The Projector

Projector

Everything is a screen.

Projector turns any flat block surface in Minecraft into a working display. Walls, floors, ceilings, stair sides, slab tops, anvil surfaces, workstation faces - if a block has a face, you can put text, images, video, music, a live clock, a scoreboard or a playable board game on it. No special screen block required: your existing build becomes the screen.

Runs on both NeoForge 1.21.1 and Fabric 1.21.1 (Java 21). Same mod, same features, same data format — pick the jar that matches your loader. Client and server both need the mod.

Why it feels different

• Any surface, not just full blocks. Partial shapes such as stairs, slabs and anvils work; widgets are laid out on a canvas measured in 1/16-block units, so a widget edge can sit inside a single block.
• Everything is adjustable, nothing is snap-to-grid. Size, position, rotation, opacity and layer are continuous sliders with a live preview that uses the same renderer as the world.
• A shared screen, not a private HUD. Plane contents live on the server. Everyone standing in front of the same wall sees the same text, the same video frame, the same song at the same position and the same chess position.
• Built to survive real servers. Content protection, delete protection, per-plane naming, creator transfer, upload quotas, distance-based syncing and de-duplicated media transfers.

Which file do I need?

Projector ships one build per mod loader. They are the same mod — same features, same widgets, same plane data format — you only need the one that matches the loader you play.

• Both are published from the same source tree; the Fabric build lives on the 1.21.1-Fabric branch of the repository.
• Never install both jars at once — pick one loader and one file.
• Always use the -all jar: it contains the audio decoding libraries the mod needs.
• A world can be opened by either loader in single-player; on a server, all players must use the same loader as the server.

Quick start

1. Install the mod on the client and on the server (use the -all jar, see Install below).
2. Look at a wall from up to 48 blocks away and press U.
3. The plane under your crosshair highlights and is selected. Press Esc to cancel.
4. Press U again to open the plane dialog: rename it, add widgets, toggle content protection, or transfer/delete the plane.
5. Right-click any widget in the world to open its own editor.

Controls

Every keybind can be re-bound in Options > Controls.

Widgets

Animations

Every widget can be driven by a small timeline: an entrance animation, an exit animation and a loop animation, each with its own delay and duration, plus drag-to-arrange clips.

• 13 entrance animations, 13 exit animations, 8 loop animations.
• Runs on the plane, so all players see the same animation at the same moment.
• A full-screen preview mode lets you walk around inside the animation while it plays.

Multiplayer, permissions and safety rails

By default any player may delete any plane that is not delete-protected (that is the expected behaviour for creative and shared-world servers). Every refusal is written to the server log with the reason, so nothing fails silently.

Planes are synced by distance: a player receives a plane when they come within range and it is removed again when they leave, so a large world does not push every plane to everyone.

Install

1. Install the loader for Minecraft 1.21.1:
   • NeoForge 21.1.x → use projector-<version>-all.jar, or
   • Fabric Loader 0.16+ → use projector-fabric-1.21.1-<version>-all.jar and also install Fabric API (fabric-api, 0.116.x for 1.21.1 or newer).
2. Drop that -all jar into mods/ on both the client and the server. The -all file contains the audio decoding libraries the mod needs; the other jar does not.
3. Start the game. No setup is required.
4. Optional, only if you want more (install the build that matches your loader):
   • WaterMedia - required for video playback.
   • WaterMedia Android Bridge - additional requirement on Android launchers (see Known limitations).
   • MCEF - required for the web page widget, desktop operating systems only.

Keep exactly one Projector jar in mods/.

Server configuration

A config file is generated at <world>/serverconfig/projector-common.toml. Defaults are sensible; these are the values most servers end up touching.

Compatibility

• Minecraft 1.21.1, Java 21, on either NeoForge 21.1.x or Fabric Loader 0.16+. The Fabric build additionally needs Fabric API.
• Both loaders are feature-complete. The two jars are built from the same source tree; the Fabric build only replaces the loader-specific glue (events, networking, config file, keybinds, mixin hooks). Configuration file and key names are identical on both: config/projector-common.toml, keys U / Esc / O / I.
• Optional mods must match your loader too. Install the NeoForge build of WaterMedia on NeoForge and the Fabric build on Fabric; the same goes for the WaterMedia Android Bridge. Mixing them will not load.
• Iris and OptiFine-style shaders: supported. Three render switches exist because shader packs treat brightness differently - avoidFullBrightLight, realLightForWidgets and surfaceBias.
• Sodium and other performance mods: no known conflicts.
• Android launchers (FCL, PojavLauncher and similar): supported, including touch controls.
• Dedicated servers: plane data is server-authoritative, so single-player, LAN and dedicated servers all behave the same way.

