BeamerMap Manual

Project images and videos onto a house facade, a cube or a curved wall — shaped to fit the object exactly.

Version 0.2.2 · Made by Daniel Vollers

What it does

A projector normally throws a flat rectangle. Real objects are not flat rectangles: a facade has windows and a roof line, a cube shows three faces at an angle, a column is round. Projection mapping bends the picture so it lands exactly on the object.

In BeamerMap you draw surfaces on top of the projector image and drag their corners onto the real object. Every surface shows its own image, video, color or test pattern, warped to fit.

flat projector image
Surfaces are fitted onto the facade; masks keep the windows and door dark.

What you need

A Windows PCRun BeamerMap.exe, no installation needed.
A projectorConnected as a second screen. Brighter is better outdoors.
Your mediaImages (PNG, JPG…) and videos (MP4, MOV, MKV…).
OptionalA presentation clicker to switch scenes wirelessly.
Set Windows to “Extend”. Press Win + P and choose Extend, so the projector is its own screen. With Duplicate your desktop would be mapped too.

Quick start

  1. Place the projector so it covers the whole object, and keep it fixed — every bump means realigning. Turn off the projector's own keystone correction.
  2. Start BeamerMap. Choose the projector in Projector and press Show output (F5).
  3. Click + Surface. A test pattern appears on the object.
  4. Drag the four corners onto the corners of the object. Look at the real object, not at the screen.
  5. Choose Content → Image or Video, or simply drop a file onto the window.
  6. Save with Ctrl + S. Press F2 to hide the corners for the show.

The window

New Open Save │ + Surface + Cube + Mask │ Projector ▾ Show output │ Pause Restart ☑ Surface 2☑ Surface 1☑ Mask 1 PropertiesContent · Crop Mesh warpSoft edges ▶ Scene 1Scene 2 Crossfade 2 sAuto advance 12345
PartWhat it is for
1 · ToolbarFiles, adding surfaces, choosing the projector, playback and volume.
2 · SurfacesAll surfaces, top layer first. The checkbox shows or hides a surface. Use Up/Down to change the stacking order.
3 · PropertiesSettings of the selected surface: content, crop, mirror, mesh warp and soft edges.
4 · PreviewExactly what the projector shows, with handles for editing.
5 · ScenesThe cues of your show, with crossfade and auto advance.

Surfaces, cubes and masks

+ SurfaceFour corners, perspective-correct. One wall, a door, a sign, a screen.
+ CubeThree faces (top, left, right) with shared corners that move together.
+ MaskA black shape on top of everything: windows, doors, a tree in the way.
The red corner belongs to all three faces. Drag it and all three follow. Hold Alt to drag one face's corner on its own. This works for any corners that touch.

Mask shapes

A mask starts as a square. Double-click an edge to add a point there, right-click a point to remove it. This way you can trace an arched window or a roof line.

Layers

Surfaces lower in the list are drawn first; higher ones cover them. Masks always cover whatever is beneath them.

Aligning precisely

Use the Test pattern while aligning: the grid, diagonals and circle reveal at once whether a surface is skewed. The corner labels TL TR BR BL show which way up the content is.

To do thisUse
Drag a cornerLeft mouse button on a handle
Move a whole surfaceDrag inside the surface
Very fine draggingHold Shift while dragging (10× slower)
Nudge by one projector pixel← → ↑ ↓, with Shift 10 pixels
Select the next / previous pointTab / Shift + Tab
Back to a neat rectangleMake rectangle
Edit on the projector. With Corners on projector (F2) on, the handles also appear on the object itself and you can drag them on the output screen. Stand next to the object, look at the projection, and nudge with the arrow keys.

Content and crop

Each surface shows a test pattern, an image, a video (looping) or a plain color. Set Opacity to blend, and Mirror to flip horizontally or vertically. Drop several files on the window and each extra file gets its own surface.

One video across a whole facade

Give every part of the facade the same video and a different Crop (x, y, width, height from 0 to 1). Surfaces that play the same file stay perfectly in sync, so the facade shows one continuous film.

0 – 0.330.33 – 0.670.67 – 1 video.mp4
Crop x 0, 0.33, 0.67 with width 0.33 on three facade parts.

