Viewerhelp:Upload Model - Level of Detail

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Level of Detail > Physics > Modifiers > Calculate weights & fees > Upload

This tab is the first step in the model upload process, in which you specify levels of detail for your model. Levels of detail (LOD) determine how the model looks at various distances. As you get farther away from a model, it renders in less detail to boost performance.

Preview your model's automatically generated levels of detail on the Level of Detail tab by selecting them from the Preview dropdown. Notice how the object's complexity is reduced at each level.

After you make selections in this tab, click the Physics tab.

Select Level of Detail

Click High, Medium, Low, or Lowest to preview and modify your model's various levels of detail (LOD). The status indicator color will show the whether your model is suitable for upload:

  • Green - No problems detected. Ready to upload.
  • Red - Too many vertices at this level of detail. Models at each level must have fewer vertices than the level above them.

Mesh

Select how you will specify your model's LOD:

  • Load from file
  • Auto-generate
  • None


Load from file: Click to manually upload .dae files for models at any level of detail. This enables you to control how your model looks at each level of detail, preserving key visual features that the automated algorithms may otherwise distort.


Auto generate: Click to generate a new model at the currently-previewed level of detail, based upon the model you uploaded.
Method   Choose a complexity level for your object, based upon a maximum number of triangles or a maximum amount of overall change in your model's shape:
  • Triangle limit: Enter the maximum number of triangles for the model at the selected level of detail. This number must not exceed the number of triangles in the LOD above it.
  • Error threshold: Increase this value to decrease the amount of detail retained during simplification. For example, setting this value to 0.1 results in a model that is simplified to 90% of the original model's accuracy.
Build Operator  

Select the method by which the number of vertices in your model is reduced.

  • Edge Collapse: Merges two vertices currently connected by an edge. Both vertices are replaced by a new, unified vertex, which is chosen to minimize error. This method does a better job of retaining the model's original shape, but can distort textures and skin weights applied to the model.
  • Half Edge Collapse: Merges two vertices currently connected by an edge. One of the two vertices is merged into the other, which remains (essentially) unchanged. This method does a better job of keeping skin weights and textures properly aligned to the model, but may result in a slightly less accurate visual shape.
Queue Mode  

Select the order in which vertices are merged.

  • Greedy: Recalculates the priority values for each neighboring edge after each simplification operation. Returns the best results, but requires the most computation and can take significant time on highly complex models.
  • Lazy: Marks the priority values of each neighboring edge as "dirty" after each simplification operation. Recomputation of costs is only done on required edges. Similar to Greedy, but optimized to give quicker and slightly less accurate results, making it useful for very complex models.
  • Independent: Performs non-overlapping sets of operations on the input geometry, resulting in hierarchies of logarithmic height. About as fast as Lazy, but calculates its results differently.
Border Mode  

Select how vertices on a geometric border are handled, that is, vertices without a full ring of triangles around them, like the edges of a flat plane.

  • Unlock: Does not treat geometric border vertices specially (default).
  • Lock: Prevents any modification to or removal of border vertices. Useful when preserving the edges of models meant to align with each other, such as blocks of terrain.
Share Tolerance  

Use this parameter to compensate for small floating point errors in your data set. It controls the point at which two vertices are considered coincident. Try increasing this number if cracks appear in your object during simplification.



None: Click to upload only a high-detail model (that is, no levels of detail). The model will not appear in Second Life when rendered at a level of detail set to None. Use this setting to improve performance and decrease resource cost for small, visually-complex models that do not need to be viewed from far away.


Generate Normals: Provides options for generating surface normals on your model, affecting its shading and appearance of "hardness" along edges between vertices.

Crease Angle  

Adjusts the smoothness of the model. Increase this value to soften the hard, "faceted" look of models with relatively few vertices.