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+ - Book Review: Core HTML5 2D Game Programming->

Submitted by eldavojohn
eldavojohn (898314) writes "Core HTML5 2D Game Programming details a journey through creating Snail Bait in well defined steps. This simple two dimensional platform game works as a great starting point for anyone interested in making their very first game targeting many desktop and mobile platforms. This incremental process is expertly segmented into logical lessons with the only prerequisite being fluency in JavaScript. One of the most attractive aspects of this book is that the core concepts of this book don’t rely on some flavor of the week JavaScript library or framework.

author David Geary
pages 615 pages
publisher Prentice Hall
rating 9/10
reviewer eldavojohn
ISBN 9780133564242
summary An exercise in 2D game development and mechanics in HTML5 and JavaScript.

First, this book isn't for people who do not recognize HTML5 and JavaScript as a valid development platform for games. I know you’re out there, you can stop reading here and move on to the next article. This book isn't for you. If you have no programming experience this book is likely not for you either. This book dives into concepts faster than Geary’s last book on game development in Canvas. You should also be familiar with JavaScript if you want to effortlessly start on this book. Throughout the book, Geary utilizes object’s JavaScript prototypes to add functions, uses anonymous functions and refers to common programming patterns.

It is worth repeating that the implementation in this book does not rely on a framework or library that could change or go defunct. The game runs entirely on code covered in the book accessing W3C standard specifications like requestAnimationFrame(). As long as JavaScript interpreters don’t change core things like timing control, this book should be relevant to developers for years to come.

The reason this book gets a nine is it accomplishes everything it sets out to do and Geary does a great job dividing up task after incremental task of setting sprite sheets and backgrounds into motion. The reason it doesn't get a ten is that I was personally disappointed with the the author devoting little time to physics and their simulations.

The book is laid out to enable its use as two kinds of resources: cover to cover and chapter specific topics. Reading this straight through, there were only a few times where it felt like I was needlessly being reminded of where I had already read about tangential topics. On the plus side if you ever want to see how Snail Bait implemented something like sound, you need only spend time on the chapter devoted to sound sprites. One mild annoyance I had with the text was that the author seems to always refer to Snail Bait as “Snail Bait” which leads to a Ralph Wiggum-like aversion to pronouns or saying “the game” instead occasionally. It might only be me but it can become tiresome to read “Snail Bait” five or six times on the same page.

You can read a sample chapter here that shows how to implement sprite behaviors.

The first two chapters of the book focus on a set of basic guidelines to follow when doing game development in HTML5 and JavaScript — like keeping certain UI display elements in CSS instead of rendering them as paths or objects in the Canvas. Geary also covers the very absolute simplest concepts of how graphics are going to be displayed and how the background is going to move. He also spends time in Chapter Two showing how to best set up the development environment. It is demonstrated how shortening your cycle of deployment saves you tons of time and the author does a great job on letting you know what tools to use to debug throughout the whole text.

The third chapter delves into draw and rendering graphics in the canvas as well as introducing the reader to the game loop. It spends a good amount of time explaining the use of animation frame control in a browser to keep animations running smoothly. It also begins the auditing of frame rates so that the game can respond to and display things normalized at the rate the user is experiencing them. It also touches on how parallax can be employed to show things closer up moving faster than those further back in the background. This illusion of depth has long been popular and is even finding its way into scrolling on blogs and I wish that Geary would have spent more time on this perhaps in a later chapter but offer the reader more on how to do multiple levels of depth.

The next chapter tackles the core infrastructure of Snail Bait and discusses at length encapsulation of certain functionalities (instead of globals) in the source code as well as Snail Bait’s 2300 line prototype. It bothers me that one file is 2300 lines and I wish there was a better way to do this but as a learning tool, it works even if it is daunting to scroll through. The book adds some helpful pointers about how utterly confusing the “this” keyword can be in JavaScript. Chapter Four really sets the pace for the rest of the book by introducing the use of event listeners and illustrating how the game loop is going to continually be extrapolated.

The next three chapters cover the use of loading screens, sprites and their behaviors. Snail Bait uses all its graphics from an open source game (Replica Island). But if you were to design your own graphics for your game, these chapters do a great job of showing how to construct sprite sheets and how to use tools to construct metadata in the code so that the sprites are usable by the sprite artists. Using the flyweight pattern, Geary sets the stage for more complex behaviors and actions to come in the following chapters.

