README

ALIEN: Explore worlds of artificial life



A GPU-accelerated artificial life simulator for studying emergent ecosystems
and the conditions for open-ended evolution



🏆 First prize at the ALIFE 2024 Virtual Creatures Competition
with the video Emerging Ecosystems










!Preview

 🧬 About

ALIEN (Artificial LIfe ENvironment) is an artificial life simulator built on a specialized 2D particle engine for soft bodies and fluids. Every object in a simulated world consists of particles. They can be bonded into elastic solids, flow as fluids or act as cells with specialized functions such as sensors, muscles, weapons and constructors. Each cell is controlled by its own small neural network. Networks of cells form creatures, digital organisms that perceive their environment, move, feed, compete and build offspring according to their genome. Once mutations are switched on, the simulation needs no further intervention. Populations can adapt, lineages diverge and entire ecosystems emerge.

The engine runs entirely on the graphics card and simulates worlds with millions of particles in real time. You can interact with a running world at any moment: draw matter, push creatures around, change the laws of physics or let an AI agent do it for you.

The development is driven by the desire to better understand the conditions for (pre-)biotic evolution, the growing complexity of biological systems and the open question of how evolution can keep producing novelty. At the same time, ALIEN aims to be approachable, with a modern user interface, appealing rendering and a playful spirit.

 ⚡ Highlights

 Physics on the GPU
- Particle-based simulation of soft and rigid bodies, fluids, adhesion, fracture and damage
- Millions of particles in real time, written entirely in CUDA and also available for AMD GPUs
- Rendering and post-processing via Vulkan with CUDA-Vulkan interoperability
- Hardware ray tracing: living tissue, glowing nebulae, and shafts of light and shadow
- Real-time interaction with the running simulation

https://github.com/user-attachments/assets/27f244b2-2792-4854-9042-6c8b179638c0

 Digital organisms
- Creatures are networks of cells, held together by elastic connections that carry energy and signals
- 15 cell types, among them sensors, muscles, attackers, injectors, digestors, memory cells and communicators
- Every cell runs a small neural network. Together, these networks form the nervous system of a creature.
- Genomes are blueprints made of genes. Cells read them and build offspring cell by cell.
- Energy never appears out of nothing. It circulates between cells, free energy particles and an optional external pool.

 Evolution without a fitness function
- Mutations of neural networks, cell properties and the genome structure, with mutation rates that can evolve themselves (meta-mutations)
- Selection arises naturally from limited energy, predation and competition for space
- Layers and radiation sources let the simulation parameters vary across t