The Meshes page of the Scene Settings dialog:

Naming

• Mesh/Skeleton Prefix - A prefix prepended to exported mesh and skeleton names.
• Submesh Naming - The default naming behavior for submeshes.
  • "submesh" - The word submesh will be used as the base name for submeshes.
  • Material Name - The name of the material assigned to the submesh will be used directly as the submesh's name. If that name is not unique for a particular mesh, then the material name will be used as the base name.
  • Custom - A custom name will be used as the base name for submeshes.

Mesh Settings

• Export XML Files - Indicates whether XML mesh and skeleton files should be exported.
• Export Binary Files - Indicates whether binary mesh and skeleton files should be exported.
• Byte Order - The byte ordering of data in exported binary files.
• Export Vertex Colors - Indicates whether vertex colors should be exported. Even if this is checked, vertex colors will not be exported for meshes that don't contain vertex colors.
• Format - The format of exported vertex colors.
• White - Indicates whether exported vertex colors should be forced to be white.
• Generate Edge Lists - Indicates whether edge lists are generated for meshes. This should be checked if stencil shadows are being used.
• Remove Duplicate Vertices - Indicates whether duplicate vertices should be removed. Removing duplicate vertices slows down the export process.
• Export Meshes Immediately - Indicates whether meshes should be exported as they are encountered. When disabled, the scene is collected in memory before being exported to files.
• Check for Mesh Instances - Indicates whether mesh instances should be detected. An instanced mesh is a mesh that is identical to another. Checking for instances may reduce the number of meshes exported but it slows down the export process.
• Always Create New Submeshes When Merging - Indicates whether the exporter should always create new submeshes when merging one mesh into another. If this setting is not checked, the exporter will attempt to merge submeshes into existing submeshes, only creating new submeshes as necessary.

Normal/Tangent/Binormal Settings

• Animated Normals - Indicates whether animated normals should be exported for mesh pose and morph animations. Note that this feature is only available in Ogre 1.8 and above, and is incompatible with stencil shadows.
• Generate Tangents - Indicates whether tangents should be generated and exported.
• Generate Binormals - Indicates whether binormals should be generated and exported.
• Semantics - The semantics used for the tangent and binormal vectors.
• Split Mirrored - Indicates whether to split vertices when a mirrored tangent space transition is detected.
• Split Rotated - Indicates whether to split vertices when tangent space rotates more than 90 degrees around a vertex.
• Store Parity In W - Indicates whether tangent space parity should be set in the W of a 4-component tangent.

Skeleton Settings

• Optimize Skeleton Animations - Indicates whether redundant keyframes of skeleton animations should be removed.

Automatic Level-of-Detail (LOD) Settings

• Generate LOD - Indicates whether LOD should be automatically generated for all meshes. If this is checked, automatic LOD generation settings can be overridden per object.
• Number of LOD Levels - The number of LOD levels to generate.
• Distance Between Levels - The distance between generated LOD levels.
• Reduce Each Level By - The amount by which each LOD is reduced.

Ignore Meshes