FOnline Engine
Current 2026.1.58-dev GitHub
Documentation Docs/en/reference/model-format/animation.md

Model Animation Directives

Generated reference. Do not edit directly. Update BuildTools/ModelFormatInterface.json, then run python BuildTools/docs_model_format.py --write.

Index Syntax Tokens Composition Assets Animation Validation Canonical JSON Guide

This page lists .fo3d directives that participate in animation selection or movement-pose composition. Effective durations, alias materialization, and script lookup are documented in Model Animation.

Directive Syntax Authoring contract Runtime effect
Anim Anim <state> <action> <ModelFile|animation-mesh> <clip|~clip|Base> Maps a state/action pair to a source animation clip. ModelFile selects the primary model source, ~ reverses playback, and Base selects the first source clip before conversion into the baked runtime rig. The first declaration for a pair is registered; model-specific lookup and substitutions are described in the canonical model-animation guide.
AnimSpeed AnimSpeed <state> <action> <positive-float> Sets authored playback speed for one mapped state/action pair. The speed multiplies runtime playback and divides the common effective duration.
AllowAnimationGeometry AllowAnimationGeometry <external-animation-file> Temporarily permits drawable geometry in one exact external Anim source while that source is repaired into a geometry-free animation file. The path resolves from the final concrete description, like an external Anim path. Validation-only: the exception is not serialized. Duplicate, unselected, duplicate-resolved, or stale exceptions fail the bake, so remove each line with the repaired source export.
AnimLayerValue AnimLayerValue <state> <action> <layer> <value> Overrides one layer value whenever the exact authored state/action pair is requested. The override is applied before redundant-call detection and model composition.
FastTransitionBone FastTransitionBone <bone> Marks a validated base-model bone for immediate transition reset when a newly attached child uses that Link bone. The next body-animation track resets transition state for the marked attachment bone.
StateAnimEqual StateAnimEqual <from-state> <to-state> Defines a one-step state-animation alias. The alias is applied once before exact animation lookup and has priority over an exact source-key entry.
ActionAnimEqual ActionAnimEqual <from-action> <to-action> Defines a one-step action-animation alias. The alias is applied once before exact animation lookup and has priority over an exact source-key entry.
DisableAnimationInterpolation DisableAnimationInterpolation Disables keyframe interpolation on the model animation controller. The registered animation controller samples without interpolation.
DisableBackwardAnim DisableBackwardAnim Selects forward locomotion context instead of backward locomotion. Movement uses the forward context and SetMoveDir also aligns look direction; the project chooses animation identifiers.
RotationBone RotationBone <bone> Selects the validated torso/body rotation bone and enables the movement overlay controller. Look and move directions may diverge; body and configured head bones receive directional rotation while movement/turn animations play on the overlay controller.

Separation from 2D root motion

These directives drive 3D skeletal clips and model composition. NextX / NextY sprite-frame offsets and movement-projected frame selection belong to Sprite Root Motion.

Start typing to search.