The next three chapters cover time, stopwatches and their effects on motions and behaviors within the game. The author starts and works from linear motion to non-linear motion and then using transducer functions to affect the time system. The game now has bouncing coins, a jumping player and Geary does a good job of showing the reader how to emulate behaviors in the code.

Naturally what follows next is collision detection and gravity. The collision detection strategies were adequate but I wish that there was more depth at least referenced in the text. This isn't a simple problem and I did like how Geary referenced back to chapter two’s profile and showed how collision detection performance as you implement and refine and optimize your algorithm. The nice thing about this book is that it often tackles problems with a general solution in the code (runner/sprite collision) and then provides the edge case solutions.

In the fourteenth chapter, the author tackles something that has long been a plague in HTML5 games: sound and music. The author doesn't sugarcoat this citing the long history of problems the vendors have had trying to support this in browsers. There’s a great explanation of how to create and handle “sound sprites” (similar to sprite sheets) so that there is only one download for background music and one download for audio sprites.

Next Geary covers the problem of multiple viewport sizes with a focus on mobile devices. Of course this is one of the biggest issues with mobile gaming today. The chapter is lengthy and deals with the many intricacies of scaling, sizing and touch events. This chapter is long but the highly detailed support of multiple platforms and resolutions is a justified discussion point.

In sixteen, the reader gets a treatment of utilizing sprites and their artists to simulate sparks and smoking holes. The book calls this chapter “particle systems” but I don’t think that’s a very good title as the code isn't actually dealing with things at the particle level. Instead this chapter focuses on using sprites to simulate those behaviors via animation. This is completely necessary on a computation inexpensive platform but it is misleading to call these particle systems.

Now that the game looks and functions appropriately, the book covers UI elements like player scores and player lives. The auditing of these metrics are covered in the code as well as warnings when the game begins to run to slowly. It also covers the ‘edge’ condition of winning in the game and the routine that is followed when the user wins the game.

The next chapter introduces the concept of a developer backdoor so that the reader can manually speed up or slow down the game while playing it or even test special cases of the runner sprite interacting with other elements. It’s a useful trick for debugging and playing around but does devote a lot of time to the specialized UI like the speed slider and other things that won’t (or rather shouldn't) be seen by a common player.

Chapter nineteen really felt out of place and very inadequate on important details. It’s a blind rush through using node.js and to implement server side high scores. The way it’s implemented would make it trivial for someone to submit a high score of MAX_INT or whatever to the server. The metrics reporting is done in a manner that (in my opinion) breaks from long established logging structure one would be familiar with. While it covers important things to record from your users in order to tweak your game, the inadequacy of discussions about shortcomings makes it feel out of place in this text. It's a topic of great depth and I have no problem with an author touching on something briefly in one chapter — this chapter does lack the warnings and caveats found in other chapters though.

Contrary to the previous chapter, the final chapter is a fast application of the entire book’s principles applied to a new game (Bodega’s Revenge). Geary gives a final run through showing how the lengthy prior discussions quickly translate to a new set of sprite sheets and game rules. If this book is ever expanded, I think it would be great to include additional chapters like this although I would pick a more distinct and popular two dimensional game format like a tower defense game or a bejeweled knockoff.

Overall, Core HTML5 2D Game Programming is a great book for a JavaScript developer looking to dabble in game development. You can purchase Core HTML5 2D Game Programming from Slashdot welcomes readers' book reviews (sci-fi included) — to see your own review here, read the book review guidelines, then visit the submission page. If you'd like to see what books we have available from our review library please let us know."

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Comment: Re: Maybe if Adobe fixed their broken updater... (Score 2) 203

by slaker (#48928549) Attached to: Adobe's Latest Zero-Day Exploit Repurposed, Targeting Adult Websites

Run this command from the named Administrator account:
@powershell -NoProfile -ExecutionPolicy unrestricted -Command "iex ((new-object net.webclient).DownloadString(''))" && SET PATH=%PATH%;%ALLUSERSPROFILE%\chocolatey\bin

Add this to the machine startup script or acceptable alternative of your choosing.
choco install flashplayeractivex
choco install flashplayerplugin

Flash is now less retarded.

