transitive-bullshit / dissolve-generator

Cool 2D dissolve effect generator

Dissolve

Cool 2D dissolve effect generator (demo)

This module exposes a generator for generating pseudorandom points over a 2D integer grid.

The generated points appear random, but they are actually quite deterministic and, in particular, space-filling in that the samples are guaranteed to visit every point in the domain.

This effect was used in a lot of retro video games to transition the screen between foreground and background images.

Usage

Installation:

npm install dissolve-generator

Example usage:

const dissolve = require('dissolve-generator')

// generate samples in a grid of width 300, height 400
const generator = dissolve(300, 400)

// generate first sample
const sample = generator.next()
console.log(sample.value[0], sample.value[1]) // x, y

// generate second sample
generator.next()
console.log(sample.value[0], sample.value[1]) // x, y

// ... will generate a sample for each of the 300 * 400 points in the domain

API:

require('dissolve-generator')(Number width, Number height) => Generator<Tuple<Number x, Number y>>

Note that each sample the returned generator yields is a 2-element array (x,y tuple).

Demo

There is a demo which visualizes the algorithm under the demo/ folder.

Citation

This effect was originally created by Mike Morton, appearing in the first volume of the classic Graphics Gems series.

A Digital Dissolve Effect by Mike Morton "Graphics Gems", Academic Press, 1990

License

MIT (c) Travis Fischer 2016

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