"Mobile browsers are basically still a huge mess, except for Safari on iOS, except when PhoneGap'd. So still pretty messy."

Tutorial for using Haxe to make an Android game

Using linked lists in Flash is sometimes faster than using arrays/vectors, probably because the linked lists are expanded to be statically typed, whereas arrays/vectors have some generics going on at runtime (not sure)

Deferred rendering uses a g-buffer to store normals in a texture. The straightforward approach of storing x,y,z in r,g,b isn't great; this page lists alternatives, including performance and accuracy.

"So I thought it would be a good idea to make a big list of AI interview questions ... some that I've asked, some that I've been asked, and others that I think are worth asking." - from Paul Tozour

Explanation and in-browser demo of metaball algorithms

"Have you ever had a memory instantiation problem that was impossible to track down? Here is a post that might help you with that kind of thing!

Beware! This post is very long… but VERY instructive! If you want to learn some internal mechanism of Flash, I strongly suggest you read it from top to bottom without skipping parts!:)"

Lighting for games like Minecraft

2d bin packing algorithms, useful in games (e.g. texture atlas creation)

"This article is a design article about implementing deferred rendering. The motive behind it is that while there have been many articles and presentations about the concepts behind deferred rendering (for example, the article about deferred rendering in Killzone 2), there is very little information about how to approach it from a design standpoint. This article aims to do just that. The article is accompanied by code that implements a deferred rendering framework, and is somewhat a development journal of that framework. "

Networking in Quake 3: delta compression, unreliable packet delivery, acknowledgement messages

How many users get hardware accelerated WebGL? Among Firefox users (~25%), it varies from 21% to 58% on Windows, 40% on Linux, and 80% on Mac. It's probably similar on Chrome, so my guess is that 20-30% of users overall (IE doesn't support WebGL) can use WebGL. I don't think WebGL has a software fallback (unlike Flash 11) but I'm not sure.

Flash 11 notes: (1) 50% of Flash 11 users have hardware acceleration turned on, (2) they're being very careful about turning on hardware acceleration on drivers they haven't tested or are flaky, (3) future releases will have hardware acceleration enabled on more hardware, (4) Flash 11.2 will auto update (finally)

List of game postmortems (game developers look back on their development process to see what went well and what didn't)

Revenue and sales numbers for hit games and average games on iOS

Game control handling -- movement, jumps, camera, etc. -- is often a place where the simplest approach isn't the best. This post describes some things that Wind-up Knight does.

Nicely rendered game maps for GTA:SA

Examples of how visualizations of internal game data can help the game development process.

A train set designer for for OpenTTD describes what goes into the design: players having interesting choices to make, length of wagons, cargo capacity, speed vs capacity, rail types, different time periods.

Developer blog of someone who's working on a Minecraft-like game, and is describing every step.

Spelunky's procedural generation of maps uses room patterns that are mostly set with some variables, and obstacles that are dynamically placed based on pattern matching.

"Slippery slope is usually a bad property in a game. If a game has a powerful slippery slope effect, that means that when one player gets a small early lead, he is more likely to get an even bigger lead, which in turn makes him more likely still to get yet an even bigger lead, and so on. In a game like this, the real victor of the game is decided early on, and the rest of the game is futile to play out (or to watch)."

"In videogames there are often times where you want an impact to feel harder than it really is. There are a lot of variables that can be used to achieve this. Obviously sound is really important as well as blood, screen shakes, controller shake, etc. One VERY important ingredient to this is the use of hit pause. "

Article explaining how to procedurally generate cavern structures like 2d maps in King Arthur's Gold / Terraria, or 3d maps in Infiniminer / Minecraft.

One game's approach to random numbers. Try to make the "random" numbers match the player's perceptions, not what's mathematically pure.

Tutorial for making an Angry Birds like game in Flash.

"Ren'Py is a visual novel engine that helps you use words, images, and sounds to tell stories with the computer. These can be both visual novels and life simulation games. The easy to learn script language allows you to efficiently write large visual novels, while its Python scripting is enough for complex simulation games."

Journey a player takes from learning about a game to being really engaged with it. MMO focused.

Another technique for making transition tile art for tile based games.

Blog post about death penalty in games, plus lots of discussion in the comments

"In other words, players will trade time for safety, but they risk undervaluing their own time to the point that they are undermining their own enjoyment of the game. A classic example is the skill system from Morrowind, which rewards players for repeating any activity. Running into a wall for hours increases the Athletics skill while jumping over and over again increases the Acrobatics skill. Many players couldn’t stop themselves from spending hours doing mindless activities for these cheap rewards."

Design docs, including file/memory formats, for Ultima 6.

Attrition in RPGs: in some games, your health and spells don't recover between battles, so you have to carefully plan.

"I’m reminded of just how much presentation gets in the way of features.  You lower the bar on presentation detail (and the requisite work needed to create it), and you can go for a larger scope. Like having ghosts of former characters appear to haunt your new character. Adding a new monster that only needs text and an existing ascii symbol is relatively simple. Once you start requiring new models, animations, sounds, AI, etc. – it becomes an issue.  All companies – big or little, mainstream or indie – have a limited amount of resources to throw into a game.  Devoting it to one area means less left over to put in another. And if you raise the bar of quality in one spot, it’ll make everything look more shabby by comparison unless you bring everything else to a consistent quality."

