Getting Started

You can work in the browser or in Opal Desktop. Same editor, same games.

Where	How
Browser	Open https://opal-engine.com/create, sign in, and start a project. It saves to your account.
Desktop	Download Opal Desktop, then create or open a project folder on your computer. You can work offline.

Ship a playable arcade build when you're ready. Publishing needs a signed-in account in the browser editor. On Desktop, use File → Cloud Sync… to move a folder to your account first.

Using Opal

The core loop is small: open the editor, place something, press Play, save. Everything below builds on that.

First launch

1. Open the editor: Editor in the site nav (/create), or Opal Desktop.
2. In the browser, sign in — you'll land on the launcher. Pick a project or create a new one. On Desktop, create a local project or open an existing project folder.
3. In the editor top bar, confirm the Project picker shows the project you want. The launcher lets you choose an existing project, start a New Project, or import one with Open Project.
4. Open the Scenes panel in the left dock and rename the opening scene — or leave it as My Scene and keep moving. The top-bar Scene picker is a quick switch; management (create, rename, duplicate, delete, start scene ★, reorder) lives in the Scenes panel.
5. Press Play in viewport (▶ in the transport controls, center of the top bar) to confirm the scene runs. Press Stop (■) to return to editing.

That's it. Everything from here is additive: art, variables, Flow, UI, publishing.

Your work autosaves as you edit — there's no ceremony. File → Save (⌘S / Ctrl+S) forces an immediate save if you want one, but you don't need to remember it.

Projects

The Project picker in the top bar shows the active game. It controls which project's scenes, GameState, assets, and publishing metadata you're editing.

Action	Where
Switch project	Project picker → pick a project
Create project	Project picker → New project
Rename project	Project picker or launcher → rename
Delete project	Launcher / project management
Open a .opal file	File → Open Project…
Recently opened	File → Open Recent (up to 5, with scene counts)
Ship to the arcade	File → Publish to Arcade…

A project contains:

• Ordered scene list and a start scene (★ — which scene players see first; list order is authoring order, Go To Scene drives the player path)
• GameState variables — Number, True / False, Text, List, Object, with Session / Saved / Scene lifetime
• Scripts — OpalScript classes and reusable Behavior Components (opal.component(...))
• UI definitions
• The shared asset library (images, sounds, prefabs, characters, .ssb bundles)
• Art, Sound, and FX (particle) graphs (each persists on the project record)
• Publishing metadata and optional arcade listing

Scenes, assets, and input bindings are scoped to the project. Switching projects swaps all of them together.

Scenes

Every project holds one or more scenes. Use the two surfaces that look similar but do different jobs:

• Scene picker (top bar, next to the Project picker) — quick switch. Click to jump to another scene in the same project.
• Scenes panel (left dock, the Scenes workbench) — manage. This is where you create, rename, duplicate, delete, set the start scene, reorder by drag-and-drop, search, import, and see Unassigned scenes that live in storage but aren't in any project.

Typical work in the Scenes panel:

Action	How
New scene	+ New Scene
Import a scene file	Import…
Open a scene	Click the scene name
Set start scene	Click ☆ / ★ on the row (the start scene is where players spawn)
Rename / duplicate	Rename / Duplicate on the row
Delete	Delete on the row (the last scene in a project can't be deleted)
Reorder	Drag the row to a new position
Find a scene	Type in Search scenes…
Rescue an orphan	Unassigned section → Add to project

Each scene stores its own objects and hierarchy, Object Flow and Scene Flow, motion and rig data, UI references, background, and physics settings. The project owns the order; the scene owns the content.

Top-bar menus

Three menus matter most:

Menu	What lives there
File	Save, Import Scene…, Open Project… (browser) / Open Folder… (Desktop), Export Scene, Export Game, Publish to Arcade… (browser), Cloud Sync… (Desktop)
Add	Add Art (drop images straight onto the stage), Library (import to the library without placing), Sounds
Help	Tutorials & Guides, Keyboard Shortcuts, Customize Quick Actions…, Console, Problems, What's new, About Opal

If you're looking for a backup or a publish, it's in File. If you're bringing new art or sound into the game, it's in Add.

The top bar also holds the Project and Scene quick-switch pickers, the workspace tabs (Arrange / Flow ▾ / Animate ▾ / Create ▾ / Scripts / UI), and the play transport (Play in viewport / Fullscreen / Stop / Stats). Variables and Input are in the bottom shelf beside Saved; Agent opens the project assistant.

Adding content

Start from Add, then refine:

Entry	What it does
Add Art	Opens a file picker; chosen images land on the stage immediately and are added to the library
Library	Imports images into the asset library without placing them — pick them from the left asset drawer later
Sounds	Opens the Sounds manager for importing or browsing audio assets

From there:

• Open the left asset drawer to drag in images, prefabs, character assets, audio, or .ssb sprite-sequence bundles.
• Use Create ▾ → Art when you need to slice a sprite sheet or assemble frame animation before placing it.
• Use Create ▾ → Sound when a clip needs trimming, layering, normalizing, or baking before you wire it in Flow.
• Use Create ▾ → Pixels for pixel-art frames and FX for particle looks — same idea, different medium.

