Anim File Format

The file format parser may be found in the open-source viewer code in the directory indra/llcharacter/llkeyframemotion.cpp LLKeyframeMotion::deserialize(LLDataPacker& dp, const LLUUID& asset_id)

Definitions

• S32 Signed 32-bit integer
• U8 Unsigned 8-bit integer (char)
• U16 Unsigned 16-bit integer
• U32 Signed 32-bit integer
• F16 16-bit float.
• F32 32-bit float.

Strings from binary unpacker take the form of a S32 for the length of the string followed by the string data. There is no null terminator. EX: cat=3cat

File organization

The anim format consists of the following header and then 0 or more recurrent blocks in sequence.

Type	Name	Values possible	Notes
U16	Version	1	//Required to be 1.
U16	Sub Version	0	//Required as 0.
S32	Base Priority	USE_MOTION_PRIORITY = -1, LOW_PRIORITY = 0, MEDIUM_PRIORITY, HIGH_PRIORITY, HIGHER_PRIORITY, HIGHEST_PRIORITY, ADDITIVE_PRIORITY = LL_CHARACTER_MAX_PRIORITY	//Needs to be UI element in anim exporter.
F32	Duration	Number secs for anim to run
String	Emote_Name	String to identify animation.	//Verify
F32	Loop In Point	Sec where loop starts
F32	Loop Out Point	Sec where loop ends
S32	Loop	True/False	//Converts to bool
F32	Ease-in duration	Secs
F32	Ease-out duration	Secs
U32	Num Hand Poses		//Treating as 0 for this example.
U32	Num Joint Motions	<= max joints of skeleton	//Number of joints that move in this anim.

Number of joints is followed by joint data. Foreach joint, read:

String	Joint name	joint to move
S32	Joint priority	See above
S32	Num Rot Keys	Number of rotation keys for this joint

Foreach rotation key on this joint:

F16	time	time (relative to start of animation)	//This becomes less accurate the longer the overall duration of the animation.
3 U16	X Y Z	The rotation on each axis

After the rotation keys are read, get the position keys.

S32

Num Pos Keys

Number of position keys for this joint

For each position key:

F16	time	time (relative to start of animation)	//This becomes less accurate the longer the overall duration of the animation.
3 U16	X Y Z	The position relative each joint's start position.	//This range is clamped to +- 5.0m

The joint keys have all be read, now it is time for constraints:

S32

Num Constraints

Number of constraints

For each constraint:

U8	chain_length	number of joints in chain.
U8	constraint_type	Types: CONSTRAINT_TYPE_POINT, CONSTRAINT_TYPE_PLANE
16bytes	source_volume	Collision volume ID string.
3 F32	source_offset X,Y,Z
16bytes	target_volume	Collision volume ID string.
3 F32	target_offset X,Y,Z
3 F32	target_direction X,Y,Z
F32	Constraint ease_in_start
F32	Constraint ease_in_stop
F32	Constraint ease_out_start
F32	Constraint ease_out_stop

See also

scripts/content_tools/anim_tool.py in the viewer source