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Technical support
What does Low Poly, Rigged, PBR, UV mapping and Animated mean?
Low Poly models. A polygon mesh in 3D computer graphics with a small amount of polygons (as determined by an object’s wireframe and polygon density). This usually entails designing the model in such a way that it can be used efficiently. Low poly meshes are employed in real-time applications (such as gaming), whereas high poly meshes are used in animated films and 3D visualisation. It also depends on how the model is used; AAA games can manage millions of polygons, whilst mobile devices may struggle with just a few hundred.
A character dressed in AAA game clothing may be worth 100,000 polygons. A VR avatar could have up to 70k polygons. Simple props can have tens of thousands of polygons. Large low-poly cities can have millions of polygons. Because technology is always evolving, the boundaries may shift over time.
Some pointers for making low-poly / game-ready models: if the character has hair, it should be created as a polygonal mesh (for example, hair cards) rather than a particle hair system — obviously there are exceptions (e.g. Unreal strand-based hair in .abc format). Textures should be PBR and not exceed 4K. Because some engines lack native support for two-sided shaders, single-sided planes should have thickness.
Rigged. A model is considered rigged if it meets these criteria: a logical hierarchy (FK/IK) is followed by skeleton bones and joints; object parenting and precise pivots/control nulls are used in hard-surface rigs; skinning and weighting are done correctly (simple model deformations work as expected); morphs (blend shapes) are properly set up; controls are supplied and limitations properly set; a bind frame is incorporated; transforms are reset or frozen.
PBR (Physically Based Rendering). This is more precise and consistent under all lighting circumstances since it is based on real-world values. It’s the engine that drives AAA video games and high-end renderers. The most common workflows are Specular/Glossiness and Metallic/Roughness. All core spec/gloss or metal/rough workflow textures must be provided for the model to be approved as PBR in our marketplace.
UV mapping. This is the process of projecting a 2D picture onto the surface of a 3D model for texture mapping. If your model only has basic UV mapping, you can simply pick UV mapping and leave the Unwrapped UVs option blank. You must indicate a more complex mapping if one was used. You can choose between overlapping, non-overlapping and mixed patterns. This means that the model may have basic UVs as well as unwrapped UVs, or no UVs at all.
Animated. A model is considered animated if there are keyframes and animation curves, playback has no glitches, hiccups or unexpected spikes, and any looping animation transitions smoothly.
Polygonal mesh vs. Solid (NURBS/Spline)
A model made up of polygon faces is called a polygonal mesh. Most common mesh formats: .obj, .fbx, .3ds, .dae, .stl, .max, .ma, .mb, .c4d, .blend, .lws, .lwo, .lw, .abc, .hrc, .xsi, .lxo, .lxl, .ztl, .pp2, .3b, .spp, .duf, .mud, .tb.
3ds Max, Maya, Cinema 4D, Blender, Modo, Lightwave, Zbrush, Unity, UE4, SketchUp, Softimage, DAZ Studio and Poser are some of the most common tools that support mesh type.
We do not advocate converting or importing solid NURBS formats into any of the software listed above. Imported solid models will have a large polycount, will be triangulated and may have flaws like geometry cracks or inverted normals.
Splines are used to create solid (CAD/NURBS/Spline) models. A spline is a mathematical expression that describes a curve. Most common NURBS/solid formats: .stp, .iges, .ige, .igs, .cat, .sat, .3dm, .rfa, .rvt, .dxf, .dwg, .sldprt, .sldasm, .slddrw, .catproduct, .catpart, .ipt, .asm, .cad, .jcd, .iam.
Rhino, Solidworks, Inventor, AutoCAD, Revit, TinkerCAD, Infraworks, ArchiCAD, CATIA, Fusion 360 and 3D Builder are some of the most common software packages that support this geometry type. We do not advocate or perform conversions of mesh formats into CAD software — polygonal mesh formats may import as a single object and be difficult to edit.