How to download the mesh land impact in Second Life while keeping in Medium and Low the quality of an item is the key question for all content creators, specially for sellers that want to give their customers a good and efficient product (efficient balance between LODs and Physics at min. land impact possible).
In game design, the Lower Poly is your model, the most homogeneous is its mesh and the better compacted is its texture, the most efficient at render cost. When you want to design for Second Life, you have to consider these 3 things plus understanding SL’s Mesh Uploader. Some years has pass since they allowed creators to upload their own items, but there’s not yet too much information from Linden Labs about how it works properly their uploader. This forces the community to test, with not really clear answers.
After reading the topic UV Unwrapping increase Land Impact, where users debate about if type of shading and UV unwrap method have relevance or not to download Land Impact, I have run some tests with an organic mesh, a tear I’ve made, with the following questions in mind:
- Smooth shaded models give less, more or equal land impact (LI) than flat ones?
- The UV maps with more islands increase LI? (UV methods used: UV unwrap with Mirror Mod -generates 2 overlayed islands-, UV unwrap -1 island-, Smart UV Projection -multiple islands-)
- How affects subdivision level? (Subsuf 1 and 3)
All tests run with default LODs. Blender version is 2.72 and Second Life’s Viewer used was Firestorm.
SMOOTH VS. FLAT SHADING
Observation: In the major models uploaded, smooth wins versus flat. Just in very LP meshes, and depending of the unwrapping, smooth and flat can give same LI as result.
Conclusion: Smooth shading is more effective to reduce LI than flat shading.
UNWRAPPING METHOD AFFECTS LAND IMPACT
Observation: There’s a difference between the 3 methods used.
- When tear model uses flat shading, UV unwrap using Mirror Mod is the most effective, followed by Smart UV Projection and UV unwrap
- When tear model uses smooth shading, the better method is Smart UV Projection, followed by UV unwrap using Mirror Mod and UV unwrap
Conclusion: The UV method used to unwrap a model affects LI.
HOW AFFECTS LEVEL OF SUBSUF TO SHADING AND UNWRAPPING
- At Subsurf of 1:
- In LI, The only difference is in tear with smooth shading and Smart UV Projection, giving a lower impact. For the rest, there’s no difference using smooth or flat shading with any of the 3 unwrapping methods used
- In Dowload, different shading and unwrapping methods seem to affect
- Physics have same value than LI in tears with smooth and flat shading
- At Subsurf of 3:
- We see a clear difference in the models LI related to shading and unwrap
- In Dowload, flat shading and unwrapping methods used don’t seem to affect while yes with smooth shading
- Physics have same value than LI in tears with smooth shading, while in flat shading there’s a difference
Conclusion: When level of Subsuf increases, the difference between shading and unwrapping methods is more obvious.
As one can see, the method used to unwrap and choosing between applying smooth or flat shading is important related to Subsuf level.
Click on any picture to open the gallery.
Subsurf of 1, Flat Shading
Subsurf of 1, Smooth Shading
Subsurf of 3, Flat Shading
Subsurf of 3, Smooth Shading