Open-source alternatives to Liquidfun

Bullet3 is a professional physics simulation engine designed for calculating rigid body, soft body, and collision dynamics within 3D environments and robotics applications. It functions as a computational framework for determining complex geometric intersections and contact manifolds between objects in simulated space. The library distinguishes itself through a distributed rendering framework that scales heavy graphical workloads and scene generation tasks across large clusters of machines. This capability enables the production of massive datasets by distributing complex scene generation acr

jetson-inference is a set of libraries and tools for executing optimized deep learning models on embedded GPU hardware. Its primary purpose is to enable real-time computer vision and AI inference at the edge with low latency and high throughput. The project distinguishes itself through high-performance streaming analytics and the ability to execute concurrent AI pipelines on auto-grade silicon. It provides specialized support for multi-sensor stream processing, utilizing zero-copy data transport to load camera frames directly into GPU memory. The codebase covers a broad surface of capabiliti

planck.js is a 2D rigid body physics engine for JavaScript and HTML5, based on Box2D. It provides a framework for simulating physical interactions and calculating the motion of solid objects within a two-dimensional virtual environment. The engine is designed for cross-platform web gaming, enabling the implementation of rigid body dynamics across different web browsers and devices. The library manages simulation through a constraint-based physics solver and rigid body state management. It utilizes iterative impulse resolution, semi-implicit Euler integration, and dynamic AABB tree partitioni

Box2D is a 2D physics engine and rigid body simulator designed to compute collisions, forces, and joints in a two-dimensional plane. It functions as a collision detection library and a constraint-based physics solver that calculates the movement and interaction of solid objects using mass, friction, and restitution properties. The engine ensures consistency across different hardware architectures through a deterministic trigonometry implementation. It prevents high-speed objects from passing through boundaries using continuous collision detection and time-of-impact interpolation. The system

High-performance C++ multibody dynamics/physics library for simulating articulated biomechanical and mechanical systems like vehicles, robots, and the human skeleton.

A fast and lightweight 2D game physics library.

Openframework wrapper for box2d

PhysX is a physics engine SDK designed for calculating real-time rigid body dynamics, fluid simulations, and environmental interactions in virtual applications. It includes a GPU-accelerated physics solver for computing complex particle fluids and combustion models, a voxel fluid simulator for real-time gas, fire, and smoke, and a destruction simulation framework for modeling the fracture of meshes. The SDK features a specialized machine learning physics tensor interface that enables the exchange of simulation data with machine learning frameworks using a common tensor format. It also impleme

Matter-js is a 2D rigid body physics engine written in JavaScript for simulating realistic physical interactions, collisions, and dynamics in web browsers. It functions as a web physics simulation library that calculates motion, gravity, and constraints for objects rendered on a web canvas. The library includes a built-in canvas physics visualizer to draw physical bodies, joints, and constraints for debugging and gameplay. It distinguishes itself through a plugin system that supports recursive dependency resolution and internal method patching to inject custom logic into the engine's executio

MathUtilities is a collection of specialized toolkits providing engines for geometry, computer vision, mathematics, physics simulation, and signal processing. It functions as a comprehensive mathematics and physics library focused on linear algebra, numerical optimization, and geometric calculations for technical applications. The project distinguishes itself through a physics simulation toolkit and a 3D geometry engine. These provide capabilities for Verlet integration, iterative inverse kinematics solvers, distance field rendering via volumetric raymarching, and mesh geometry deformation. I

Panda3D is a cross-platform game engine and 3D graphics rendering system developed for Python and C++. It functions as a comprehensive framework for building interactive 3D applications, providing a real-time physics simulator and a specialized 3D asset pipeline tool. The engine distinguishes itself by combining a high-performance C++ core with interoperable Python language bindings. It utilizes a scene graph architecture to organize 3D objects and provides a pipeline-based asset conversion system to optimize models and textures for runtime loading. Its capability surface includes low-level

cocos2d-objc is an Objective-C 2D game engine designed for developing interactive games and applications. It serves as a cross-platform game framework that enables the deployment of a shared codebase across iOS, tvOS, and macOS. The project features a hardware-accelerated 2D renderer utilizing OpenGL and Metal to display sprites, tile maps, and particle effects. It includes a dedicated OpenAL audio engine for managing music and spatialized sound effects, alongside a cross-platform input handler for processing touch, mouse, keyboard, and accelerometer events. The framework provides capabiliti

This project is a parallel simulation engine and molecular dynamics simulator designed to model the physical movements of atoms and molecules. It functions as an interatomic potential framework for calculating forces between particles and a materials analysis tool for computing thermodynamic, structural, and transport properties of solids and fluids. The engine is distinguished by its high-performance computing capabilities, utilizing spatial-domain decomposition and message-passing interface communication to distribute workloads across processors. It supports multi-backend GPU acceleration v

Cyclone Physics is a three-dimensional rigid body physics engine designed for game development. It provides a framework for simulating the motion, rotation, and physical interactions of solid objects by applying fundamental laws of mechanics. The library utilizes discrete time integration to update object positions and velocities across fixed intervals. It manages complex scenes through a bounding volume hierarchy and employs impulse-based collision resolution to maintain momentum during contact. To handle simultaneous interactions, the engine uses an iterative velocity solver that repeatedly

Newton Dynamics is an integrated solution for real time simulation of physics environments.

