How to convert a string to a boolean (the right way)

There are a couple of ways to convert a string variable to a boolean variable in Javascript. However, when doing this, you have to be kind of careful: it’s kind of easy to mess up this sort of logic and doing it wrong can result in some nasty bugs. So, in order to save you a headache or two, I’ve detailed how to do it properly in this article. Read on, if you’re interested.

1) You might be tempted to say if(myString)…

…and this would appear to work, for a while. However, it’s really the wrong way to go about this. Observe…
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For loops, while loops, fruit loops…

There are a lot of different kinds of ways to write loops in Javascript. You have your standard for loop and while loop, but beyond that you have the do-while loop, the object properties loop, and lots of different variation of all four “basic” loops. In this post, we’ll examine the four basic loops, the reverse for loop, the reverse while loop, the short reverse while loop, object property loops, and more. I’ll also explain a bit about loop unrolling and where/how it can help you optimize your code. Read on, if you dare!

The classic for loop

What I like to call the classic for loop is perhaps the most basic of all loops in Javascript. It looks like this…
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jetx app.

7 Cool JavaScript Expressions You Should Never Use

I think we can all agree that JavaScript is a pretty cool language. And as with many things, some bits of JavaScript are cooler than others. However, the cool-ness of a piece of JavaScript code is by no means synonymous with its practicality. In fact, one might go so far as to say that the coolness of a JavaScript statement is an inverse measure of how often it should be used. That is, the cooler the code is, the less you should use it.

And if that’s the case, then you should never, ever use anything you see in this article, because from here on out you will be exposed to some Seriously Cool Code.

1) Truncating numbers with bitwise operators

You can use bitwise operators to truncate numbers, like so…
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How to Round Numbers To Arbitrary Values

This is just a quick little function I find pretty useful. It allows you to round any number to an arbitrary value, and can be useful for when you’re working with and rendering to a grid or want a slider that increments by a certain step…
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Field of view in Javascript using recursive shadow casting

Field of view, and stuff

Field of view, which involves determining which tiles are visible to the player, is a particularly fun aspect of writing roguelikes, in my opinion. When writing a field of view algorithm, you often find yourself trading quality for performance, or vice versa. Some algorithms get around this with a bit of trickery, like the Rogue algorithm. Other algorithms have no visible artifacts and in fact are quite pleasing visually, but pay for this with a definite decrease in performance…
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Generating caverns with cellular automata

In this article, I’ll be discussing how to generate neat-looking fully connected caves using cellular automata. This algorithm builds off of another algorithm which can be found here. As noted, the linked algorithm is incomplete and cannot be used for generating dungeons that are suitable for a real roguelike. This article is about the method I used to make that algorithm workable.

First off, the basic algorithm:

To begin, let’s take a look at basic algorithm behind generating nice-looking cave levels with cellular automata…
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Console-like display in the browser?

I’ve been working for some time on a Roguelike in Javascript. One of the first things I had to do for my Roguelike, of course, was establish some sort of display routine. I could have gone with HTML5’s new <canvas> tag or something similar, but setting up a console-like environment for canvas can get a little involved. So instead, I established a way to use the browser’s native text rendering. Say hello to a simple Javascript class for console-like rendering in the browser: I call it display.js.

So, let’s take a look at the code required initialize a basic 80 by 25 console and draw a few characters with the display class…
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Roguelike game programming and development in Javascript?

The Roguelike genre has been in development for decades–since 1980, in fact, when Rogue, the first Roguelike game, was written. Since then, Roguelike games have been created in many different programming languages. Among the more popular of these languages are C, C++, Java, and Python. However, a new contender is appearing: Javascript. Although it’s the new kid on the block, Javascript is quickly becoming a popular choice for Roguelike development and has already been used to make quite a few games…
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8 great A* pathfinding resources

If you’re writing a game that incorporates both a terrain of some sort and enemies that walk around, the chances are you’ll need some version of pathfinding to control the enemy movement patterns. The thing is, pathfinding is serious business–it’s not easy to grasp. To make things worse, there aren’t many good pathfinding resources–most of the articles that turn up on Google and such only serve to confuse you further. That’s why I’ve taken the time to compile this list of pathfinding resources that I’ve found to be actually helpful, as opposed to confusing or just plain wrong.
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A revolutionary and amazing new way to loop through arrays

…well, revolutionary and amazing to me, anyhow. Like most Javascript programmers, I usually use a for loop to iterate through my arrays, a method which typically works pretty nicely and doesn’t really have many drawbacks. However, I recently discovered another method which takes a tad less typing while maintaining the same functionality–the forEach loop. It’s quite handy and you don’t have to declare a bunch of variables to loop through an array.

The forEach loop behaves pretty much like your standard for loop, except that it’s a function that you call only on arrays. It looks like this…
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