OTOY Forums

Notiusweb wrote: With the 'Normal Map' issue, does anyone know why the shadows, when Normal is 2 in these situations, are so pixelated?

Generally shading computations involving normal maps assume that directional vectors represented by normal map have unit length. When not results are unpredictable and renderer-specific. I don't know how scaling is performed in this case in Octane but generally any scaling of normal maps is silly idea.

One more for the list: Weird triangles on V7:



Note that this is with the default blank material, so it's not a conversion/normal map issue.

DrHemulen wrote:One more for the list: Weird triangles on V7:



Note that this is with the default blank material, so it's not a conversion/normal map issue.

Daz3d seemed to have optimized G3F for Iray which applies some subdivision by default when rendering.

G3F has by default LESS points, vertices, polygons than G2F.

Also note that some G3F V7 morphs are HD.


Basic recommendation:

Raise subdivision level to 3 so you are working with 1'000'000 points and not less than 100'000.

linvanchene wrote:

DrHemulen wrote:One more for the list: Weird triangles on V7:

Daz3d seemed to have optimized G3F for Iray which applies some subdivision by default when rendering.

Even DAZ cannot be so evil We had discussion (http://www.daz3d.com/forums/viewthread/58050/) where MallenLane, creator of G3, explained some of decisions behind the new mesh. Basically yes, it has to be subdivided when you need better details and one is expected to use HD morphs for that (and buy them from the store as general users do not have tools to make them ), but it has nothing with iray.

This issue is all about how normals are interpolated along triangle's edges when low-poly quad mesh is triangulated before sending it to renderer.

As you can see, iray may be even more weird:

Have you tried that with displacement maps? (I'll dump bump into displacement, and scale it accordingly.)

Also... did you try smoothing? I do that sometimes with accordioned hip or arm bends.

Feature Request:

Highlight empty Image Fields in bright red, as well as the materials in the Octane Material List.

It can be pretty annoying if something got left out or lost in a scene, and its pretty hunt and peck when something is missing. (Recent Normal Map issues merely highlight this issue.) I noticed that when I build a character skin with different face/lip maps, that the lips will have missing Spec or even Bump maps. I don't care why something is missing, but missing isn't good for rendering.

asennov wrote:Even DAZ cannot be so evil We had discussion (http://www.daz3d.com/forums/viewthread/58050/) where MallenLane, creator of G3, explained some of decisions behind the new mesh. Basically yes, it has to be subdivided when you need better details and one is expected to use HD morphs for that (and buy them from the store as general users do not have tools to make them ), but it has nothing with iray.

I wonder how far we can get with using displacement maps instead of HD morphs? That was the way I was thinking of going... sculpt hi-res shape and export lo-res version as morph and a displacement map to capture the higher levels of detail.

DrHemulen wrote:I wonder how far we can get with using displacement maps instead of HD morphs?

Displacement maps have some limitations:
1. they work along the surface normal only while morph may move vertices in any direction. So with morph you can make say a curly horns and not with the displacement
2. like any texture they follow UV maps and UVs have distortions, different resolutions in different material zones etc. HD morphs also suffer from similar problems as mesh vertices are not distributed evenly - face has more, legs have less. And they tried to target this problem in G3 mesh.
3. Displacement maps are textures so usual problems with resolution (so need for HDR) and VRAM will apply

Edit:
4. Displacement maps make handling of ray tracing acceleration structures more complex. That's why Octane has it only since V2 and Iray has it only in form of vertex displacement of subdivided mesh.

One more: I wrote this from the POV of raytracer renderer like Octane or iray, but REYES handles displacement much easier and displacement map over the lower-poly mesh is how they do it in 'big' CG and Renderman

Hydra wrote:Also... did you try smoothing? I do that sometimes with accordioned hip or arm bends.

With this 'issue' increasing the subd level as linvanchene suggested is legit method. A bit 'brute force' thou Smoothing cannot help here as bad things happen after all modifiers got applied - when triangulation is performed. Studio uses naive method of triangulation, it just split quad in two triangles and no care is taken about mesh curvature at this point so with low-poly meshes such issues are inevitable.