Mesh/Technical Overview

From Second Life Wiki
Jump to: navigation, search
Fact Sheet
Textures per Prim up to 8 texture faces per Prim
Textures per
(model) face
1
Materials per Prim Materials are currently synonym for texture faces
Vertices & Triangles 65536 vertices per texture Face

21844 triangles per Texture Face.

Note: there is a caveat here:

Whenever the triangle count of a Texture Face exceeds the limit of 21844 triangles, then the SL Importer automatically creates a new texture face, thus it automatically fixes your mesh when the triangle count per face gets too high. Actually the Importer creates as many texture faces in chunks of of up to 21844 triangles as needed for your model.

Thus when your triangle count per Texture face (in Blender triangle count per material) exceeds the limits, you will have more Texture faces in your Second Life Object than you specified in your 3D tool. But due to the limit of 8 allowed Texture Faces per Object (see above) your mesh can not have more than 8*21844 = 174752 triangles. The SL Importer will cap the exceeding amount of triangles and force this upper triangle limit on your mesh.

Objects per Upload
  • One Object containing an arbitrary amount of Mesh Prims. You will get a Linkset when rezzing the upload. You can separate the Prims within the linkset if you like (just like with any other Linkset).
  • Note that a Mesh Prim can consist of multiple unconnected "sub" meshes. Since a Mesh Prim is the smallest rezzable entity, such a mesh prim is an equivalent to a fractional sculpty from the visual impression, but has a cleanly defined Model.
  • It is up to your tool how you distinguish between separate meshes in ONE object or separate Objects.
Alpha-textures yes, but take care of the Alpha Sorting issue returning back on meshes.In general alpha textures currently create a mess. However there are some exceptions where they work well.
Normal-textures Not in first release
Specularity-textures Not in first release
Environmap-textures Not in first release
Custom Pivot (Change the center of a mesh): Not supported in first release
Mesh without physics not supported (every Object needs a physics definition). Best approach: Use simple physics meshes (A single triangle will do when you are sure that your mesh realy never needs physics)


Technical overview should include:

  • Summary of how mesh works
  • Summary of toolchain
  • Differences between existing prim system and mesh