Backstage2D

A 2D animation and interactive-content engine in Rust. It starts from the Flash Pro model (stage, timeline, reusable animated symbols) and modernizes it:

• Compositions with named, blendable animations.
• Time instead of frames.
• A pure evaluated scene instead of a mutable display list.
• A crash-isolated stage process.
• Vector rendering with lyon on wgpu.

Status: pre-alpha. M1 is done: projects play live in the editor's stage and in the standalone player. M2 (edit commands, undo, crash recovery that keeps your work) is next. See the roadmap, and start with docs/. The original 2012 AS3 Backstage2D is preserved on the archive branch.

Layout

Path	Purpose
crates/backstage_core	Document model (projects, compositions, animations), time, project files, evaluate, and the mixer. No GPU or GUI dependencies.
crates/backstage_render	Draws an evaluated scene with wgpu (lyon meshes, gradients, MSAA).
crates/backstage_script	Placeholder for scripting (M6).
crates/backstage_protocol	Messages and shared-memory frames between stage and tools.
crates/backstage_stage	Editing engine process: renders the stage and streams frames. (runtime side)
crates/backstage_player	Standalone player: plays a project in its own window (winit + wgpu).
crates/backstage_tools	Editor GUI (GTK 4 + Relm4). Starts and supervises the stage. (editor side)
samples/	Sample projects. bounce.bs2d is also the file-format snapshot.
scripts/check.sh	Every check CI runs: fmt, clippy, tests, and headless smoke tests.
docs/	Vision, architecture, decision records, roadmap, dev setup, and testing.

Building

See docs/dev-setup.md for the GTK 4 dev files.

export PKG_CONFIG=/home/linuxbrew/.linuxbrew/bin/pkgconf   # Homebrew GTK on Bazzite
cargo build --workspace
cargo run -p backstage_tools     # editor; starts backstage_stage itself
cargo run -p backstage_player -- samples/bounce.bs2d   # play a project in a window
cargo run -p backstage_core --example scene_dump -- samples/bounce.bs2d 0.5s   # print a scene
scripts/check.sh                 # everything CI checks (see docs/testing.md)

Player keys: Space pauses, F / F11 toggles fullscreen, Esc or Ctrl+Q quits. --max-fps N caps the frame rate (it otherwise follows the display).

License

Copyright (c) 2026 Kevin Newman. All rights reserved. The code is public for reference only; no license is granted yet. See LICENSE.