Tags / Simulation

 

Caustics Simulation in Unity

- Part 4 in a series about creating a realistic water simulation and rendering

Caustics are ripples of light projected onto surfaces behind the refracting surface when light shines through. Caustics have the effect of concentrating light in very distinctive bands because when the refracting surface deforms it acts like a complex lens dynamically bending and focusing the light. Like the refraction, caustics are relatively straightforward to implement in ray-tracing though very computationally expensive. I could find no implementations of real caustics in Unity. The approaches I found use some kind of animation with static baked caustic textures that are warped in a wave-like fashion.
Published Feb 11, 2021  3 min read   unity · simulation · graphics
 

Refracting Water Surface in Unity

- Part 3 in a series about creating a realistic water simulation and rendering

Refraction is the physical phenomena that distorts views through the boundary between two transparent materials that have differing refractive indices. Common examples are looking into water or through a lens. This is very easy to achieve with ray-tracing because it closely simulates the physical process of light moving around a scene. Today (2021) ray-tracing can only be done offline or with limited complexity scenes on the latest hardware. Most games today use a technique called rasterization which is much faster but has many limitations.
Published Feb 11, 2021  3 min read   unity · simulation · graphics
 

Creating the Physics of Water Movement

- Part 2 in a series about creating a realistic water simulation and rendering

In this section we are going to look at simulating the movement of the water surface. We model the surface as a 2D grid of particles. These particles then form the basis of a mesh by rendering triangles between them. A particle is modelled as a point in space with a mass and velocity vector. Each particle is connected to each of its immediate eight neighbours. That is four to the left, right, in-front, and behind, then the diagonals.
Published Feb 11, 2021  3 min read   unity · simulation · graphics
 

Physical Simulation of Water

- creating a realistic simulation of water with refraction and caustics in Unity

Simulating water has been a nerdy hobby of mine for a long time now. My first attempts were on the game Downstream Danger back in 1985. There were a few pre-defined animations for waterfalls and streams. In 1999 I got into DirectX and 3D games development on Windows. I started a game with the working title of Microcosm, but unfortunately I never got it completed. It had landscapes comprised of fractal mountains with simulated erosion.
Published Feb 11, 2021  3 min read   unity · simulation · graphics
 

Simulating Pub Skittles

- to discover optimal playing strategies

Two years ago I created a 2D simulation of the game of pub skittles in an attempt to find the optimum strategies for playing. The simulation used parameters measured from our home alley. (We play in the Malmesbury skittles league at the Volunteer Inn, Great Sommerford.) Different alleys have different characteristics. For example different sized and shaped pins, different balls and different conditions of alley. I had some success with this simulation.
Published Jan 7, 2017  9 min read   fun · simulation
 

Flocking Boids

Today, after a little over eight years, I present a sequel to NetKernel PingPong. Like it’s predecessor, FlockingBoids aims to find that delicate balance between executive toy and technology demo. Finding cool new technologies was the easy part - we’ve got HTML5 (canvas and websockets), JSON, Box2D, and of course NetKernel, your rock solid high performance plumbing. Finding time for executives to play was a little harder… What it does FlockingBoids is a web app that performs a mathematical simulation of autonomous boids which interact in a two dimensional world according to realistic laws of physics.
Published Jun 13, 2013  4 min read   fun · simulation
 

ROC Hockey

As respite from soap-boxing, this week I have a technology demo that was built to provide a testing ground for some new technology I’ve been working on - state machines. State Machines have long been used for embedded systems as a programming abstraction that provides a tight language for programming systems that have well defined modes. They fit a certain class of problems very well and can help provide robust solutions in scenarios where other approaches rapidly become riddled with corner cases and become difficult to test.
Published May 30, 2013  4 min read   fun · computer science · simulation
 

Sand Ripple Patterns

This, perhaps surprisingly, is a subject that I now know far too much about. As part of a side project to recreate an old rendering of a beach scene I wanted a heightmap of some typical sand ripples - you know the ones you always see on every beach and desert. They look mostly like period waves but have interesting joins and branches kind of like magnetic domains. Anyway, even the power of Google couldn’t find anything at all.
Published Mar 4, 2013  2 min read   fun · simulation · graphics