Skip to content
Lightbridge

Output & Projection Mapping

Lightbridge can send your visuals to any connected display — a projector, a second monitor, or an LED wall.

Opening the output window

Go to View > Output (or press Cmd+Shift+F) to open the output window. It appears fullscreen on your selected display.

The output window is a dumb renderer — it receives the final composited frame from the main window. All your editing happens in the main window; the output just displays the result.

Choosing a display

If you have multiple displays connected, Lightbridge lets you choose which one receives the output. Select the target display before opening the output window.

If a display disconnects

If an output display is unplugged or goes to sleep mid-show, Lightbridge closes only that display’s output — your other outputs and the preview keep running.

If the renderer itself stops (a rare crash or GPU reset), it restarts on its own and the preview comes back automatically. If it can’t recover, a banner appears across the top of the main window with a Restart renderer button — one click rebuilds the preview and your output windows without restarting the whole app.

Keeping heavy sets smooth (Auto-reduce resolution)

Some sources and effect stacks are too heavy for the GPU to draw at full size, especially on a large or high-resolution output. A dropped frame is more noticeable on a projector than a slightly softer image, so when a set can’t keep up, Lightbridge lowers the render resolution until it can, and raises it again when the load drops.

You always know when this is happening:

  • The Res chip in the Output Mode Bar (next to the quality dropdown) turns orange and shows the current scale, for example Res 70%. Hover it to see which set triggered it and how heavy it was. If you use the Balanced or Quality render quality and only that extra sharpness was given up, it shows Res ↓ instead.
  • The first time it happens in a session, a message pops up with a Change button.

Click the Res chip to change the setting:

  • Auto-reduce resolution: on by default. Turn it off to keep every set at full resolution, even if heavy ones drop frames.
  • Keep this set at full resolution: never lower the current set’s resolution, for example a set with text where softness shows. You can also right-click a set tab and choose Keep at full resolution. It’s saved with the show.
  • Hold: the frame rate to protect. 60 fps (default), 30 fps (keeps more detail, smoothness drops to 30), or Display (your display’s refresh rate, e.g. 120 Hz).

Resolution steps down to 85%, 70% and at most 50%. It drops within about a second when a set gets heavy, and steps back up one level at a time, after about 10 seconds of headroom each, so it doesn’t flicker back and forth. While reduced, the picture is enlarged with a sharp filter rather than a plain blur, so edges stay crisp. If you use the Balanced or Quality render quality, that extra sharpness is given up first, before resolution drops below full size.

Projection mapping

When projecting onto non-flat surfaces (buildings, sculptures, irregular screens), use the mapping editor:

  1. Click the Map button in the Output Mode Bar (next to the Hold / Go / Focus controls at the top of the main window).
  2. Each surface is a mesh with control points — a 1×1 subdivision gives you corner-pin (four corners), while higher subdivisions up to 8×8 give you a finer grid for curved surfaces.
  3. Drag the control points to warp the image onto your surface.
  4. Increase mesh subdivision when you need finer control across the surface.
  5. Enable Bezier smoothing for smooth curves between control points.

Editing the mesh

  • Double-click a grid line to add a subdivision line where you need more detail — a column or a row, depending on which line you click. You don’t have to manage rows and columns globally; add points where the correction is.
  • Right-click a control point for a menu: reset the point, select its whole row or column, delete an interior line, or reset the surface.
  • Marquee-drag an empty area (or Shift/Cmd-click points) to select several control points, then drag them together as one move.
  • Set an exact position: with a single point selected, type its X/Y (as a percent of the display) in the Properties panel.

Fine-tuning

  • Arrow keys nudge the selected control point (hold Shift for larger steps).
  • Shift-drag snaps to a 5% grid (a group keeps its shape; a single point lands on the grid).
  • Tab cycles through control points.
  • Magnify toggles a precision loupe that follows the point you’re dragging.
  • Edge blending softens the edges where multiple projectors overlap.
  • Per-surface brightness and gamma let you match brightness across projectors.

Tips

  • The output window runs at the same frame rate as the main window — what you see in preview is what the audience sees.
  • Output configuration is saved as part of your show file.
  • For LED walls or unusual aspect ratios, the surface input rect controls which portion of the canvas maps to each surface.
  • Per-surface brightness and gamma let you compensate for projector hardware differences across a multi-projector rig.
  • Projection Mapping — the architecture: mesh warping, corner-pin, edge blending, per-surface brightness.
  • Output Visuals — preview vs live, auto/hold mode, the output window as a dumb renderer.
  • Performing Live — hold mode, focus mode, and the preview/live workflow.