Fun & useful weblinks

Here’s a list of assorted links. Some are useful, some are fun and the rest are, well, there. These are simply links I’ve personally found intresting at some point. Some of them may contain weird material.

• Inselkampf
• OGame

• Real Life
• Ctrl+Alt+Del
• Penny Arcade
• VG Cats
• Press Start To Play
• Wulffmorgenthaler
• Chopping block
• Sexy losers
• Cyanide and Happiness
• Saturday Morning Breakfast Cereal
• The Perry Bible Fellowship
• xkcd
• Bigger Than Cheeses
• Bug Bash
• John and John
• Thingpart
• Overcaffeinated
• Digital Unrest
• Awkward Zombie
• Truck Bearing Kibble
• Virtual Shackles

• Jetro Lauha (tonic)
• Jari Komppa (sol)
• Patrick C. F. Ernzer (pcfe)

• Programming languages
  • C/C++
    • Information about sequence points and why they are important to every C/C++ coder.
    • Many good C++ Optimization Strategies and Techniques.
    • Visual Studio specific pseudo registers help debugging a lot (for instance seeing what the last GetLastError() value is or placing a breakpoint that only one thread will trigger).
    • Some good guidelines into the usage of volatile qualifiers in C/C++ code and how it can subtly be used wrong.
  • D
  • F#
    • Functional language for the .NET runtime which is like ocaml. Some ocaml programs compile directly on F# and the language extensions are for easier .NET interoperation. Has an excellent Visual Studio plugin, which gives you intellisense (autocomplete, syntax coloring etc) and static code & compile time type checking.
    • Don Symes blog (he’s the man behind F#)
    • Flying Frog Consultancy limited has some F# examples (for example a simple DirectX example, a raytracer and a sudoku solver).
    • The hubFS contains F# forums and F# related news + information.
    • The F# Survival Guide is a good book that goes over F# from the beginning to the end.
  • Haskell
    • Pure lazily evaluated functional language.
    • Brian Beckman: Don't fear the Monads is a good video tutorial on monads
  • Erlang
    • Functional language that’s designed for parallel distributed computing. The most elegant way to multicompute I have yet seen.
    • Tutorial on how to build a simple fault-tolerant "bank" server.
    • Study on a distributed virtual world MMO game server (done in Erlang of course)
    • The book Programming Erlang: Software for a Concurrent World (2007) is an excellent book newbie to medium cooked Erlang developers (both PDF and paper back available). The website gives the “Getting Started” and “Concurrent Programming” chapters as free sample extracts.
  • Objective Caml (ocaml)
    • Functional language with static typing and native compilers. Has imperative and object oriented features.
    • Typed relational algebra: schemas, CRUD, source code explains a way, using the camlp4 preprocessor, to solve the abstract database access problem.
  • Python
    • Pygame is a set of python modules to ease games development. Runs on top of SDL, portable and runs on many operating systems.
    • PyOpenGL has OpenGL bindings for python programs.
    • Psyco is a JIT like compiler for python programs. It gives unmodified python programs 2-100x speedup benefits.
  • Common Lisp
    • Common Lisp HyperSpec is the online version of the official Common Lisp specification.
    • Practical Common Lisp book (online).
      • Lispbox is a handy all-in-one package. It contains emacs, swine, lisp etc in one standalone package; just unpack and go. This package is referred to by the Practical Common Lisp book.
    • Successful Lisp book (online).
    • Onlisp book (online).
    • Let Over Lambda book (some chapters online).
  • Factor
    • Factor is a concatenative language in which all operations push and pop values from a data stack (a bit like Forth).
    • Factor main authors, Slava Pestovs, blog. Contains lots of information about Factor.
    • Slava Pestov did a Google TechTalk in 2008 where he talks about Factor in good detail.
  • Other languages
    • BitC is a low level well typed C-like programming language (in the lisp syntax), compiles to C code so it’s portable.
• Graphics
  • Global illumination (both on- and offline solutions)
    • The computer graphics group of Athens has a nice collection of original papers on interactive global illumination (as well as sampling, 3D reconstruction and VR/gfx engines).
  • Interesting article about computer generated sketching.
  • ompf contains information and a forum dedicated for realtime raytracing.
  • An intresting small snippet of javascript, showing a pretty efficient flat triangle fill routine.
  • The UNC GAMMA (Geometric Algorithms for Modeling, Motion and Animation) research group site contains a lot of information about haptics, collision detection, motion planning, animation, GPU based algorithms, rendering acceleration (raytracing among others) and solid modelling. (alternative link)
  • Fast approximations for lighting of dynamic scenes -paper (Siggraph 06) gives a few ways to do estimations for realtime ambient occlusion (course notes).
  • Linear-Speed Vertex Cache Optimisation contains an algorithm to generate separate triangles so that they are cache efficient for most hardware vertex caches.
  • A thesis by Martin Storsjö on Efficient Triangle Reordering for Improved Vertex Cache Utilisation in Realtime Rendering has a nice laydown on some common vertex/triangle reordering algorithms.
  • The Fast Precomputed Ambient Occlusion for Proximity Shadows -paper has a fairly simple but extensive method for real time ambient occlusion for rigid objects.
  • A nice paper from Valve, Improved Alpha-Tested Magnification for Vector Textures and Special Effects gives a simple method of doing better alpha tests for textures with sharper and straighter edges using a distance map (encoded in the alpha channel) instead of an alpha mask. Scales from simple fixed function hardware up.
  • Real-time, All-frequency Shadows in Dynamic Scenes, a paper released at siggraph 2008 (here’s a youtube of the results).
  • Diffusion Curves: A Vector Representation for Smooth-Shaded Images paper describes a new vector primitive. The primitive is a bezier curve which divides space and colors each side with smooth gradients, leading to an efficient image packing and manipulation framework. Link contains the paper, a video, a test executable and examples.
  • An interesting blog post by directtovideo, A thoroughly modern particle system, describes how to achieve a million+ particles in real time using GPU for updating & rendering.
  • Slides from GDC 2011 on talk about mega meshes and their use at Lionhead.
• 3D engines
  • Devmasters 3D engine database
  • Wild magic 3D engine. Contains lots of code snippets for various things, including collisions and physics
• Physics
  • Verlet and position based physics
    • The classic paper describing verlet integration based dynamics in games is the Advanced Character Physics paper by Thomas Jakobsen.
    • A paper called Position Based Dynamics (by Matthias Müller) and Hierarchical Position Based Dynamics (by the same guy) describe some methods to make fast (and relatively simple) robust dynamic systems in real time.
  • Open Dynamics Engine (open source)
  • Bullet Continuous Collision Detection and Physics Library (open source, alternate link)
  • Chipmunk is a simple yet stable 2D rigid body physics engine.
  • Box2D is yet another simple 2D rigid body physics engine.
