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Algodoo | Phun

It sounds like you're referring to Phun and Algodoo — two interactive 2D physics sandbox simulators.

Here's a short text explaining them:

Phun was a popular, playful physics sandbox where users could draw shapes, create joints, and simulate real-world physics in real time. It was especially known for its fun, intuitive interface and creative community.

Algodoo is the more advanced, continued version of Phun (developed by the same original creator, Emil Ernerfeldt, under the company Algoryx). It adds better graphics, more tools, scripting with Thyme, and support for modern operating systems. Algodoo is widely used in education to teach mechanics, optics, and even simple robotics — all while keeping the "playful" spirit of Phun.

If you'd like, I can also write a short example scene description or give you a few lines of Thyme script for Algodoo. Just let me know. phun algodoo

Hinges (The Axis Tool)

The Hinge is the most important tool in Algodoo.

  1. Select the Axis/Hinge Tool.
  2. Click on an object, or where two objects overlap.
  3. If you click a single object: It pins that object to the background. It can rotate, but won't fall.
  4. If you click where two objects overlap: It joins them together at that point.

1. Getting Started

Part 1: The Origin Story – The Birth of "Phun"

The story begins in 2007 at Umeå University in Sweden. A master's student in Physics, Emil Ernerfeldt, wanted to create a piece of software that was equal parts educational tool and addictive toy. His goal was to allow users to draw shapes, hinges, chains, and motors with a mouse, then watch those objects react to gravity, friction, and restitution in real-time.

He called it Phun (a play on "physics" and "fun").

2. The Physics Menu (The Real Magic)

Closing thought

Phun Algodoo blends learning and play. It demystifies physics by making abstract ideas tangible, encourages experimentation, and rewards curiosity—perfect for anyone who likes to build, break, and discover how the physical world works. It sounds like you're referring to Phun and

If you want, I can:

(formerly known as ) is a free 2D physics sandbox software used by students, educators, and hobbyists to create and explore interactive physical systems. It was originally created by Emil Ernerfeldt as a master's project and is now developed by Algoryx Simulation AB Key Features of Algodoo Intuitive Drawing & Tools

: Users can "draw" physical objects like circles, boxes, and polygons using a simple GUI. Specialized tools allow you to add to build complex machines like Rube Goldberg devices. Real-Time Simulation

: The software uses a powerful physics engine (based on the SPOOK linear constraint solver) to calculate interactions like collisions in real time as you play with your creations. Fluid Dynamics : Unlike many basic simulators, Algodoo includes a Smoothed-Particle Hydrodynamics (SPH) Phun was a popular, playful physics sandbox where

method to simulate water and other liquids, allowing for experiments with buoyancy and hydrostatics. Optics Engine : A built-in engine allows for the simulation of light refraction through lenses of any shape. Data Visualization : You can generate live graphs

of physical quantities such as velocity, momentum, and kinetic energy vs. time. Scripting with Thyme : Advanced users can use the built-in scripting language,

, to program custom behaviors, event triggers, and complex logic for their simulations. Algobox Community

: A massive online repository (Algobox) exists where users have shared over 200,000 "scenes" that others can download and modify. Version History & Availability Version/Product Release Info February 1, 2008 Original name Algodoo 1.4 August 31, 2009 Rebranded release Current Stable (2.2.4) July 10, 2025 Latest update Algodoo for iPad Paid app ($4.99/£4.99) iOS/iPadOS Desktop Version Windows, macOS The software is also highly optimized for interactive whiteboards

and touch-screen devices, making it a popular choice for classroom demonstrations. , in Algodoo?