Chrono is a multi-physics simulation suite that functions as a multibody dynamics simulator, a finite element analysis tool, and a robotics simulation framework. It provides specialized solvers for fluid-solid interaction and distributed physics engines capable of synchronizing multiple agents across a network. The project features a dedicated pipeline for converting CAD assemblies into simulation-ready formats and integrates directly with robot operating systems to validate autonomous control logic and sensors. It differentiates itself through the use of WebAssembly for portable browser-base

Avian is a 2D physics engine and rigid body dynamics simulator designed to calculate physical motion using mass, forces, and velocity. It provides a framework for simulating rigid body dynamics, collision detection, and joint constraints for games and applications. The engine utilizes a modular physics pipeline with a plugin-based architecture, allowing for the customization of simulation fidelity settings and the extension of collision backends. It includes a specialized kinematic character controller for implementing entity movement and sliding behavior against physical geometry. The syste

LittleJS is a lightweight HTML5 2D game engine designed for building web games using Canvas and WebGL without external dependencies. It integrates a WebGL sprite renderer, a 2D physics engine for arcade-style collisions and rigid-body dynamics, and a grid-based A* pathfinding system for entity navigation. The engine is distinguished by its procedural audio synthesizer, which generates music and sound effects at runtime using parameter arrays to minimize file sizes. It also features a comprehensive graphics pipeline that supports custom fragment-shader post-processing and a dynamic 2D lighting

Space Station 14 is a C# multiplayer game and roleplay simulation framework. It is built upon an Entity-Component-System (ECS) game engine that separates logic into systems and data into components to manage complex entity interactions. The project functions as a grid-based physics simulator with a YAML data-driven prototype system for defining game objects. The project features a specialized 2D sprite rendering engine that maps server-side appearance data to client-side shaders. It implements a networking model with client-side prediction and dirty-flagged state synchronization to reduce inp

Flame is a 2D game engine and framework for Flutter. It provides a component-based architecture to organize scene entities and manage their lifecycles through a structured hierarchy of game objects, coordinated by a consistent game loop. The engine includes a graphics library for rendering animated sprites, particle effects, and external textures. It features a 2D physics integration layer that supports rigid body dynamics and collision detection between entities. The framework covers additional capabilities for game engineering, including user input capture for gestures and gamepads, audio

cocos2d-iphone is a framework for 2D game development and the creation of two-dimensional graphical applications. It enables cross-platform development for iOS and macOS using Objective-C and high-performance graphics rendering. The project provides tools for building interactive environments, including the creation of orthogonal, isometric, or hexagonal tile-based maps. It supports the implementation of rigid body dynamics and collision detection through a 2D physics simulation system. The framework covers a broad range of capabilities, including sprite-based rendering, audio playback manag

Mixbox is a specialized simulation engine for modeling fluid color dynamics, pigment-based hue shifts, and latent space color blending. It functions as an RGB color mixing simulator that uses pigment-based simulations and latent space interpolation to produce realistic results. The project incorporates a Kubelka Munk color engine to achieve physically accurate hue shifts and saturated gradients. It also utilizes a latent space color blender to transform colors into latent representations for precise linear interpolation and multi-color mixing. The system covers fluid dynamics for calculating

Coffee-Physics is a lightweight physics engine designed for two-dimensional particle simulation within web environments. It provides a framework for managing the movement and physical interactions of individual objects across a coordinate system, utilizing a collection of mathematical functions to calculate trajectories and collision responses. The library employs Verlet-based integration to maintain stability by tracking coordinate history, avoiding the need for explicit velocity or acceleration variables. It enforces deterministic behavior through fixed-step time stepping, which ensures con

This project is a multi-purpose web platform serving as a canvas 2D game engine, a frontend engineering blog, and a markdown static site generator. It functions as a web graphics showcase and a technical knowledge base for sharing architectural decisions and performance optimizations. The platform implements a high-performance graphics framework using low-level drawing APIs, integrating skeletal animation and web physics for collision detection and realistic motion of two-dimensional objects. It simultaneously operates as a system for converting markdown source files into pre-rendered HTML pa

FlappySwift is a side-scrolling arcade game implementation built for Apple platforms. Developed using the Swift programming language, this 2D game project features a physics-based environment where a player controls a character to avoid obstacles. The project utilizes the SpriteKit framework to handle rigid body dynamics, gravitational forces, and sprite-based rendering. Game flow is managed through a state machine that controls transitions between the start menu, active gameplay, and game over screens. The implementation covers 2D physics simulation, including bounding-box collision detecti

Flame is a 2D game engine for Flutter and Dart. It provides a component-based game framework for managing entities and their lifecycles through a hierarchical architecture, alongside a dedicated system for game asset management and input handling. The engine distinguishes itself through a specialized integration layer for external physics engines to handle rigid body dynamics and collision detection. It also features a high-performance task model that uses isolates to offload heavy computations and prevent main thread blocking. The framework covers a broad range of capabilities including vis