This is a simplified checklist for artists submitting 3D models to StemCell in 3ds Max V-Ray. We know that the StemCell Specification contains a lot of information, but following these guidelines will bring you one step closer to having a StemCell certified asset.
Scene/File Setup
- System and Display Units should be set to Centimeters; model is real-world scale
- All Geometry is under one group (No object linking), and one Layer is named after the scene
- No Cameras, Lights, or anything other than the model’s geometry and materials, should be in the scene
- Scene is set to correct Renderer
- All nodes for objects, groups, layers, and materials are uniquely named (no duplicate naming)
- All textures should be placed in their own folder titled ‘Textures’
- All textures should have Relative Paths
Geometry
- No Isolated Vertices, Overlapping Vertices, or Overlapping Faces
- Xforms, Transform, and Scale are reset, and the model’s overall xform should have its center pivot centered on the origin of the XY Plane and touch the lowest Z point
- No visible faceting, texture stretching, visible seams, or flipped normals; all objects must contain at least one smoothing group
- All modifiers besides Edit Poly and Turbosmooth must be collapsed
- UVs should be Non-overlapping (some exceptions), and are logically unwrapped to Maximize Texel Density
Textures
- Textures are 8-Bit, RGB, and in TGA or PNG format
- Textures are square resolution and same resolution is used within a given texture set
- All Base maps are included for DCC and RT (if applicable)
- Textures follow naming conventions and are plugged into correct slots
- Textures Blur values are set to .01
- Texture map contribution is set to 100%
- Texture Gamma for all maps is set correctly (Automatic or Override 1.0)
Materials
- All Geometry has a material applied of the correct type
- Materials do not contain any maps or procedural nodes that are not listed in the Stemcell Specifications
- Normal Bump node must be used for all Normal Maps
- hGlossiness should be linked to rGlossiness, Fresnel Reflections should be enabled, and the BRDF should be set to Microfacet GTR(GGX)
- If Refraction is used, all settings should be correctly configured
- If a Blend is used, all settings and maps should be correctly configured