Every surface is two things
This is the whole mental model. Once it clicks, the rest of MapCast is just detail. A surface is one piece of media placed on stage — and it holds two independent layers you control separately.
Where it lands on the wall
The outline you drag to match the real object — the corners, the curved edges, the interior warp. This is the part that should bend, because it follows the wall.
How the media fills it
How the video sits inside that outline — stretched to fill, fitted at its true proportions, zoomed, or nudged. Change this without ever touching the shape on the wall.
Quick start — first projection in five steps
- Connect the projector as a second display (Extended, not Mirrored).
MapCast treats your laptop screen as the control room and the projector as the output.
- Import media. Drag a video or image onto the stage, or use + Image / Video in the left panel.
It appears as a surface you can immediately shape.
- Shape it to the wall. With the Move tool, drag the four corners until the picture lines up with the real object.
Need curves or a tilted-projector fix? That's the Bézier and Perspective controls, below.
- Send it to the projector. Click ⧉ Output to open a clean, borderless window on the projector display, then ⛶ Fullscreen.
The output shows only your mapped picture — no toolbars, no handles.
- Save the show. Use 💾 Save all to write a
.pmprojfile that bundles the videos with the layout, so it reopens anywhere.
The workspace
Three areas plus a top bar. You move left → center → right: pick media, shape it on the stage, fine-tune its properties.
Media library
Everything you can project: imported images and video, live sources (camera, screen), a calibration grid, and ready-made example loops. Organize with folders, star favorites, search.
The stage
Your canvas — a 1:1 map of what the projector shows. Drag surfaces and their handles here. Zoom and pan to work precisely; the tool hint at the bottom always tells you what the current tool does.
Surfaces & properties
The stacked list of surfaces (reorder, hide, duplicate, delete) and — when one is selected — every property of it: fit, color, warp, crop, mask, and more.
The top bar
- + Surface N — add a new blank surface.
- ● Edit / ○ Live Tab — switch between building the show and running it. Live hides all editing handles.
- ⬛ Blackout B — instantly cut the projector to black without stopping anything.
- ❄ Freeze Space — freeze the current video frame on the wall.
- ⛶ Fullscreen F · ⧉ Output — send the picture to the projector (see Output, below).
- 💾 Save all / Export layout / Open — see Saving your work.
The tools
Eight tools on the left toolbar. Each has a one-key shortcut. Most of your time is spent in the first one.
Move / Select V
The default. Click a surface to select it; drag its body to reposition, or drag a corner to fit the picture to the wall. This is where most mapping happens.
Transform T
Wraps the surface in a box with handles — scale it (hold Shift to keep proportions), rotate it with the top knob (Shift snaps to 15°), or drag the middle to move the whole thing at once.
Bézier C
Turns the four edges into curves. Drag the pink points to bend each side — the tool for curved walls, arches, columns and domes. Presets give you a head start.
Mesh E
Warp interior points, not just the corners — for uneven surfaces that bulge or dip. Set how many Columns and Rows of points you get in the properties panel.
Mask M
Crop the projection into any shape. Start from a rectangle or ellipse, or draw a free polygon point by point, then drag the points to trim off light that shouldn't be there.
Eyedropper K
Click the projected picture to grab that exact color as the surface's chroma key — the fastest way to knock out a background so only your subject shows.
Hand H · Space
Drag to pan the stage view without moving anything. The mouse wheel zooms at any time.
Zoom Z
Click to zoom in, Alt+click to zoom out, for precise corner work. + / − / 0 also zoom in, out, and fit-to-window.
Surface properties
Select a surface and the right panel fills with everything you can tune on it. Top to bottom:
Content fit — the media inside the shape
Controls Layer 2 from the big idea: how the video fills the surface, without changing the shape you mapped to the wall. Stretch distorts the media to fill the outline (the classic behavior). Fit keeps the media's true proportions, whole and un-squashed, letterboxing any gap. Fill keeps proportions but covers the whole surface, cropping the overflow. With Fit or Fill you also get Zoom and Position X/Y to frame exactly the part you want.
Opacity & Feather
Opacity fades the surface. Feather softens its edges into darkness — essential for blending one projection into the wall or into a neighboring surface.
