BridgeFalls

BridgeFalls

BridgeFalls is a Minecraft plugin that adds structural stability rules to placed and nearby blocks. If a block has no valid support, it can be denied on placement or marked unstable and made to fall later.

It is designed for Paper/Folia-style servers and includes configurable support rules, visual instability feedback, and in-game admin commands.

Features

- Persistence for placed/broken blocks (vertical, horizontal, top support, and anchor checks) - Persistence with 3D connectivity (including diagonals) - Persistence: mark, warn, persist, and optionally convert to `FallingBlock` - Persistence with configurable particle colors and warning sounds - Persistence for: - non-supporting vertical blocks - non-supporting horizontal blocks - always-stable blocks - always-stable-but-no-support blocks - floating-on-water support blocks - Persistence (for example Creative/Spectator) - Persistence (`/bf config ...`) with validation and reload - Persistence (`GlobalRegionScheduler` + per-region execution) - Persistence of unstable blocks to `unstable-blocks.yml`

Compatibility

- Declared supported Minecraft versions: 21 - Declared supported Minecraft versions: Paper API `1.21.11-R0.1-SNAPSHOT` - Declared supported Minecraft versions: `1.20 - 1.21.11` - `folia-supported: true` in `plugin.yml`

Installation

1. Build or download the plugin jar. 2. Put the jar in your server `plugins/` folder. 3. Start the server once to generate default files. 4. Edit: - `plugins/BridgeFalls/config.yml` - `plugins/BridgeFalls/messages.yml` 5. Use `/bf reload` or restart the server.

Commands

Main aliases:

- `/bf` - `/bridgeFalls` - `/bfCommand` - `/bridgeFallsCommand`

Permission:

- `bridgefalls.admin` (default: op)

Core:

- `/bf help` - `/bf enable` - `/bf disable` - `/bf reload`

Config commands:

- Radius - `/bf config support-radius <value>` - `/bf config top-support-radius <value>` - `/bf config anchor-support-radius <value>` - Behavior - `/bf config fall-delay-minutes <minutes>` - `/bf config time-to-check <ticks>` - `/bf config debug [true|false]` - `/bf config allow-placing-unstable-blocks [true|false]` - `/bf config falling-block [enable|disable]` - `/bf config falling-block drop-item [true|false]` - `/bf config falling-block hurt-entities [true|false]` - Lists (`list`, `add`, `remove`) - `no-rest-vertical` - `no-rest-horizontal` - `always-stable` - `always-stable-no-support` - `floating-support` - `instability-colors` - `disabled-gamemodes`

How support works (high level)

BridgeFalls evaluates support from several angles:

1. Anchor check - checks the 3x3 area below a block - excludes air and materials listed in `no-rest-blocks-vertical` 2. Anchor check - BFS-style search up to `support-radius` - only traverses blocks allowed as horizontal support providers 3. Anchor check - optional upward check up to `top-support-radius` 4. Anchor check - connectivity test within `anchor-support-radius` - uses 3D neighboring blocks including diagonals

If support is missing:

- placement can be denied, or - block is accepted but marked unstable (depending on config)

Marked unstable blocks are periodically re-evaluated. If still unstable after `fall-delay-minutes`, they can fall as `FallingBlock` entities.

Configuration notes

Important keys in `config.yml`:

- `support-radius` - `top-support-radius` - `anchor-support-radius` - `fall-delay-minutes` (`0` means immediate fall) - `time-to-check` (task interval in ticks) - `allow-placing-unstable-blocks` - `falling-block` - `falling-block-drop-item` - `falling-block-hurt-entities` - `disabled-gamemodes` - `instability-colors` - `instable-color` (default outline when falling mode is disabled)

Messages are customizable in `messages.yml` with placeholders (for example `{block}`, `{radius}`, `{count}`, `{minutes}`).

Folia behavior

BridgeFalls uses a region scheduler. All block/world reads are executed per location on the region scheduler, which is the safe model for Folia region threading.

Build from source

```bash

Unix/macOS

./gradlew clean shadowJar

Windows

./gradlew.bat clean shadowJar ```

Output jar:

- `build/libs/BridgeFalls-<version>.jar`

Local Folia run task (project configured with run-paper):

```bash

Unix/macOS

./gradlew runFolia

Windows

./gradlew.bat runFolia ```

Development quality tools

The project is configured with:

- Checkstyle - PMD - SonarQube plugin

License

See `LICENSE.md`.