Does crafting in an MMO have to be fun by itself, or can it rely on the context, inputs, and outputs to make it interesting?

Simple shadows in 2d top-down games, along with some interactive demos.

"A common way to represent a polygon mesh is a shared list of vertices and a list of faces storing pointers for its vertices. This representation is both convenient and efficient for many purposes, however in some domains it proves ineffective." … the half-edge structure is very useful for polygon meshes.

Game design article: what kinds of actions do players perform, and how often do those actions occur?

"Game designers also need to communicate something effectively – a set of rules and mechanics that the player must learn and master. This education process is one of the biggest challenges game developers face, and many games with fun systems have failed simply because few players get past the learning curve. Many tools exist for solving this problem – well-paced tutorials, helpful tooltips, accessible UI – but perhaps the simplest approach is to activate one of the player’s pre-existing schemas that is well matched with the game’s underlying mechanics."

"Crazy Eddie's GUI System is a free library providing windowing and widgets for graphics APIs / engines where such functionality is not natively available, or severely lacking. The library is object orientated, written in C++, and targeted at games developers who should be spending their time creating great games, not building GUI sub-systems!"

Series of explanations about lag compensation in networked shooter/action games: backward reconciliation, prediction, extrapolation, etc.

Craig Stern made some sound effects and music for the TIGsource Assemblee competition. Some of these were used in Realm of the Mad God

Many game developers are dismissing story and focusing on gameplay, but story can add to the enjoyment of the game

"How do we make story a meaningful part of MMORPGs? A dynamic world is a necessity, of course, but with a dynamic world it’s easy for the state of the world to become difficult to figure out for even veteran players. There needs to be a way for players to easily grok the state of the game world in order to allow players to make intelligent decisions that will have meaningful effects on the world. We can do this by creating a robust system for aggregating in-game history. Let’s see what we need to make this happen."

Aliens and non-human species tend to be depicted as more homogenous than humans, often to the point of being illogical.

Designing building layouts for games

In combat stories where protagonists don't die, each hero kills lots of enemies, so the enemies must be weak and numerous. These weak enemies are often portrayed as non-human (zombies for example).

Interview about Dwarf Fortress map generation and simulation

Beginner introduction to 2d vector algebra for games.

Oblivion has both procedural and hand generated content. This page lists various parts of the game and which approach they used.

Jonathan Blow's articles in Game Developer magazine

11 part tutorial on making pixel art, with sections on terrain, small characters, large characters, and animation

"Fast, powerful and professional new tweening engine developed by Yoshihiro Shindo" MIT license.

Process of balancing an MMO. via nelson

Although players always want demos, it's not clear if it's better for game developers to provide them. Sometimes players won't invest enough in a demo to learn the fun depth of the game, whereas if they buy the game, they're motivated to spend a bit of time learning how to play. This blog post looks at many game demos.

"A good game prototype is something fast/cheap that allows you to answer a specific question about your game. The key points there are fast/cheap and specific question. It’s not a level of a game, it’s not a “vertical slice”, and it’s certainly not an engine for the game."

"Well in the simplest sense, it is a different representation of points in space, but rather than showing the points themselves they are visualized by the pixels around them. So, as you will see in the pictures below the further the pixel is away from the point the brighter it will be. This of course can be inverted. With this gradients can be formed from the point going outwards in all directions . "

Tonfall is an Actionscript framework to get you started in audio dsp programming within the Flashplayer(10+). Tonfall introduces only a vague design of an audio engine and is rather focussed on readability and simplicity than performance optimizations. Tonfall was initially written for the 'Audio Code Clash' workshop at 'Flash on the beach' conference 2010 in Brighton.

[Forum discussion] Pixel art techniques and how-to (scroll down)

How to choose random points on a 2d surface so that points aren't too close to each other (which happens if you pick completely randomly)

Indie games: how much they've sold, how much money they've made, how long they took to make, etc.

Short tutorial for shadows for 2d top-down games

Bullet contrast, patterns, explosions, hit box, etc.

Speeds, sizes, scales, etc. in Canabalt.

The text of the book “The Algorithmic Beauty of Plants”

Stages of a typical "boss" encounter in a game

47 game mechanics

A list of things that might make games fun, and examples of games that use those things.

“We consider the case in which each agent navigates independently without explicit communication with other agents. Our formulation is an extension of the Velocity Obstacle concept, which was introduced for navigation among (passively) moving obstacles. Our approach takes into account the reactive behavior of the other agents by implicitly assuming that the other agents make a similar collision-avoidance reasoning.”

Unskilled players find a game unfair if it rewards skill; skilled players find a game unfair if it doesn't reward skill.

Fractal Brownian Motion, as Brownian Bridges, can trace shapes that look like islands. May be useful for generating game maps.

The camera logic in Super Mario World is much more involved than I would've expected. via nelson

Lots of random name generators (medieval, scifi, places, people, etc.)

Nice collection of game maps and generators to build simple game maps.

Collection of links about graphic/rendering for games

“ In this paper, we present a tile-based texture mapping algorithm by which we only have to physically store a small set of texture tiles instead of a large texture. Our algorithm generates an arbitrarily large and non-periodic virtual texture map from the small set of stored texture tiles.”