blend together in BPR. Anti-Aliasing usually takes care of the rest, although if you are using wildly different materials, it’s sometimes better to obscure the transitions.
Or you could simply be using a material with a property that highlights poly faceting. Some materials have modifier that will cause them to highlight creases, cavities, and facets.
If you would prefer to paint a texture directly and not have to bother with mesh resolution at all, you can. You would have to UV the model and assign it a texture, then you could paint the texture directly with Projection Master. Projection Master has more limitations than direct polypainting though, and you can’t paint in real time. There is a “pick up and drop” workflow that limits you to one angle at a time.
I tried subdividing as much as my ram would allow and noticed it get better. Strange that it needs much more than paint.
It shouldn’t need that much subdivision. If you give us a pic of the issue, we might be better able to advise you.
Ah yes. In this case, it’s the material zone transition issue I spoke of earlier.
This is a complicated subject. Generally in 3d it’s much easier to limit every mesh object to a single material (or “shader” in many other 3d apps) assignment per mesh object, or to obscure the transition somehow. Mixing material properties/shader assignments of complex shapes effectively on the same visible surface of a single mesh in many other 3d apps often requires using combinations of color-based specular/diffuse/bump/transparency maps. Polypaint can help to paint those. If you only assign a material on a polygon by polygon basis, it’s subject to the outline of those polygons.
If rendering in zbrush, there are a number of approaches for this, but the simplest two are detailed in the image below.
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There is a rendertime solution in Render> Render Properties> Material Blend radius, which will blur the transition between the two zones. This may be easy and effective in some situations when working purely with Polypaint.
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Otherwise, the most reliable way is to apply a texture, and paint directly on the texture instead of using polypaint. In this case, the material zone transition detail is determined by texture image size, not poly size, as you can see by the crisp material borders on the obviously low poly object. The drawback to this is if you ever want to convert those material zones back into polypaint, they will once again be bound by the mesh resolution.
So basically, it’s important to know your intended output, and establish a workflow that suits it.
Once again, thanks. It is making sense although I don’t see why it works that way.
The benefit to using polypaint, is that you aren’t locked to one set of UVs or topology. In a traditional texture workflow, once you UV a model, if you decide you want to change the geometry or UV layout, it’s not always an easy thing to change the texture to follow. Since polypaint can be baked into a texture, a texture can be converted into polypaint, and polypaint data can be projected from one mesh to another, it allows you a lot of flexibility in working between different versions of the same model. The tradeoff to this is that you must take mesh resolution into account, in addition to texture resolution.
As far as the complexities of mixing material /shader types independently of polygon/mesh boundaries, that’s just a tricky business in any 3d program. In most external renderers, you can layer shaders, but you would need to assign transparency maps to designate where you want to want the underlying shader to show through. Otherwise, you would have to use combinations of diffuse and specular maps to establish different material properties in different zones.
In Zbrush it just happens that the best way to paint blended materials is on the texture level, as polypaint doesn’t do as good of a job with material transitions, as it does with simple color.