  • Erin's physics blog. Some good insight into simple game physics.
  • Glenn Fiedler (gaffer) has some good physics tutorial articles, starting with basics, using springs and even covering networked physics.
  • Dynamic simulator blog in blogspot. Some useful info, and the author is releasing his source code in the simpack project (in sourceforge).
  • Nonconvex Rigid Bodies with Stacking, a SIGGRAPH 2003 paper.
  • Fast Lattice Shape Matching for Robust Real-Time Deformation. This paper (and some source code) describes a grid based method for making soft body physics.
• Collision detection
  • XenoCollide is a generic convex shape collision detection algorithm based on Minkowski Portal Refinement. The site has an abstract on the 2D version of the algorithm and on the forums you can find a working 3D collision sample with source code and an open license.
  • The Optimized Spatial Hashing for Collision Detection of Deformable Objects paper talks about a simple way to do broadphase collision detection using spatial hashing (storing grids into a hash grid).
• Computational fluid dynamics (game oriented)
  • The classic paper Real-Time Fluid Dynamics for Games (2003) by Jos Stam gives a simple method for doing a grid based simulation of fluids and gasses.
  • Mick Wests Practical Fluid Mechanics (2007-2008) describes some ways to improve on the grid method described by Jos Stam.
  • The thesis titled Physically-Based Fluid Modeling using Smoothed Particle Hydrodynamics (1995) discusses methods that simulate fluids as a set of particles.
  • The slides from nvidias GDC 2008 talk Particle-based Fluid Simulation.
  • Particle-Based Fluid Simulation for Interactive Applications paper (2003) describes a method based on Smoothed Particle Hydrodynamics. They managed to achieve interactive scenes with up to 5000 particles.
  • Particle-based Viscoelastic Fluid Simulation (2005). Their method achieves around 1000 particles at 10fps (20000 particles at 2 secs/frame).
  • Lagrangian Fluid Dynamics Using Smoothed Particle Hydrodynamics (2006). A good and detailed paper on particle based fluid simulation basics.
• Nintendo DS & DS homebrew
  • devkitPro is an open source development toolset (compilers, linkers etc) for Nintendo DS, GBA, PSP and GameCube.
  • The PAlib is an optional tools library for the DS, making basic application development easier (PAlib wiki).
  • Great tutorial into homebrew Nintendo DS programming.
  • Comprehensive and low-level but good specification about GBA/NDS.
• Algorithms and data structures
  • An article about Recursive Dimensional Clustering, an algorithm that finds possibly colliding object groups in logarithmic time.
  • Buckytrees are simple spatial structures with O(N*log N) search times. They are good in that they don’t require any spatial indices (ie. the structure is implicit). Useful in boundary queries and raytracing (for example).
  • Nice wiki for ideas and concepts about procedural content generation.
• Low level stuff
  • Bit Twiddling Hacks. Small code snippets to twiddle bits. Intresting stuff like getting the abs of an integer without branches, checking if an integer is in a power of 2 etc. (local copy, taken on 16.10.2006)
  • Lots of color space conversion formulaes. Lots of them (XYZ, RGB, CMY, CMYK, Hunter-lab to say a few).
  • Resources for software optimization for Intel and AMD processors. Includes advice for C++ and assembly (+ some chat about timings and other low level stuff).
  • What every programmer should know about memory (alternative) (written by Ulrich Drepper).
  • The Gallery of Processor Cache Effects explains in easy to understand terms and examples how the processor cache works and how you can predict its behavior.
  • The Little Book of Semaphores is a free book (PDF and PS) that introduces the principles of synchronization for concurrent programming.
  • What Every Computer Scientist Should Know About Floating-Point Arithmetic is a must read paper for everyone coding with floating points.
• Memory management stuff
  • TSLF (Two-Level Segregate Fit) is a small (code and overhead wise) memory allocator, useful for embedded environments. There is also a public domain implementation found here.
  • DLmalloc (Douglas Lea’s malloc) is considered to be one of the best memory allocators for general use. The site has a description on the algorithm as well as public domain source code.
  • google-perftools contains a really fast, multi-threaded malloc() implementation and some cool performance analysis tools. Released under the BSD license. Contains C++ STL hooks, TCMalloc, heap-checker, heap-profiler and cpu-profiler. Works at least in Windows and Linux.
• Mathematics
  • Essential maths for game programmers. Good references, tutorials and articles.
  • An Intuitive Explanation of Fourier Theory.
  • The Strouhal Number in Cruising Flight explains how the ratios of flying (or swimming) stroke frequency and amplitude correlate to forward speed.
• Parsing (text, binaries etc) and compilers
  • The GOLD Parsing System is a free LALR parser generator for creating own programming/scripting languages. The generator generates parsing files which can then be read by the parser engine (many implemented in many different programming languages). Also contains nifty GUI tools.
  • Link Grammar is a free syntactic English language parser (written in C).
  • ISO CD image for the Small-C Compiler book (contains the book text on the CD)
  • The book The Implementation of Functional Programming Languages is now out-of-print but luckily also freely available book by Simon Peyton Jones (published by Prentice Hall, 1987).
  • Implementing functional languages: a tutorial is an out-of-print book on how to implement a functional language compiler (a few different ways).
• Interesting talks, papers and books
  • Tim Sweeney (of Epic & Unreal fame) on the next mainstream programming language
  • The book titled “Version Control with Subversion” has an online version of the book that gives the basic lay down of working with subversion.
  • The book Structure and Interpretation of Computer Programs (online) talks about generic structures of computer programs. It uses lisp as the base example language.
  • Flow-based programming (FBP) is a programming paradigm where the program is described as network of processes which exchange data through predefined connections. There is a good book on FBP here (1st edition is online, 2nd edition is for sale).
  • The Architecture of Open Source Applications contains tons of case studies and analysis on how many different open source projects are architected.
• Programming competitions
  • Mailing list for coding competitions
  • Ludum Dare hosts 48h game coding competitions every now and then (LD48). I’ve participated a few times and it’s great fun for a weekend.
  • 72 hour game development competition.
• 4k intros and other code size optimization stuff
  • The in4k wiki contains loads of information about 4k intros and small coding tips and tricks.
  • aulds blog contains tons of interesting things on size optimization, graphics and other subjects.
  • Iñigo quilez has a page which has a cool framework (bunch of small intros with sources) for 1k/4k intros.
• Generic programming sites
  • DevMaster.net contains lots of articles, pictures of the day, 3D engine databases and whatnot.
  • GameDev.net is a portal similar to DevMaster.net.

