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.

Next, the following block is read for each joint with motion (as defined by Num Joint Motions above)

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

Following the number of rotation keys are the blocks of rotation data:

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

Following the rotations for this joint is the number of position keys:

S32

Num Pos Keys

Number of position keys for this joint

This is followed by the blocks of position key data. 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


 S32 num_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.
• 12bytes source_offset (A Vector3; 3 F32s)
• 16bytes target_volume //GROUND or collision_volume_id
• 12bytes target_offset (A vector3; F32s)
• 12bytes target_dir (A vector3 of F32s)
• F32 constraint ease_in_start
• F32 constraint ease_in_stop
• F32 constraint ease_out_start
• F32 constraint ease_out_stop