Lempo FX

# Lempo Particle Editor

**Design stunning 2D & 3D particle effects visually — and play them in GDevelop.**

Lempo is a standalone Windows desktop editor with a real-time GPU preview, paired with the **Advanced Particle Emitter** extension for GDevelop. Build an effect, export it as JSON, drop it into your game. No coding needed.

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## How it works

1. **Design** your effect in Lempo Particle Editor and export it as a `.json` file.

2. **Import** `AdvancedParticleEmitter.json` into your GDevelop project as an extension.

3. **Add** the emitter object to your scene and set its *ParticleJSON* resource to your exported file.

4. **Run** your game and see the effect in action.

An effect looks the same in the editor, the browser preview, and your game. They all share one source of truth for particle behavior.

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## Features

### 🎛️ Editor

- **12 particle shapes**: circle, square, triangle, star, diamond, line, custom, sphere, cube, pyramid, torus, billboard

- **Custom 3D models & images**: import `.glb` / `.gltf` / `.obj` for 3D, or images for 2D

- **Per-state colors**: separate birth / mid / death colors

- **Gradual shape morph** between birth and death shapes

- **Blend modes**: Normal, Additive, Subtractive, Multiply, Screen, Lighten, Overlay (set per emitter)

- **Force fields**: turbulence, vortex, attractor, and a bounce/friction collision plane

- **Deterministic seed**: the same seed replays the identical effect everywhere

- **Ready-made templates**: Explosion, Fire, Rain, Snow (2D & 3D variants)

- **100-step undo/redo**

- **Over-life Bézier curves** and a gradient editor

### 🌠 Trails & Ribbons

- Dedicated trail mode for both 2D and 3D

- Inspector with width and gradient curve editors

- `time` or `distance` based emission

- **27 ready-made templates** (combat, magic, movement, nature, stylized) with search, favorites, and your own saved presets

- Trails render in-game in GDevelop too

### ⚡ Performance

- **InstancedMesh batching** for 3D particles (~580 draw calls collapse into ~12)

- **C++ accelerated simulation core** for a fast live preview

- **Adaptive viewport** that stays smooth with large particle counts

### 🔍 Previews

- **In-editor GPU preview** (OpenGL 3.3)

- **Browser fast preview** with live sync, rendered with Three.js (3D) / PixiJS (2D)

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## Requirements

- Windows 10 / 11 (64-bit)

- GPU with OpenGL 3.3 support

- No Python installation needed

- GDevelop 5 project (to use the exported effects)

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## Open source

Lempo is released under the **MIT License**. Source code, docs, and issue tracker:

👉 https://github.com/Boy1developer/Lempo-FX

If it helps your game, a ⭐ on GitHub means a lot!

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## Roadmap

Flipbook animation, UV scroll, soft particles, sub-emitters, a timeline with scrubbing, and a preset gallery.

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Made by **Mostafa Fathy (EG dev)**, an independent developer.

🎬 YouTube: https://www.youtube.com/@EG_dev