How to Configure Projector Warping (Mesh Warp)

How to Configure Projector Warping (Mesh Warp)

Adjust the output image of a projector by deforming a control-point grid. Use mesh warping to correct keystone distortion, align overlapping projectors, or fit content to curved and irregular surfaces. Choose a base warp mode -- Planar (keystone), Cylindrical, or Toroidal -- to match your screen geometry, then fine-tune with the control-point grid.

[USER-ACTION-REQUIRED: Attach a screenshot of the Output Warping window here]

Before you start

• At least one Projector exists in your scene
• The Projector is routed to a GPU Output in the Video Routing matrix
• The physical projector is powered on and displaying the output
• A test image or content is playing so you can see the warp effect on-screen

Steps

1. Open the Output Warping window

There are two ways to open the warp editor:

• Select the Output in the Outputs panel. In the Inspector, scroll to the Mesh Warping section and click the button to open the editor.

• In the Video Routing matrix, click the wave icon in the column header of the output you want to warp.

The Output Warping window opens with a live preview on the left and a settings sidebar on the right.

2. Select the output to warp

Use the Outputs dropdown at the top of the sidebar to pick the output. Only outputs with a routed Projector appear in this list. If you opened the window from a specific output, it is already selected.

3. Enable editing

Check the Edit checkbox. This enables mesh warping for the output and locks editing to your Backstage instance (other connected instances cannot edit the same output simultaneously). Check Show to display the control-point overlay on the physical projector output as well, so you can see adjustments on-screen in real time.

4. Choose a warp mode (base shape)

Use the Mode dropdown to pick the base shape the warp is built on. Match it to your screen geometry:

For Planar, Cylindrical, and Toroidal, drag the larger base handles to set the overall screen shape before refining with the control-point grid. The number of base handles depends on the mode -- 4 for Planar, 6 for Cylindrical, 8 for Toroidal. Use Reset to flatten the base handles back to planar.

5. Set the control-point grid size

Under the Points section, set the Grid values for horizontal (X) and vertical (Y) control points. The minimum is 3 and the maximum is 1000 in each direction. Start with a low count (e.g. 5 x 5) for coarse corrections and increase later if you need finer control.

Changing the grid resolution resets any existing warp adjustments. Export your mesh first if you want to preserve your work.

6. Select and move control points

Click a control point to select it. The selected point turns red. Move it by dragging with the mouse or using the arrow keys. Hold Shift for large increments or Ctrl for fine adjustments.

To select a rectangular region, click and drag a selection box around multiple control points. You can also extend the selection by holding Ctrl while clicking an unselected point -- this expands the selection to the smallest rectangle that includes both the existing selection and the new point.

To navigate between points without the mouse, press Alt + arrow keys to jump to the next control point in any direction.

7. Add or remove custom control points

Click the + button (labelled Add) to enter add mode. A crosshair appears at your cursor. Click anywhere in the image to place a custom control point at that position. Right-click to cancel add mode. Custom control points can be placed freely and are not bound to the grid.

To remove a custom control point, select it and click Remove. Only manually added points can be removed -- grid points cannot.

8. Adjust the physical projector pose (optional)

If the projector itself is slightly misaimed, you can nudge its position and lens from the warp editor instead of warping around the error. Check Projector (next to the Mode dropdown) to enter projector-edit mode, then pick what to adjust and nudge with the arrow keys:

With a mode picked, the arrow keys adjust in the projector's own frame:

• Left / Right -- move sideways · yaw · horizontal lens shift

• Up / Down -- move up / down · pitch · vertical lens shift

• Page Up / Page Down -- move toward / away from the surface · roll · throw ratio

Hold Ctrl for fine steps or Shift for coarse steps.

9. Enable Spring Mode for smooth adjustments

Check Spring Mode to make surrounding control points follow the point you move. The effect decreases with distance, creating a smooth, gradual warp rather than a hard local deformation. This is essential when warping onto curved surfaces.

Use the direction dropdown next to the checkbox to constrain the spring effect:

• Both directions -- spring affects all surrounding points equally

• Horizontal -- only points in the same row follow

• Vertical -- only points in the same column follow

• Horizontal spring -- spring falloff applied only horizontally

• Vertical spring -- spring falloff applied only vertically

10. Enable Smooth Warp (bicubic interpolation)

When Spring Mode is enabled, a Smooth Warp checkbox appears. Enable it to use bicubic (Catmull-Rom with smoothstep falloff) interpolation between control points instead of the default bilinear mode. This produces more organic, natural-looking curves and avoids visible "creasing" between adjacent warp cells. Use Smooth Warp whenever the surface is curved or the warp adjustments are large.

11. Export your mesh

When you are satisfied with the warp, click Export in the File section to save the mesh as a .bsmesh file. This is especially important before re-routing a projector to a different output -- un-routing destroys the generated warp mesh. Import the saved file after re-routing to restore it.

Un-routing a projector from an output permanently discards the warp mesh for that output. Always export to .bsmesh before changing the routing.

Options explained

Keyboard shortcuts and navigation

Common Mistakes

• Warp looks angular and faceted -- You are using bilinear interpolation on a curved surface. Enable Spring Mode and check Smooth Warp for bicubic interpolation.

• Fighting a badly aimed projector with the grid -- Large keystone caused by projector misalignment is better corrected by picking the right Mode (Planar keystone handles) or with Projector-edit mode (Q / W / E) than by dragging the whole control-point grid.

• Warp mesh disappears after re-routing -- The generated warp mesh is tied to the output routing. Export to .bsmesh before un-routing, then import after re-routing.

• Cannot edit -- controls are greyed out -- Another Backstage instance has the edit lock. The other user must uncheck Edit or close their warp editor first.

• Smooth Warp checkbox is disabled -- Smooth Warp requires Spring Mode to be enabled first. Check Spring Mode, then Smooth Warp becomes available.

• Grid resolution change wiped my adjustments -- Changing the control point grid count resets the mesh. Always export before changing grid resolution.

Tips

• Pick the Mode that matches your screen first -- Cylindrical for curved walls, Toroidal for domes -- and shape the base handles before touching the control-point grid. The base shape gets you most of the way there.

• Start with the four corner points to get the overall shape right, then work the edges, then refine the interior. Increase the grid count only after the coarse shape is correct.

• Use Ctrl-click on a border control point to deselect an entire column or row at once. The preview highlight (green = will be added, orange = will be removed) shows what will happen before you click.

• For multi-projector blends, warp one projector at a time. Enable Show Mesh to see the triangle mesh and confirm your warp is not folding or inverting.

• Zoom into the area you are working on with Ctrl + scroll wheel. The zoom is anchored to your cursor position, so point where you need detail. Press R to reset the view when done.

• Save .bsmesh exports at key milestones. If the warp becomes unusable, import a known-good mesh rather than starting over.

Related

Output Warping -- Reference page for the Output Warping window with a full options table.

Blend Multiple Projectors -- How to set up edge blending between projectors.

Apply a Blend Mask to an Output -- How to apply a blend mask to an output for custom blend shapes.

Set up a manual panorama projection -- Walkthrough for setting up a manual panorama projection with mesh warping.