Play-in-editor

Play-in-editor (PIE) runs your game as a real process and streams its frames into the editor, so you can play, inspect, and live-edit a running build without leaving jackdaw. The game runs in its own process, so a crash takes down the game, not the editor.

PIE keeps two surfaces strictly separate:

• The Game panel is a pure monitor of the running game’s frame.
• The Viewport is always an editing surface for the authored scene. It never composites the game frame over your scene.

What you need

PIE launches your game from its run configurations. A project that plays in the editor has at least one runnable config in its jackdaw.toml, and the config that streams into the editor builds with the pie feature. See Scene Management for where project config lives, and your game crate’s jackdaw.toml for the configs themselves.

How many configs you define is up to your game. Some games run a single process; others split into several that you launch together. PIE treats each launched process as an instance and streams the focused one.

Open the Game panel before you start. It docks in the bottom dock area next to Assets.

Launching

The play controls header carries Play, Pause, Stop, and Reload, plus a window-mode button that reads Embedded or Windowed. The window-mode button sets the mode for the next launch.

• Embedded (default): no separate game window opens. The game renders off-screen and streams into the Game panel at full frame rate. This is the mode you want for input capture and picking.
• Windowed: the game opens its own OS window. The Game panel still mirrors the active in-game camera once one exists, but menus do not stream and input capture is not offered.

Hit Play to launch. The Game panel starts streaming immediately, beginning with whatever the game shows first (often a menu or title screen). The outliner shows a LIVE badge with the running instance’s name.

When more than one instance is running, the instance picker in the outliner header switches which one the Game panel and Live tree follow.

Playing the game

The Game panel header has a Play | Select mode bar.

In Play mode, click inside the panel to engage input capture (or use the Play Input header button). While captured:

• Keyboard and mouse forward to the game. WASD, mouse-look, scroll, clicks, and typing all reach it.
• Editor keybinds are suppressed. Tool keys and Ctrl+S go to the game, not the editor.
• A Playing, Shift+Esc to release chip shows, and the panel border takes the capture accent.

Plain Esc forwards to the game (so the in-game menu still opens). Press Shift+Esc to release capture and return control to the editor. Capture also releases on its own if you stop the game, switch instances, click away to another application, or close the panel, and any keys you were holding are released so nothing stays stuck down.

Selecting entities from the frame

Switch the mode bar to Select. Game input stops, and the cursor becomes a picker over the streamed frame.

• Click an object in the frame to select it. The selection appears in the outliner’s Live tab and the inspector shows its live values.
• Picking reads the real frame through the game’s own camera, so it needs no alignment and reaches runtime-only entities (the player character, spawned props) that have no authored counterpart.
• The game draws a bounding box around the picked entity, and the Live tree expands to reveal the selected row.
• Selecting a row in the Live tree moves the box to that entity.

Menu and UI elements are not pickable; they are not streamable scene entities.

Scene and Live trees

The outliner header has a Scene | Live tab switch:

• Scene shows the authored tree of the open scene file. This is the same hierarchy you edit when the game is not running.
• Live shows the entities the focused game instance currently has, including runtime-only ones. Authored entities the game has not spawned do not appear here.

The two trees are independent. When the game shows a menu, the Live tab shows the menu’s entities while the Scene tab still shows your authored scene, and the Viewport keeps showing that scene with gizmos, fully editable. You can select and edit authored entities in the Viewport or Scene tab at any time without disturbing the running game’s frame.

Stopping and reloading

• Stop ends the game process. The Game panel returns to its idle state and the LIVE badge clears.
• Reload relaunches with the current window-mode setting, which is how you apply a change to the Embedded / Windowed button.