In one of my current javascript projects, I have to deal with 3D voxel coordinates. And, sometimes, I have floating points coordinates which must be converted to integers in order to convert them into proper array index.Javascript is a wonderful language, really. However, implementations are sometimes weird, and the way to do something can sometimes have very huge impacts on the performances. Worse, sometimes the classical way is more expensive than the tricky one.So, some people have made performance comparisons on jsperf to check which is the fastest way to do. Most of these tests sa...

Recently I saw somebody asked a question in a forum, the question is "Which programming language should I learn first?". Then someone answered this question. His answer:Depends.To program in an expressive and powerful language: PythonTo get a website up quickly: PHPTo mingle with programmers who call themselves “rockstars”: Ruby.To really learn to program: C.To achieve enlightenment: Scheme.To feel depressed: SQLTo drop a chromosome: Microsoft Visual BasicTo get a guaranteed, mediocre, but well paying job writing financial applications in a cubicle under fluorescent lights: Ja...

The first thing you often hear when talking about JavaScript is often “JavaScript doesn’t have visibility modifiers, hence it doesn’t support private variables”. This is only valid for 50%, because JavaScript indeed doesn’t have visibility modifiers (public, private, friend) but it has closures and function scopes. With these tools we can make variables private. Let’s take the following function:var names = ["Kenneth", "John", "Marc", "Robert"];var lookup = function (index) { return names[index];}alert(lookup(0));As you can see the variable “names&r...

I wrote a README the other day for a project that I’m hoping other developers will look at and learn from, and as I was writing it, I realized that it was the sort of thing that might have intimidated the hell out of me a couple of years ago, what with its casual mentions of Node, npm, Homebrew, git, tests, and development and production builds.Once upon a time, editing files, testing them locally (as best as we could, anyway), and then FTPing them to the server was the essential workflow of a front-end dev. We measured our mettle based on our ability to wrangle IE6 into submission or a...

The HTML5 Microzone is presented by DZone and Microsoft to bring you the most interesting and relevant content on emerging web standards.  Experience all that the HTML5 Microzone has to offer on our homepage and check out the cutting edge web development tutorials on Script Junkie, Build My Pinned Site, and the HTML5 DevCenter. I'm working on a little demo mobile application for an upcoming project, and I wanted to add sliding transitions between pages. Pretty simple, right? You just use jQuery, jQuery Mobile, zepto, or one of a bunch of other frameworks, an...

There are two ways of creating time delays with JavaScript. The first is more simpleand will simply wait for a specified amount of time before executing a function. The seconddoes the same but will repeatedly execute the function.Note, many browsers have a minimum delay length of between 25 and 75 ms, with some of the fastest browsershaving a minimum delay of about 3 ms. If a shorter delay is specified,the actual delay will be the minimum delay length. Even with higher numbers, the delay is never perfect. Mostbrowsers will take slightly longer than the time you ask for, typically just a few mi...

There's nothing like jsconf for bringing out the meta! Since the conference ended two blog posts have created a lot of buzz, at least within my own twitter bubble.First, Rebecca Murphey's JavaScript: It's a Language, Not a Religion. I take Rebecca's post as a cautionary tale about the dangers of hero-worship and the tendency to assume that the people we respect in one sphere share our views in other spheres. I bring it up here not because I want to discuss the content of her post but because I'm ripping off her title.The second blog post was Ryan Funduk's Our Culture of Exclusion. Ryan talk...

Many people get tripped up by the this keyword in JavaScript. I think theconfusion comes from people reasonably expecting this to work like “this”does in Java or the way people use “self” in Python. Although this issometimes used to similar effect, it’s nothing like “this” in Java or otherlanguages. And while it’s a little harder to understand, its behavior isn’tmagic. In fact, this follows a relatively small set of simple rules. Thispost is an explanation of those rules.But first, I want to give some terminology and information about Ja...