Mesh warp for curved surfaces

Four corners are perfect for flat surfaces. For a column, an arch, a dome or a slightly uneven wall, switch on a mesh: a grid of points you can place one by one.

  1. Select the surface and fit its four corners first.
  2. Set the Grid (columns × rows), for example 5 × 3 for a column.
  3. Click Mesh on. The grid follows the perspective of your surface.
  4. Drag the points onto the object. With Smooth (curved) the picture bends in round curves between the points; without it, in straight pieces.
Raise the middle points of the top and bottom rows to wrap the picture around a column.

You can change the number of points afterwards: the shape you made is kept and resampled. Mesh off returns to the four outer corners. Shared corners with other surfaces keep working with a mesh.

Soft edges

A hard border can look harsh on brickwork or plaster. Soft edges fade the picture to black towards the left, top, right and bottom side, each as a percentage of the surface. The fade follows the warp and the mesh.

left 30% · right 30%

Falloff shapes the fade: below 1 the picture stays bright longer, above 1 it darkens sooner.

Two projectors? Run BeamerMap on each projector PC and give the overlapping sides a soft edge of the same width. The two fades add up across the seam; adjust Falloff until the overlap is as bright as the rest.

Scenes and shows

A scene remembers what every surface shows: media, color, opacity, crop, mirroring and visibility. Where the surfaces are — corners, mesh and soft edges — is shared by all scenes, because that belongs to the building and not to the show.

  1. Set up the content for the first look and click + Scene.
  2. Click + Scene again: the new scene starts as a copy. Change the content of the surfaces.
  3. Repeat for every moment of the show. Rename a scene by double-clicking it.
  4. Set Crossfade for a smooth transition into a scene, and Auto advance after to let the show run by itself.
  5. Press ▶ Play show (F6) to start the show. ⏸ Pause show freezes the countdown; playing again continues with the time that was left. Next to the button you see how long until the next scene.
The show starts paused. While you are still editing, scenes never jump away by themselves. Auto advance only runs after you press Play. Switching scenes by hand (click, PgDn, PgUp) always works, paused or not. The toolbar's Pause (Space) is separate: it pauses the videos.
Scene 1 · Intro Scene 2 · Colors Scene 3 · Finale crossfadecrossfade PgDn → next scene · PgUp → previous · Ctrl+1..9 → jump

During the show, PgDn and PgUp step through the scenes. Most presentation clickers send exactly these keys, so you can run the show from the audience. After the last scene the show wraps to the first.

Keyboard reference

KeyAction
F5Show / hide the output on the projector
F2Show / hide the corners on the projector
Esc (on the projector)Close the output
Space · HomePause / play videos · restart videos
PgDn · PgUpNext · previous scene
F6Play / pause the show (auto advance)
Ctrl + 1…9Jump to scene 1–9
Ctrl + Q · Ctrl + MAdd surface · add mask
Ctrl + D · DeleteDuplicate · delete surface
Arrows (Shift = ×10)Nudge the selected point or surface
Tab · Shift + TabNext · previous point
Ctrl + Z · Ctrl + YUndo · redo
Ctrl + N · O · SNew · open · save project
F1Open this manual

Tips for a great result

Darkness winsProjection only shows well in the dark. Outdoors, start after sunset.
Fix the projectorEvery millimetre of movement shifts the mapping on the wall. Use a sturdy stand and tape.
Native resolutionSet the projector screen in Windows to its native resolution, then align.
No keystoneSwitch off the projector's keystone and lens shift tricks; BeamerMap does the warping.
Black is “off”Black pixels throw almost no light. Design content on black for the cleanest edges.
H.264 MP4Plays smoothest. Very large videos (4K+) need a strong PC.

Media files are stored by path in the project. Keep the project and the media together in one folder, and copy that whole folder when you move to another PC.

Troubleshooting

ProblemSolution
The projector is not in the listCheck the cable and press Win + P → Extend. The list updates automatically.
The output appears on the wrong screenPick the other screen under Projector; the output moves along.
“These media files were not found”The files were moved or renamed. Put them back, or choose them again per surface.
A video stays blackThe format may be unsupported. Convert it to MP4 (H.264).
The preview is empty or flickersOld graphics drivers: update them, or start with BEAMERMAP_RASTER=1.
The mouse pointer is visible on the projectorTurn off Corners on projector (F2); the pointer is then hidden.