Max httnn

httnn / debugComponentUpdate.js

Created June 24, 2019 07:47

	const updateReason = fn =>
	function(prevProps, prevState) {
	const isEqual = (a, b) => {
	if (a === null \|\| b === null \|\| a === undefined \|\| b === undefined) {
	return a === b;
	} else if (a.constructor === Object && b.constructor === Object) {
	const keysA = Object.keys(a).sort();
	const keysB = Object.keys(b).sort();
	if (keysA.join(',') === keysB.join(',')) {
	return keysA.every(key => isEqual(a[key], b[key]));

httnn / weightedrandom.js

Created July 24, 2017 06:37

	const slots = [50, 40, 200, 300, 400].sort((a, b) => a < b);
	const slotSum = slots.reduce((sum, s) => sum + s, 0);
	const random = () => {
	const r = Math.random() * slotSum;
	for (let i = 0, c = 0; i < slots.length; i++) {
	c += slots[i];
	if (r < c) {
	return i;
	}
	}

httnn / example.js

Created January 19, 2017 12:34

MobX: pattern for updating data when other data changes?

	class Store {
	constructor() {
	reaction(
	() => [this.filter, this.limit, this.order],
	() => this.getItems()
	);
	this.getItems();
	}

	@observable filter = '';

httnn / waveforms.html

Last active December 2, 2021 10:00

Drawing waveforms with the Web Audio API

	<!DOCTYPE html>
	<html lang="en">
	<head>
	<meta charset="UTF-8">
	<title>Waveform drawer</title>
	</head>
	<body>
	<input type="file" /><br />
	<svg preserveAspectRatio="none" width="2000" height="100" style="width:900px;height:50px;" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
	<linearGradient id="Gradient" x1="0" x2="0" y1="0" y2="1">

httnn / matches.js

Created July 22, 2015 09:12

fuzzy searching with JavaScript

	var matches = function(string, q) {
	q = q.toLowerCase().replace(/[^\w]/g, '');
	var inner = function(string, q) {
	if (q.length) {
	var i = string.indexOf(q[0]);
	return i > -1 ? inner(string.substr(i), q.substr(1)) : false;
	}
	return true;
	};
	return inner(string.toLowerCase(), q);

httnn / gist:a6ab15cbba9c82a5065d

Created April 9, 2015 16:28

Calculate average color of Android Bitmap

	/*
	pixelSpacing tells how many pixels to skip each pixel.
	If pixelSpacing > 1: the average color is an estimate, but higher values mean better performance
	If pixelSpacing == 1: the average color will be the real average
	If pixelSpacing < 1: the method will most likely crash (don't use values below 1)
	*/
	public int calculateAverageColor(android.graphics.Bitmap bitmap, int pixelSpacing) {
	int R = 0; int G = 0; int B = 0;
	int height = bitmap.getHeight();
	int width = bitmap.getWidth();

httnn / gist:b1d772caf76cdc0c11e2

Created April 9, 2015 16:23

Calculate brightness of Android Bitmap

	/*
	Calculates the estimated brightness of an Android Bitmap.
	pixelSpacing tells how many pixels to skip each pixel. Higher values result in better performance, but a more rough estimate.
	When pixelSpacing = 1, the method actually calculates the real average brightness, not an estimate.
	This is what the calculateBrightness() shorthand is for.
	Do not use values for pixelSpacing that are smaller than 1.
	*/
	public int calculateBrightnessEstimate(android.graphics.Bitmap bitmap, int pixelSpacing) {
	int R = 0; int G = 0; int B = 0;
	int height = bitmap.getHeight();