OBD:OBAN

ONI BINARY DATA Mtrl << Other file types >> OBDC OBAN : Object Animation switch to XML:OBAN page Overview @ Oni Stuff

Offset	Type	Raw Hex	Value	Description
0x00	res_id	01 86 00 00	134	00134-Blackvan_FB.OBAN
0x04	lev_id	01 00 00 06	3	level 3
0x08	blank[16]	00 00 00 00	0	blank filler
0x18	matrix	C2 F5 E8 3F AB D7 AA B3 EC 89 13 35 EC 89 13 35 ED 89 13 B4 C2 F5 E8 BF B1 D7 AA 33 C2 F5 E8 3F EB 89 13 B4 6B 9A 94 44 97 FD 5B C2 5D 06 DA C2	1.819999 -7.955471e-8 5.496247e-7 5.496247e-7 -1.374061e-7 -1.819999 7.955475e-8 1.819999 -1.374061e-7 1188.825561 -54.997646 -109.012428	initial position transform matrix
0x48	matrix	C2 F5 E8 3F 00 00 00 00 00 00 00 00 00 00 00 00 C2 F5 E8 3F 00 00 00 00 00 00 00 00 00 00 00 00 C2 F5 E8 3F 00 00 00 00 00 00 00 00 00 00 00 00	1.819999 0.0 0.0 0.0 1.819999 0.0 0.0 0.0 1.819999 0.0 0.0 0.0	fixed transform matrix
0x78	int16	50 00	80	unknown
0x7A	int16	F5 01	501	animation length in frames
0x7C	int16	00 00	0	unknown
0x7E	int16	65 00	10	101 keyframes in array
First keyframe (black outline)
0x00	quaternion	F4 04 35 BF 6A 19 C4 B3 CE 3C 03 B4 F3 04 35 BF	-0.7071068 -9.131584e-8 -1.222244e-7 -0.7071067	object rotation
0x10	vector	C2 F5 E8 3F AB D7 AA B3 EC 89 13 35	1188.825561 -54.997646 -109.012428	object position
0x1C	int32	00 00 00 00	0	elapsed time in frames

Transform matrices

Like all matrices in Oni, they are composed of 3 vectors defining rotation/scaling/shearing and a 4th vector defining a translation.

In the above table the 4 vectors are presented as rows (Direct 3D convention), although OpenGL and Oni use them as columns.

Affine transformations use a 4x4 matrix with 4 extra coefficients (in the presentation above, one would add one column on the right):

three projection transform coefficients (all of them are zero here); one final coefficient (always 1.0 for an affine transform matrix).

Alternatively, one can think of the 3x4 matrix as a 3x3 rotation/scaling matrix and a position vector

• Let X=(x, y, z) be the position of a vertex in the M3GM
• Let M=(m11, m21, m31; m12, m22, m32; m13, m23, m33) be the 3x3 matrix
• Let R=(m14, m24, m34) be the translation vector

Then the absolute position of the vertex in the 3D world will be: X M + R

(left multiplication is used because of the row-major notation above)

Initial transform matrix

It is used to position the object in the environment before the animation is played.

When the animation is played, they use the fixed transform matrix and a quaternion.

Fixed transform matrix

This transformation is applied before the quaternion+position transform at every keyframe.

The only transform that can't be handled by the quaternion+position is scaling/mirroring.

Thus, the fixed transform is a scaling matrix most of the time (no rotation or translation).

In the above example, the fixed transform scales the van up by 1.82 (along all three axes).

Quaternions

Those are used in Oni whenever interpolation of 3D rotation is involved (e.g., TRAM rotation)

In this case, rotation at intermediate frames is interpolated from the keyframe quaternions.

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ONI BINARY DATA
Mtrl << Other file types >> OBDC
OBAN : Object Animation
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