All values are in big endian for SMB 2, or little endian for SMB Deluxe The StageDef file is compressed using a variation of LZSS All strings are null terminated ASCII strings Try to keep things 4 byte aligned if possible (based on the specs, it seems to be built like this) Object names need to be put somewhere in the file Rotation is given in 2 bytes, ranging from 0x0000 being 0 deg, and 0xFFFF being 359.995 (rounded to 3 d.p.) deg Rotation is Z then Y then X The collision is split into a grid and is used for optimization Which triangles are tested against for collision depends on which grid tile the player is in By dividing the triangles into spatial sections, it allows the game to not test every triangle every frame The grid spans from startX, startZ to startX + stepX * stepXCount, startZ + stepZ * stepZCount startX/Z: -256, stepX/Z: 32, stepX/ZCount: 16 is known to work For clarification as to how a collision triangle is stored, the first coordinate is (X1, Y1, Z1), the second coordinate is calculated as (X1 + DX2X1, Y1 + DY2Y1, Z1) then rotated about first point by Z, then Y, then X. The third coordinate is calculated similarly, from (X1 + DX3X1, Y1 + DY3Y1, Z1), rotated by the same angles The collision grid pointers should point to different triangle lists, even if they have the same contents If not optimizing, all triangle lists can list all triangles Animations can be grouped with the animation group ID value in the collision header - This allows a single switch to trigger multiple animations Level model instances are typically not used unless duplication of a specific model is needed - for example, in Entangled Path, the LEECH_A_LOD model is duplicated, rather than having multiple of the same model in the GMA/TPL The first collision header cannot contain animation (Unless you like the idea of animating only the display of party balls/bananas, not collision) The center of rotation in the collision header may not work as one may expect. Setting the center of rotation will translate the object(s) by the negative of what was set (Effectively making the object appear to jump to 0, 0, 0 usually). Position keyframes are then used to move the object back to its desired location.