A useful habit: import loose art through Library, compose it in Art/Pixels/Sound, then place the baked result. Raw drops are fast but harder to reuse.

Play mode

The transport in the top bar is always visible:

Control	Action
Play in viewport (▶)	Runs the game inside the editor canvas
Fullscreen play (⛶)	Runs edge-to-edge; editor chrome hides
Stop (■)	Ends the session and restores the editor (play state is discarded)
Stats	Toggles the runtime stats overlay (frame time, draw calls, etc.)
Flow	Toggles the live graph overlay while the game is running

While playing, input, physics, animation, Flow, audio, components, and UI all run exactly as they will for players. Stop tears the play world down — nothing you changed during play is saved.

Test constantly. A one-object scene with one Flow rule is easier to fix than a large, untested level. Keep Stats or Flow on while you iterate so regressions are visible, not guessed at.

Undo and redo

Almost every edit is undoable:

• Undo: Ctrl+Z / ⌘Z
• Redo: Ctrl+Y or Ctrl+Shift+Z

What participates:

• Object transforms, inspector fields, hierarchy changes, and component edits
• Flow graph edits (scene history — adding, wiring, or moving nodes)
• Art, Sound, Pixels, and FX graph edits (each canvas keeps its own scoped history while it's active — Ctrl+Z there rewinds the canvas, not the scene)
• Motion keys and related clip edits

When you're typing inside a text field or the Scripts editor, Ctrl+Z rewinds that field, not the scene history. The toolbar ↩ Undo / ↪ Redo buttons preview whether an undo is available — they disable when there's nothing to rewind.

Saving, exporting, and backups

You don't have to think about saving, but it helps to know where it happens:

Mechanism	What it does
Autosave (browser)	Debounced writes of the active scene to your account
Save (Desktop)	Writes the project into its folder on disk. File → Save Project (⌘S / Ctrl+S)
File → Save (browser)	Flushes any pending autosave immediately
File → Cloud Sync… (Desktop)	Upload, download latest, or sync this folder with your Opal account
File → Export Scene	Downloads the active scene as opal-scene.opal
File → Export Game	Downloads the whole project as a .opal backup — all its scenes, GameState, scripts, and a union asset bundle
File → Publish to Arcade…	Ships the current build to the hosted arcade from the browser editor; Manage Arcade Listing… edits the store page without re-shipping

Before Export Game and Publish to Arcade, Opal runs a Problems check (missing covers, broken scene refs, orphan asset references, etc.). If something's wrong you'll get a dialog that lets you fix it or continue anyway — the check is advisory, not a trapdoor.

Keep a periodic Export Game even while the project lives on your account or in a Desktop folder — it's the milestone backup you can reimport with File → Open Project… (browser) or by opening the folder (Desktop).

Global variables

Open Variables in the bottom shelf to declare project-wide GameState fields. Every entry has a name, a type, a lifetime, and a default.

Type	Examples
Number	score, coins, timeLeft
True / False	hasKey, bossDefeated
Text	playerName, currentQuest
List	inventory, waveQueue
Object	player, currentTarget

Lifetime	Meaning
Session (default)	Resets when play starts; kept across Go To Scene
Saved	Remembered between plays
Scene	Resets every time a scene starts

Object Flow, Scene Flow, UI Data bindings, and scripts all read and write the same GameState. For per-object state, use the Inspector Variables card. Write from Flow with Add Counter / Set Value; read with Get Value or =GameState.score. A score label is Source → GameState in that Data bindings card.

See Variables and GameState.

Learn while editing

Open Help → Tutorials & Guides or Help → Keyboard Shortcuts to land on the hosted learning pages (/learn and the manual section on shortcuts) in a new tab. When something's broken, Help → Problems and Help → Console open their dock panels right inside the editor, next to the Scenes and asset views — no tab switch required.

Example

From an empty scene to a running game in five steps:

1. Add → Add Art — place one image on the stage.
2. Variables — create a score number variable defaulting to 0.
3. Select the art, open Object Flow, add On Tap → Add Counter (score, 1).
4. Press Play in viewport and tap the art.
5. Press Stop, then File → Export Game for a backup.

Want the number on screen? Add a Text label and bind it with Data bindings → GameState → score. UI and HUD walks that picker.

Build your first game expands this into the full coin collector.

See also

• Opal Desktop — folders, offline editing, Cloud Sync, then publish from the browser
• Variables and GameState — lifetimes, lists, object references, HUD vs Flow
• Build your first game — the shortest path from empty scene to exported game
• Editor overview — workspaces, panels, toolbar, and shortcuts in detail
• Assets and importing — import paths, the library drawer, and cutting sprites out of photos in Pixel Studio
• Pixel Studio — draw sprites, bake PNG or a .ssb
• Particle Canvas — bake custom .pfx effects in FX
• High-level scripting — copy-paste classes, then Flap
• Visual scripting — your first Flow graph
• Components guide — attaching and authoring reusable behaviors