dragonbones 0.1.0

A pure-Dart runtime for DragonBones skeletal animation (format 5.x). Reads DragonBones Pro exports and evaluates armatures, bone timelines and mesh deformation. No Flutter dependency.

Changelog

0.1.0

First release. A pure-Dart runtime for the DragonBones 5.x skeletal animation format, with zero dependencies — it runs on a bare Dart SDK, including on the web and headless.

It evaluates armatures, bone translate/rotate/scale/all timelines, slot display and colour timelines, deform (FFD) timelines, FFD and skinned deformable meshes, IK constraints and nested child armatures, and exposes the posed result as a framework-agnostic draw list (Armature.buildDrawList()).

Verification is the point of this package: the whole runtime is diffed frame by frame against the official DragonBones runtime, across three hand-picked fixtures and all 44 demo assets from the DragonBones Unity SDK — 757,701 numeric comparisons, 0 mismatches. See the repository for the harness (tool/ground_truth/) and the raw results.

Known limitations in this release

Everything below is parsed but not evaluated, which means a file using it loads and mostly animates, then is subtly wrong rather than failing loudly:

• Animation events (EventObject) are not ported — no loopComplete / complete / frame events, so gameplay cannot yet be driven from an animation.
• IK constraint timelines are not ported. Static IK is applied and verified; animated IK weight/bend is ignored.
• Path constraints (PathConstraint) are parsed but never built.
• Surface bones have model classes only; the timeline is never created.
• SlotZIndex timeline is not ported (static z-order works).
• BoneAlpha / SlotAlpha timelines are not ported (AlphaTimelineState exists but is never instantiated; SlotColor, which carries an alpha multiplier, does work).
• Animation blend timelines (AnimationProgress, AnimationWeight, AnimationParameter) are not ported.
• Binary .dragonbones input is not supported — JSON export only.
• No object pooling, unlike upstream: Dart's GC handles it. The single biggest structural deviation, and it is not benchmarked.