Flux

Flux is a powerful data-driven particle API for Paper. Effects can be defined in code via the Java API, or in JSON files, which makes this library incredibly versatile and beginner-friendly!

The library is split into a common module, which contains the effect/particle API, and individual platform modules that implement the library for specific server software

Currently available:

• Paper (platform-paper)

Features

• Shapes - line, circle, sphere, helix, cuboid, cylinder, torus, polygon, star, heart, arc and composites of them
• Effects - layers of shapes with modifiers (scale, twist) and shaders (solid, gradient)
• Particle systems - emitters and particles with lifetime, velocity, acceleration, drag, forces, block collision, etc. (uses display entities)
• Data files - effects as JSON files, plus Snowstorm/bedrock particle support

Requirements

• Java 25+
• Paper 26.2

Installation

Paper

In your plugin's onEnable() method, call FluxPaper#init(JavaPlugin) to initialise the library, and call FluxPaper#destroy() in onDisable().

Do note that calling init will also start Exo if it hasn't already been started, so if you're also using Exo in your project, make sure to initialise it before you call FluxPaper#init!

import org.bukkit.plugin.java.JavaPlugin;
import org.klyx.flux.paper.FluxPaper;

public class MyPlugin extends JavaPlugin {

    public void onEnable() {
        FluxPaper.init(this);
    }

    public void onDisable() {
        FluxPaper.destroy();
    }
}

Gradle (Kotlin DSL)

repositories {
    mavenLocal()
}

dependencies {
    // Common (required)
    implementation("org.klyx.flux:common:1.0.2")

    // Paper
    implementation("org.klyx.flux:paper:1.0.2")
}

Maven

<!-- Common (Required) -->
<dependency>
  <groupId>org.klyx.flux</groupId>
  <artifactId>common</artifactId>
  <version>1.0.2</version>
</dependency>

<!-- Paper -->
<dependency>
  <groupId>org.klyx.flux</groupId>
  <artifactId>paper</artifactId>
  <version>1.0.2</version>
</dependency>

Usage

Everything playable is a marked as a ParticleLike:

• an Effect - shapes made with vanilla particles
• an Emitter (AdvancedParticle) - made with individual display entities.

Examples for both of these types of particles can be found in the demo module and in the examples/ folder.

Playing a file

ParticleLike particleLike = FluxPaper.blueprints().get("fire/burst");
Playback playing = FluxPaper.follow(particleLike, player, 1.0, List.of(player));

playing.pause();
playing.resume();
playing.stop();

Load a folder with BlueprintRegistry#load(Path)

A spinning torus (Java)

Effect ring = Effect.builder(
    Timeline.builder(4).loop(LoopMode.LOOP)
        .track(Tracks.YAW, Track.between(4, 0, 360, Easing.LINEAR)).build())
    .layer(Layer.of(new Torus(1.2, 0.15)).style(SamplingStyle.SURFACE).density(6)
        .shader(new GradientShader(Gradient.of(0xFF3B3B, 0x3BB8FF), GradientShader.Mode.X)))
    .build();

FluxPaper.play(ring, location, List.of(player));

A spinning torus (JSON)

plugins/[]/effects/spin.json:

{
  "duration": 4,
  "loop": "loop",
  "tracks": { "yaw": [ {"time": 0, "value": 0}, {"time": 4, "value": 360} ] },
  "layers": [ {
    "shape": {"type": "torus", "major": 2, "minor": 0.3},
    "style": "surface", "density": 4,
    "shader": {"type": "gradient", "colors": ["#FF0000", "#0000FF"], "mode": "y", "phase": "query.progress"}
  } ]
}

A fountain (Java)

EmitterSpec emitter = new EmitterSpec(
    new EmitterSpec.Rate.Steady(Expression.constant(60)),
    new EmitterSpec.Lifetime.Once(Expression.constant(30)),
    new EmitterShape.Disc(0.2, false),
    new Direction.Cone(new Vec3(0, 1, 0), 15),
    160
);

ParticleSpec spark = ParticleSpec.builder()
    .lifetime(Expression.parse("1.5 + variable.particle_random_1"))
    .speed(Expression.constant(6))
    .acceleration(new Vec3(0, -14, 0))
    .size(Expression.parse("0.1 * (1 - variable.particle_age / variable.particle_lifetime)"))
    .color(Gradient.of(0xFFFFFF, 0xFFD23B, 0xFF3B3B))
    .collision(Collision.bouncy(0.5))
    .build();

Playback fountain = FluxPaper.play(new AdvancedParticle(emitter, spark), location, List.of(player));

A system can also be registered next to the files with FluxPaper.blueprints().register("fountain", system).

Both effects and advanced particles can follow an entity. Following must be started from the main thread!

Bedrock and Snowstorm files

A particle file exported from Snowstorm/bedrock in general plays natively, and anything that Flux doesn't support (textures, flipbooks, events, lighting) is ignored:

FluxPaper.blueprints().load(folder);
FluxPaper.play(FluxPaper.blueprints().get("rain"), location, viewers);

Expressions

Numbers can be written as Molang-style expressions anywhere a blueprint or bedrock file supports one.

Some things to note: In Molang, trigonometry is in degrees and query.progress goes from 0 to 1 over a loop, so use that instead of query.time to make looping effects loop perfectly

Building

./gradlew build 
./gradlew :demo-paper:runServer