upload_model_lod - [Select Level of Detail] updated to reflect new LOD generation options

For an overview of mesh upload, see our mesh upload page. This tab is the first step in the model upload process after you have selected the high-detail model from your computer's storage. On this tab, 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. In general, the number of triangles in the combined LODs, and the scale of the object dictate the Land Impact (LI) that the object will have in-world. The fewer triangles, the lower the LI.

By default, you will have loaded a single High-LOD model and the viewer will generate the lower-LOD models for you. Preview your model's automatically generated levels of detail on the Level of Detail tab by clicking High, Medium, Low, or Lowest. Notice how the object's complexity is reduced at each level. The effectiveness of the auto-generation will vary depending on the model. You can control the generation by tweaking the parameters (for details see below). A better solution, which gives complete control to the creator, is to use custom LOD models. These are loaded either manually (see below) or automatically if they have been named in a manner that allows the viewer to detect them. This more advanced usage is described on our mesh upload page. The preview window to the right is visible from all tabs, and is resizable by clicking and dragging the lower right-hand corner of the dialogue box. The preview inside can be rotated and zoomed using the mouse, while the information displayed on the preview can be controlled by the preview controls panel. Once you have adjusted your choices on this tab, click the Physics tab.

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

• Green: No problems detected. Ready to upload.
• Amber: Does not meet the normal criteria for a LOD (typically, this means it is more complex than the higher LDO above it); this does not block the upload, however.
• Red: Too many vertices at this level of detail. Models at each level must have fewer vertices than the level above them.

Select from the Source dropdown how you will specify your model's LOD:

• Load from file: 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. If the viewer could "auto-detect" lower LOD models when it first loaded the model, these will be shown in the corresponding LOD “slots” here.
• Generate Auto: Generate a new model at the currently previewed level of detail based on the model you uploaded. This method currently defaults to using the sloppy method and tries to set a target number of triangles based upon the high LOD. This is the method applied when first selecting your model if no auto-detected LODs are found.
• Generate Precise: Uses the newer method (mesh optimiser) to construct a LOD model. This is more accurate than the “sloppy” method but will result in a more detailed model. Target triangle settings and thresholds are very loosely adhered to.
• Generate Sloppy: Uses the newer method (mesh optimiser) to construct a LOD model. The “sloppiness” relates to the accuracy of the result compared with the original. Target triangle settings and thresholds are very loosely adhered to.
• Generate Reliable: Uses the older method (GLOD) to construct a LOD model. This method is what we have been used to in the past; it gives reliable results based upon the target settings.
• For all generated LODs the following settings are available:
  • 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.
  • Note: At present, the new Mesh Optimiser options have very poor adherence to these and can result in unexpectedly high Land Impact if you do not take care to check before upload
• Use LOD above: Copy the next higher level of detail. If you set Medium, Low, and Lowest to this setting, only the model for High will be used.

Provides options for generating surface normals on your model, affecting its shading and appearance of “hardness” along edges between vertices. Note that this option will override any smoothing that was applied to the model during creation, leaving a very hard, faceted look.

Adjusts the smoothness of the model. Increase this value to soften the hard, “faceted” look of models with relatively few vertices. This applies a general “smoothing” and, like “Generate Normals,” overrides anything more specific that was defined in the model.

The preview pane will be shown to the right of the tabs and shows the model as it will appear in the selected LOD (see above) The preview controls pane allow you another means of switching the LOD display, through the dropdown menu. you can also use the Preview pane to toggle various information displays

1. Edges - draws the triangles that make up the mesh as a wireframe overlay
2. Textures - if textures were included in the model (and are thus available for upload) checking this option will display them on the preview model
3. UV Guide - if there are no textures to display you can double-check that your UV layouts are being imported properly by overlaying a checkerboard pattern
4. Physics - Displays the physics model in a manner similar to the in-world tools, it also highlights any issues (see [upload_model_physics|Physics]] for details)
5. Weights - If your model is a rigged mesh then this option (and the related joint options) can toggle whether the model is shown rigged or not ( see [upload_model_physics|Rigging]] for details)

From http://wiki.secondlife.com/wiki/Viewerhelp:Upload_Model_-_Level_of_Detail
See also Mesh and LOD