|Channels (Rotation, Position, Scale)|
|Entity Animation Format Examples|
|Upgrade from v1.7 Beta to v1.8|
|Upgrade from v1.8 Beta to v1.10|
Animation ControllersAnimation controllers decide which animations to play when. Each controller contains a list of states that play one or more animations, each of which can be blended by a Molang expression if so desired. Controller files are stored as JSON in the animation_controllers folder Animation Controller Format:
State BlendingIf you would like there to be a cross-fade between states when transitioning, simply set "blend_transition" to the time you would like the system to take in blending between the two states. This is done as a simple lerp between the two states over the time specified. For example:
State TransitionsA state can specify any number of transition scripts, listed in order. Each transition has a target state to switch to, and a script for whether it should switch or not. For each transition in order, evaluate the script, and if it returns non-zero, switch to the specified state immediately. NOTE: Only one transition will be processed per frame.
StatesA state defines a group of animations to process (each of which can have it's own blend value). Each state has an optional variables section, listing any number of variables that referenced animations can use. Each state also has one or more animations, using the name given in the entity's definition json.
State VariablesVariables are either set by the game or by a user defined script that can be found in the entity definition json found in definitions/entity/
For Example:This defines a controller with a single state. It will create a variable `variable.ground_speed_curve` that lives on the entity only while processing the animation controller for that frame. It will take the value of `query.ground_speed`, then remap it to between 0.2 and 0.7 based on the value of `query.ground_speed` going from 0.0 to 1.0It will play one animation walk that will blend from 0.0 to 1.0 as the ground speed increases from stopped to 2.3 m/s. The remap curve can have any number of entries. The animation controller will then play the entity-referenced `wiggle_nose` animations, followed by the `walk` animation, scaling the latter by the value of `variable.ground_speed_curve`
User-Defined Script ExampleThis script will set foo to the result of the sine of query.life_time to later be used in the animation or animation controller.Note: "pre_animation" tells the script to figure out the values of those variables once a frame, before animation occurs, so that the animation can use those values in their own formulas. If a variable didn't exist, it will create a new variable and its default value will be 0.0
Channels (Rotation, Position, Scale)The engine tracks the animation of rotation, position, and scale separately. Within a channel, one or more key frames are specified at arbitrary times, in seconds, from the start of the animation. If no key frames are specified, a single key frame is created at t=0.0 and all channel data is stored within that key frame.Back to top
Entity Animation Format ExamplesThe json format for an animation is as follows. Note Matching the geometry format, units are in 1/16ths of meters.
Animation ControllerOne needs to be able to control how animations are played, when, and how they interact with other animations. to group animations While a lot of this can be managed in the entity definition `scripts/animate` section, animation controllers give you the functionality of a state machine into states and control them as a block. Animations in an animation controller state can be animation controllers themselves, allowing for arbitrarily complex animation hierarchies. Here's a sample animation controller
AnimationsAt the beginning of each frame, the skeleton is reset to its default pose from its geometry definition and then animations are applied per-channel-additively in order. Note that the channels (x, y, and z) are added separately across animations first, then converted to a transform once all animations have been cumulatively applied.
Animation data can be either raw data:By default, rotations are in degrees, in euler X-then-Y-then-Z format
or a run-time interpreted script:
Entity DefinitionIn order to define what animations an entity has, you must add both an `animations` and a `scripts/animate` section to an entity's entity definition file.
Animation HierarchyAnimations are channel based (rotation, position, or scale), and within that, they are key-framed:EntityAnimation: animation name__BoneAnimation: bone name to animation for this animation____AnimationChannel: rotation, scale, or translation to animate______KeyFrame: the value for the channel to be at, at a specific timeAll of the above concepts are described in a detailed, bottom-up approach belowBack to top
Upgrade from v1.7 Beta to v1.8There have been few changes as we clean things up based on feedback and as we push the tech along the road map.To upgrade previous scripts, you'll want to do the following steps to all of your Molang scripts in the order listed:1) entity.flags.foo --> query.foo2) entity.member.foo --> query.foo3) entity.foo --> variable.foo4) params.foo --> global.foo5) The general rule is that 'query' represents read-only values from the entity the script is running on, and 'variable' represents read-write data created by the user.6) We've adopted snake_case for all names of things. You are welcome to use upper-case letters if you wish as we are case-insensitive, however we recommend snake_case in general.7) Several variables previously set on mobs have been changed to use the query.foo format. Look through the updated list below to see what has been added and changed.Back to top
Upgrade from v1.8 Beta to v1.10The three major changes with 1.10 are- the ability to have animations reference other animations in an arbitrarily deep hierarchy.- the parameters section of animation controllers has been replaced with the `variables` section.- in the entity definition file, animation controllers are now listed in the `animations` section, and a `scriptsnimate` section has been added to define which root animations to play.The v1.8 file format is backwards-compatible with v1.10 so you don't _need_ to change anything (although we recommend refactoring your files in the spirit of v1.10 as there is a slight performance win with the new format, as well as it being simpler to understand.Back to top
Key FramesA key frame defines two values for a channel-specific transform to a specific bone at a specified time, one as time approaches the key frame time, and the second from that key frame time onwards.As such, when interpolating between two key frames, one can define the slope of the animation curve in either a continuous or discontinuous manner.
InterpolationCurrently only linear interpolation is supported. Key frame "pre" and "post" settings allow control of the interpolation curve at any key frame.
Continuous ExampleThis example spins the bone "head" around the y axis 1 rotation in 1 second.Note that because interpolation is linear, at .25 seconds the head will be rotated to 90 degrees.
Discontinuous ExampleDiscontinuous just means that there won't be a smooth transition between key frames. It is useful if you want something to happen immediately.This example scales the bone "head":1. From 0 to 0.5 seconds (in the "pre" tag), the head bone is set to its normal scale of 1 in all dimensions [X, Y, Z]2. At 0.5 seconds, the bone will instantly scale up to 2 times its normal size3. From 0.5 to 1 second ("post"), the bone will re-scale back to its normal size of scale of 1 in all dimensionsNote In the larger example above of the file format, "pre" and "post" can also be defined by a Molang expression that calculates that value at runtime, allowing you to have a mathematically defined curve instead of being purely linear.
NamesAll names: animations, bones, states, etc, must all start with a letter and contain only alphanumerics, underscore, or period. It is recommended to use names in all lower-caseBack to top
OverviewThe follows the current Minecraft JSON paradigms:- Fields should be lower-case and use underscores (no spaces)- All JSON files in the definitions directory and subtree will be read into and interpreted by the animation systemBack to top
Render ControllersThe Render Controller needs an identifier and needs to follow the format of "controller.render.
Getting StartedTo begin create a new folder named "render_controllers" in the root of the Resource Pack you want to add the new Render Controller JSON inside. Example render controllers JSON for the ocelot
Transforms- Order of operations: vertices are translated, rotated, then scaled.- Animation data is assumed to be hierarchical, and is applied to a bone by name matching the bone name in the animation data to the targeted geometry's skeleton.- Not every bone needs to be animated- You can animate bones that don't exist in the targeted geometry (missing bones are ignored).- For each of scale, rotation, position, one can set the fields individually or uniformly with a single value. For example, these are equivalent.