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DisplayMan generates a display list for use in nds games featuring 3d content.
It supports normals texture UV and the normalization of meshes in the case that you wish to avoid handling complex scale matrices.
This tool currently supports .dxf, .dae, .3ds, .obj, and .fbx. I recommend using FBX and it supports the most features of the 5 file formats and works in nearly every major 3d package.

Display Man v1.0 by DEElekgolo : May 01,2011
Format: DisplayMan.exe [filename] [arguments]
Arguments:
-n : export with normals
-normalize : Scale down mesh to -7 to 7 space. (Good for if you want to avoid using scale matrices)
-t ?x? : Export with texture UVs. (ex. -t 128x128) Resolutions are rounded to the nearest power of 2.
By default the file will be exported with only vertex coordinates and scale to its original size. This tool supports .dxf, .dae, .3ds, .obj, and .fbx. I recommend using .fbx as it supports the most features.Send all bugs or feature requests to [email protected]

Pics of it in use:
Normals


Texture UVs


And here is an unrealistic example.
The actual NDS hardware would not be able to take a 6k triangle mesh like this, but you get the point.