Advanced LOD Techniques

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This page details a number of LOD techniques which are not in themselves new capabilities, but rather which make inventive use of existing capabilities.

Texture Atlas at low LOD

Use of mesh-table LOD with LM.txt

Mesh-table LOD is an entirely separate concept from the self-contained LOD present in LM.txt files. You should not attempt to configure the LM.txt transition distances using the "mesh-table-lod-transition-distances" tag. It is, however, possible to combine the effects.

Consider the following LOD structure:

  • Mesh-table LOD 0
    • LM.txt LOD 0
    • LM.txt LOD 1
    • LM.txt LOD 2
  • Mesh-table LOD 1
    • IM
  • Mesh-table LOD 2
    • IM

In this scenario, you effectively offer 5 LOD levels. There are 3 mesh-table LOD entries, but the top LOD is itself an LM.txt file with additional "sub-LODs".

Using this approach allows you to use features that are exclusive to the LM.txt file format, such as attachment point LOD control and animation shared across LOD levels, while benefiting from the efficiencies of mesh-table LOD (such as fully-disabled animation and suitability for mesh stitching) at lower detail levels.

Since the mesh-table LOD is independent of and takes precedence over the LM.txt file LOD, you must ensure that the LOD distances between the two systems are appropriately configured to show each of the LM.txt file LOD meshes before switching to the next mesh-table LOD. If you get this wrong, you may find that the next mesh-table LOD kicks in before the LM mesh has reached low detail.

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