• Texture synthesizer for GIMP. Creates “more” of any given texture. Useful for making tileable textures and removing areas from existing images.
• Blender is a free open source (GPL) 3D modeller. The user interface is a bit different from some of the commercial modellers (3DS MAX and Maya) but I hear once you get used to it, it’s really good (and hey, free).
• GIMP (or GNU Image Manipulation Program) is a free (GPL) alternative to Adobe Photoshop and the like. The UI takes some getting used to, but it gets the job done.
• Exact Audio Copy is a free (cardware) high quality CD audio ripper.
• Useful Unicode conversion website that allows easy transformation between ASCII, UTF-8, UTF-16 and various url/hex/decimal encodings.

• You're in control of this toilet experiment. Some MIT students bolt sensors to a mens urinary and create a game with it.
• The dragon illusion is a simple dragon folded from a sheet of paper but when you look at it, it seems to always look at you. A pure optical illusion but quite cool nonetheless.
• Multitouch stuff
  • reacTable is a project to create a table that creates music. You can place different objects (sound generators etc) on top of it and a camera underneath detects the objects location and orientation. They include their scientific papers and open sourced software on the site as well.
  • Do it yourself multitouch table.
  • Another instruction for a multitouch table. This one doesn’t use FTIR (it has the IR light behind the screen) so it’s a bit simpler to build.
• Origami
  • Robert J. Lang has “solved” the domain of origami using mathematícs. This allows for far greater complexity in origami art and has other fields (anything where you need to pack a planar object compactly, like space telescopes and airbags). The main website is this and he holds a talks about it in TED.