Animation and rigs

A character plays clips - a wave, a dance, a sword swing, sitting - over its own moves. A rig is a model of your own - a creature, a machine, a windmill - held together by Bones and moved by the same clips.

Playing a clip on a character

An Animation object holds a clip. Insert one (Insert Object > Animation), pick Start from in the Inspector for one of KHIM's clips, and shape it in the animation editor. Then:

local track = player.character.body:loadAnimation(world.Wave)
track:play()
track.stopped:connect(function() print("waved") end)

Track member
play(fadeTime?, weight?, speed?)	Starts it (again from the beginning if it was playing)
stop(fadeTime?)	Stops it
adjustSpeed(speed), speed	1 as made, 0 holds still, at most 10
looped	Goes round and round
playing, length, timePosition	Read-only
stopped (also ended)	Fires when it stops or reaches its end

body:getPlayingAnimationTracks() lists what is playing. Load an Animation once and play its track again; don't load it every time.

Who sees it: a Script's clip plays for every player. A ClientScript's clip on the player's own character is sent on to everyone too; on someone else's character, only that player sees it.

KHIM's own clips

animation.preset = "dance" (or Start from in the Inspector) fills an Animation with one of KHIM's clips: wave, dance, cheer, point, salute, laugh, shrug, sit, bow, clap - the emotes players type as /e dance - and idle, walk, jump, fall, climb, to start your own moves from.

Replacing the character's moves

A character is always doing one of five moves - Idle, Walk, Jump, Fall, Climb - and each is a clip. Give it your own:

local body = player.character.body
body.walkAnimation = world.Moves.Run          -- also idleAnimation, jumpAnimation, fallAnimation, climbAnimation
body.walkAnimation = nil                      -- KHIM's own again

Your clip takes over the joints it has keys for; KHIM's keeps the rest (a run that only moves the arms still has the walk's legs). The walk plays as fast as the character moves.

The animation editor

View > Animation, or Open the animation editor in an Animation's Inspector.

• The figure shows your character in the clip's pose at the playhead. Drag a joint's dot to turn that body part - it becomes a key at the playhead. Or use the Move and Rotate handles.
• The numbers at the top right: the picked joint's X, Y and Z at the playhead. Add a key, Remove the key, and how it eases to the next key: Smooth, Linear, Constant, Ease in, Ease out, Bounce, Elastic.
• The timeline: a row per joint, a mark per key. Drag a key to move it; double-click a row to add one; right-click for its ease or to remove it.
• Play runs the clip; Looped makes it go round.
• Copy pose, Paste pose and Mirror (left and right swapped) work a whole pose at a time.

Every change is one Undo step.

A clip is text

An Animation's keyframes is plain text - a key a line, or ; between keys:

0    RightArm  0 0 0
0.3  RightArm  -160 0 20   smooth
0.6  RightArm  -120 0 40
0.9  RightArm  -160 0 20
1.2  RightArm  0 0 0

Each key is seconds joint x y z [ease]. A character's joints are Root, Torso, Head, LeftArm, RightArm, LeftLeg, RightLeg; the numbers are degrees about the character's own axes (Root is in units: 0 Root 0 -1 0 is a step lower). A joint with no keys is left to the character, so the legs walk on under a wave. Limits: 512 keys, 60 seconds, 8,192 characters.

Rigs and Bones

A Bone holds one part to another - its holder - and turns it about a point: a creature's leg, a wing, a puppet's arm, a windmill's sails.

Making one in KHIM Engine: select the holder, Ctrl-click the part that moves, then insert Bone (Insert Object > Joints). The Bone goes on the part picked last.

Bone member
holder	The part that carries it
anchor	The point it turns about, in units from its part's middle, along the part's own directions
angles	Its turn there, in degrees
offset	Moves the part from where it stood
enabled	Off: lets go

Move or turn the holder - a script, a Motion, another Bone - and the part goes with it. A part inside a boned part with no Bone of its own rides along (a hat inside a head).

-- a Script inside the dragon Model
local dragon = script.parent
dragon.Head.Bone.angles = vec3(0, 30, 0)     -- turn by hand: it looks to its left
dragon.Jaw.Bone.offset = vec3(0, -0.4, 0)    -- the jaw drops

local flap = dragon:loadAnimation(dragon.Flap)
flap:play()

A rig's clip names the rig's parts as joints - a part called "Left Wing" is LeftWing:

0    LeftWing  0 0 0
0.4  LeftWing  0 0 50
0.8  LeftWing  0 0 0

Piston:move keys move a part instead of turning it (units). Keep a rig's Animations inside the rig, and the animation editor shapes them on the rig itself.

A Spring setting (0 stiff to 1 loose) on a Bone makes its part trail behind its pose - a tail, ears, a cape.

Your own player body

Name a rig StarterCharacter, build it facing +Z, keep it in ReplicationService, and give it Animations named Idle, Walk, Jump, Fall, Climb: every player is drawn as it. See Players and characters.

From Blender

Insert > Rig from Blender (.glb) brings a whole moving model at once: each mesh object a MeshPart, each held by a Bone where its bone is, and each Blender action an Animation. In Blender, parent each piece to its bone (Ctrl+P > Bone) and export glTF Binary with Animation ticked. Skinned meshes come in at their rest pose.