Color match
Brightness, Contrast, Saturation, Hue — match the projection to the room and to other surfaces, or push a look. One projector runs hot, another cool; this is how you make them agree.
Chroma key
Remove a background color so only the subject projects. Pick the color with the Eyedropper or “Pick from center,” then dial in Key strength (how aggressively it's removed) and Softness (how clean the edge is).
Perspective (keystone)
Pull the top, bottom, left or right edge inward to correct a projector that isn't square to the wall. Alt+click pushes an edge out instead.
Bézier curved edges
Enable curves and shape each edge by hand, or start from a preset — Arch, Valley, Cylinder, Dome, Wave, Straighten. Curvature sets convex vs. concave; Smoothness sets how finely the curve is subdivided.
Mesh, Crop & Mask
Mesh sets the grid of warp points (Columns × Rows). Source crop selects which part of the media is used. Mask crops the projected shape — draw it, invert it (I), and soften its edge.
Transform & layout
Uniform Scale, rotate, flip, and quick Center (both axes, horizontal, or vertical). Fill stage snaps the surface to the whole canvas; Reset corners returns it to a clean rectangle.
Video playback
Per-surface transport: play / pause, stop, and set a loop — mark Start = now and End = now to loop just a segment of a longer clip.
Scenes & performing live
A scene is a saved snapshot of the whole layout. Build several looks, then switch between them during a show.
- + Scene — save the current layout as a scene. Click a scene to apply it; press 1–9 to jump straight to one.
- ✳ Fade — crossfade smoothly between scenes instead of cutting.
- ▶ Auto — advance scenes on a timer; set the seconds between them. Turn it on for an unattended loop.
- Update / rename / delete — re-save a scene with the current layout, or manage it. Double-click a scene chip to rename.
- Live mode Tab — hides every handle for the real show. From here: F fullscreen · B blackout · Space freeze · 1–9 scenes.
Output to the projector
The desktop app drives a real second screen — something a browser can't do.
- ⧉ Output opens a clean, borderless, fullscreen window on every connected projector display, showing only your mapped picture. Click it again to close them — that's your way back, since the output window has no title bar.
- ⛶ Fullscreen F, ⬛ Blackout B and ❄ Freeze Space all act on the live output.
- Everything stays in sync: what you change in the editor updates on the projector instantly.
Media & formats
For rock-solid playback, prep your loops the way the engine likes them.
Ideal: MP4 with the H.264 codec, no audio track, yuv420p, at the projector's resolution. Keep loops short (10–60 s) and seamless — several short loops beat one long file.
VJ loops from the web often arrive as AV1 or VP9, which this Mac's video engine can't decode. When MapCast hits one, it offers to convert it to H.264 in place — a copy is saved next to the original, nothing is overwritten. iPhone .MOV (HEVC) and ProRes are handled the same way.
Also as sources
- + Camera / + Screen — project a live webcam feed or a screen/window capture.
- + Grid and the example loops (color bars, plasma, neon waves, tunnel, particles, neon grid) — for lining up and testing the projector before your real content is ready.
Keyboard shortcuts
| Key | Action |
|---|---|
| V T C E M K H Z | Tools: Move, Transform, Bézier, Mesh, Mask, Eyedropper, Hand, Zoom |
| Tab | Toggle Edit ↔ Live |
| N | New surface |
| F | Fullscreen on the projector |
| B | Blackout |
| Space | Freeze the video frame |
| 1–9 | Jump to scene 1–9 |
| I | Invert the selected surface's mask |
| + − 0 | Zoom in · out · fit to window |
| ↑ ↓ ← → | Nudge the selected surface (hold Shift for larger steps) |
| Delete / Backspace | Delete the selected surface |
| ⌘/Ctrl + Z · Y | Undo · Redo |
Saving your work
💾 Save all → .pmproj
The whole project with the videos included — a portable backup that reopens on any computer exactly as you left it. Use this for anything you want to keep or move.
Export layout → .json
The mapping only, without the media. Small and shareable — useful when the media lives elsewhere and you just want to move the geometry.
MapCast also autosaves your session as you work, so a reopen brings you right back.