Known limitations

These are deliberate design decisions or hard platform limits, not bugs:

• No built-in video decoder. Video needs WaterMedia. On Android you also need the WaterMedia Android Bridge, otherwise decoding fails - the mod warns you about this at startup. On Fabric, use the Fabric builds of both (WaterMedia 2.1.x plus its Fabric Android Bridge); the Android Bridge declares a hard dependency on a WaterMedia version range, so a mismatched pair refuses to start rather than decoding badly.
• The web page widget does not work on Android. MCEF requires a desktop Chromium runtime, so the widget reports that it is unavailable instead of pretending to play.
• One song, one position, for everybody. Music and video progress are shared on purpose: a plane is a public screen, not a private player.
• Board games are intentionally simplified. Chess has no en passant and treats a stalemate as a loss; go is 9x9 without komi or handicap; gomoku has no forbidden-move rules. Hidden-information games are not offered, because everyone sees the same screen.
• The progress widget uses a font without CJK glyphs, so keep its caption in English, digits or another Latin script.
• Plane contents are pixel-based, not vector-based. Very large text at very small plane sizes will look chunky, the same as any texture would.

External services

The mod talks to the network only for features you deliberately use, and never sends telemetry:

• NetEase Cloud Music public endpoints - search, song details, lyrics and audio links - when you use the music widget. A cookie can be configured in music.neteaseCookie to raise the range of playable songs.
• Bilibili - when you paste a Bilibili share link into a video widget, the mod resolves the playable stream or downloads the file, honouring the caps in the online config section.
• Nothing else. Images, videos and music files you upload live on your own server.

Version status

• 27.2.4 is the current release on both loaders: 27.2.4 for NeoForge 1.21.1 (projector-27.2.4-all.jar) and 27.2.4 for Fabric 1.21.1 (projector-fabric-1.21.1-27.2.4-all.jar). Both carry the same feature set. The Fabric build additionally contains two fixes that also shipped upstream as 27.2.4-snapshot-202/203: WAV audio playback and the video widget getting stuck on its "cannot play" placeholder. Details are in the changelog.
• Fabric line: source and changelog live on the 1.21.1-Fabric branch of the repository. The main branch is the NeoForge line; the two branches share all gameplay code.
• Build numbers (-snapshot-, -pre-, -rc-, -hotfix-) are testing builds published for feedback; they are not releases.

Credits and third-party notices

This mod started as a personal project and thanks:

• Net Music Mod by TartaricAcid and contributors - the music module is derived from it (MIT). See the links at the bottom.
• WaterMedia - optional video backend. Not bundled and not linked: it is used only when installed, via its publicly documented API.
• WaterMedia Android Bridge - optional, Android video decoding. Detected by mod id only; no code from it is used.
• MCEF - optional web renderer used by the web page widget. Not bundled.
• Bundled helper libraries: jlayer, mp3spi, tritonus-share (LGPL-2.1), jflac (BSD), javasound-aac (LGPL-2.1) and night-config (LGPL-3.0). Full notices ship with the mod.
• Minecraft, NeoForge, Fabric and their logos are trademarks of their respective owners. This project is not affiliated with, endorsed by or sponsored by Mojang or Microsoft.

The mod's own code is licensed under Apache-2.0.

Written with DeepSeek V4.1 Flash and DeepSeek Harness. Inspired by the in-level percentage markers of Dancing Line and Through The Fog.

AI Disclosure

Parts of this mod were developed with AI-assisted autocomplete and partial code generation. Game design, integration, and testing were still done by the author.

Links

• Source code and full documentation: https://github.com/hmjmfabc/ProjectorMC
• Bug reports and feature requests: https://github.com/hmjmfabc/ProjectorMC/issues
• Net Music Mod, the origin of the music module: https://github.com/TartaricAcid/NetMusic