Pyatlas

Aseprite to atlas tool — compact and metadata-aware.

Utility designed to simplify the 2D graphics production pipeline by packing sprite sheets into tight atlases with rich metadata export.

Features

• Compact atlas packing — tight layout for sprite sheets.
• Named animations — extract animations directly from the atlas.
• Layer ordering — control draw order from Aseprite.
• Frame time export — per-frame timing information.
• Meta layers — hitboxes and points computed into consumable data for your game engine.

Installation

With pipx (recommended)

pipx install .

Build a standalone binary

make build-binary

This produces a runnable binary at ./bin/atlas.

Usage

pyatlas -i <input_folder> -o <output_folder> -m <manifest_filename>

Layer Naming Syntax

Prefix	Meaning	Example
#	Animation layer	#jump
@hb	Hitbox meta layer	@hb.body
@pt	Point meta layer	@pt.origin

Animation layers (#<name>)

Layers prefixed with # are exported as animation frames. Example: #jump, #idle.

Hitbox meta layers (@hb.<name>)

The program computes the axis-aligned bounding box of non-transparent pixels for each frame. This allows defining hitboxes directly as pixel art — especially useful for per-frame hitboxes on complex characters or bosses.

Point meta layers (@pt.<name>)

The program computes the barycenter (center of mass) of all non-transparent pixels per frame. Useful for anchor points, attach points, or origin references.