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World Generation Breakdown

World Generation Breakdown

A large part of Dance of Death v0.6.136 was the addition of world generation. Although the world is little more than a large island at the moment, the results are rather satisfying, even considering that the current method of generating terrain is purely based on elevation. After experimenting with a number of techniques, I settled on this simple formula: 1) Generate Fractal Perlin Noise, 2) Multiply noise by a radial gradient, and 3) Apply terrain and water line. Here is the breakdown:

Neural Particle Deposition

Neural Particle Deposition

In developing an algorithm to generate nodes that are guaranteed to be within a certain distance of each other, I stumbled over this interesting distribution of particles which were initially placed randomly then moved near their nearest neighbor. I’ve dubbed this particle system “Neural Particle Deposition” on account of the organic, neuron-like shapes it produces. Take a look:

World Generation Teaser

World Generation Teaser

Happy 2013 everyone! Rather than risking going three months without an update, I figured I’d post some teaser screenshots of the world generation progress on my latest project:

WeightedLetter Name Generator

WeightedLetter Name Generator

This name generator takes a seed of similar sounding names (or any words), and generates a new set of names based on the likelihood that one letter follows another in the original set. It picks the first and last letter, generates the letters in between, best-matches the second-to-last letter, and runs post-generation triple-letter and Damerau–Levenshtein checks to ensure uniformity with the seed.

Procedural Space Invaders

Procedural Space Invaders

These simple procedurally-generated Space Invaders-style sprites were directly inspired by Jared Tarbell’s classic Invader Fractal. The concept is straightforward: start with a grid of a set width and height (3×5 works well), and mirror on the x all tiles except for the center one. You can see it in action here and grab the source code from GitHub.

Procedural Radial Flowers

Procedural Radial Flowers

At my wife’s request I bring you a direct spin off of the Procedural Space Invaders, only this time rotated along a center axis to create procedural radial spirals, or “flowers”. You can see it in action here and grab the source code from GitHub.

Zwoptex Export for Starling and Sparrow with Trim Support

Zwoptex Export for Starling and Sparrow with Trim Support

If you, like me, have been using Zwoptex to create your spritesheets for Starling or Sparrow, you might have noticed a distinct lack of trim support. That is, Zwoptex claims to be trimming your files, but the resulting XML does not include any such trim data. Use the following file to fix this pesky problem:

Cocos2d iPhone Repeating Sprite

Cocos2d iPhone Repeating Sprite

Since Cocos2d iPhone’s OpenGL is only capable of repeating textures that have dimensions which are a power of two, I’ve put together a quick-and-dirty algorithm to tile arbitrarily-sized sprites to arbitrary sizes. TiledSprite takes a source sprite with a texture from a file or a subtexture from an atlas, and clips and/or tiles to fit the requested width and height. The source code is available on GitHub as a Gist, just copy-paste it, download it, or clone the repo and grab the .h and .m for use in your project.

Jabberwocky in Spanish

Jabberwocky in Spanish

And now for something completely different: dissatisfied with other Spanish translations of Lewis Carroll’s Jabberwocky, I’ve taken a stab at it myself, adhering to the following guidelines:

  1. Most importantly, the spirit, tone, and setting must be maintained.
  2. The Spanish version should not feel like a translation.
  3. The structure, rhyme, and cadence must be maintained.
  4. The meaning must be preserved as closely as possible.
  5. Nonsense words must be translate into similarly evocative nonsense.

Cardinal Movement Relative to Player Screen Position

Cardinal Movement Relative to Player Screen Position

Here’s something you’re likely to have run across: the player character is in the center of the screen, and you want it to move in the cardinal direction you click, relative to its position—clicking above it moves north, below south, to the right east, and to the left west.

I’ve implemented this control scheme in my current project, settling on the following technique after a less-than-elegant implementation relying heavily on if-elses:

Comet Long Polling with PHP and jQuery

Comet Long Polling with PHP and jQuery

Comet describes a number of techniques with which a web server may push information to a client in a non-transactional format. Long Polling is one of such techniques, in which a browser’s request remains open until the server has information to send.

Long Polling is particularly useful in semi-synchronous applications, such as chat rooms and turn-based games, and is straightforward to implement with PHP and jQuery:

The MDA Framework

The MDA Framework

MDA: A Formal Approach to Game Design and Game Research is a paper borne out of talks and workshops given by its writers, Robin Hunicke, Marc LeBlanc, and Robert Zubek, with the aim to formalize the understanding of games by splitting them into three parts: Mechanics, Dynamics, and Aesthetics.

The Quest for Custom Keymapping and International Keyboard Support

The Quest for Custom Keymapping and International Keyboard Support

Normally, in regaining momentum for a project, I’ll pick it back up and work on small-ticket items just to get into the groove again, then work my way into the larger items. Though this time I have done the opposite, I finally have a handle on one of the larger features for version 0.4: custom keymapping.

Experimenting with Bézier Curves

Experimenting with Bézier Curves

A few days ago, I stumbled upon the Wikipedia Article on Bézier Curves. As a fan of procedurally generated art, when I saw the fifth-order Bézier curve animation within that article, I was inspired to attempt my own Bézier curve drawing algorithm. This is what happened. In this article, on ANidea, I break down a basic Bézier curve algorithm and show how it can be generalized to create Nth order Bézier curves.

Dungeon Generation

Dungeon Generation

Although I have worked on two (albeit short-lived) roguelikes prior to Dance of Death, this is the first to feature a dungeon generation algorithm. While it relies greatly on brute force searches, especially for connectivity, I am quite happy with it, and it definitely gets the job done!