OBD:M3GM

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Revision as of 14:52, 7 February 2008 by Neo (talk | contribs) ("generates its own"? "ignored"? what the?!)
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ONI BINARY DATA
M3GA << Other file types >> Mtrl
M3GM : Geometry
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Overview @ Oni Stuff
OBD.png


M3gm all.gif


Offset Type Raw Hex Value Description
0x00 res_id 01 D7 00 00 215 00215-door_1_0.M3GM
0x04 lev_id 01 00 00 06 3 level 3
0x08 int32 00 00 00 00 0 unknown; maybe a runtime pointer?
0x0C link 01 DA 00 00 218 link to 00218-.PNTA (vertex XYZs)
0x10 link 01 F7 00 00 247 link to 00247-.VCRA (vertex normals)
0x14 link 01 F0 00 00 240 link to 00240-.VCRA (face normals)
0x18 link 01 ED 00 00 237 link to 00237-.TXCA (vertex UVs)
0x1C link 01 0C 01 00 268 link to 00268-.IDXA (triangle strips)
0x20 link 01 11 01 00 273 link to 00273-.IDXA (face groupings)
0x24 link 01 D8 00 00 216 link to 00216-.TXMP (texture)
0x28 link 00 00 00 00 unused unused link; never used in Oni
0x2C char[20] AD DE dead unused


Vertices
XYZ and UV coordinates are stored in parallel (same number of entries in PNTA and TXCA).
Vertex normals
The first VCRA stores the normals for every vertex (same entries as in PNTA and TXCA).
Vertex normals are used by Gouraud shading (directional lighting).
Face normals
The second VCRA stores the normals for every face (groups defined by the second IDXA).
Face normals are used for backface culling.
Triangle strips
The first IDXA lists the triangles as strips. The IDs are the ones in PNTA and IDXA.
The start of a new strip is signaled by a high bit in the ID of its first vertex.
Strips are more optimal for rendering, they are generated when authoring an M3GM.
Face groupings
The second IDXA groups the triangles into faces (oriented by the second VCRA).


ONI BINARY DATA
M3GA << Other file types >> Mtrl
M3GM : Geometry
Generic file