Also, the site for direct download of Flash installers is:
And the sad thing is I typed that shit out from memory because it is etched in my brain at this point.

Comment: No. (Score 5, Insightful) 227

by eldavojohn (#48923389) Attached to: Facebook Censoring Images of the Prophet Muhammad In Turkey

To be fair to Zuckerberg and Facebook, the company must obey the law of any country in which it operates.

No. He came out in support of a universal maxim and then went back to his board who showed him X dollars of income they get by operating in Turkey. Just like the revenue lost when Google left mainland China. Instead of sacrificing that revenue to some other social network in Turkey run by cowards, he became a coward himself in the name of money. It is an affront to the deaths and memory of the Charlie Hebdo editors. His refusal could have worked as leverage for social change in Turkey but now it will not.

So no, your statement isn't fair to Zuckerberg and his company and the platinum backscratcher he gets to keep with "TURKEY" inscribed on it. Fuck that greedy bastard and his petty meaningless lip service.

+ - Valve's Economist Yanis Varoufakis Appointed Greece's Finance Minister->

Submitted by eldavojohn
eldavojohn (898314) writes "A turnover in the Greek government resulted from recent snap elections placing SYRIZA (Coalition of the Radical Left) in power — just shy of an outright majority by two seats. Atheist and youngest Prime Minister in Greek history since 1865 Alexis Tsipras has been appointed the new prime minister and begun taking immediate drastic steps against the recent austerity laws put in place by prior administrations. One such step has been to appoint Valve's economist Yanis Varoufakis to position of Finance Minister of Greece. For the past three years Varoufakis has been working at Steam to analyze and improve the Steam Market but now has the opportunity to improve one of the most troubled economies in the world."
Link to Original Source

Comment: Rumor: Fox Is Planning an X-Files Revival (Score 1) 477

by eldavojohn (#48904215) Attached to: Best 1990s Sci-fi show?
In the news recently are rumors that Carter, Anderson and Duchovny will reunite for new X-Files episodes. Fox has sorta confirmed this.

I own all the DVDs, a couple years ago I rewatched them. I may come off as a rabid fan at times but the background music was atrociously horrid. Also the story arc plot became overly convoluted and impossible to explain at times. That said, one of the most convoluted characters (Krycek) was my favorite. Aside from several minor valid criticisms like that, I really think it's a great platform for modern storytelling.

I do have to ask myself, at times, if there is some level of insane conspiracy theory today that we owe at least in part to those people watching X-Files when younger. I have to admit that the 9/11 inside job truthers movement claims could have been ripped from the pages of an X-Files script.

My biggest concern, of course, is whether or not it could still be fresh. With recent high quality additions to television canon, we'd have to be prepared for Chris Carter coming back at us with a 90's angle when episodes like Home really aren't as shocking anymore. The bar has been raised (thankfully).

Right now, The X-Files is going to occupy a contextual place in television history like The Twilight Zone. A revival could very well tarnish that. On the other hand, I've never felt like I really received closure on the whole story arc ...

Comment: Re:Where Does He Stand On the Issues? (Score 4, Interesting) 120

by slaker (#48900403) Attached to: Fark's Drew Curtis Running For Governor of Kentucky

To be honest, most of the politics tab trolls (GaryPDX, HellBentForLeather, Bevets) have up and left or been banned and a lot of the former right-wing true believers with a shred of integrity (Weaver95, HubieStewart) of now have pinned some form of "I'm not a republican, I'm a libertarian" badge on in its place. Fark's Politics tab is mostly moderates and left-of-center types condemning republican talking points and making fun of the obvious trolls. That MIGHT change as we move closer to election season, but I think those with truly opposing viewpoints have scuttled off to Reddit or Freeperland.

Comment: Re:Awesome, I shall buy one in a year (Score 3, Interesting) 114

by slaker (#48880855) Attached to: NVIDIA Launches New Midrange Maxwell-Based GeForce GTX 960 Graphics Card

You might be able to find a Geforce 750 for $125 or so. They're adequate but definitely not ideal for 1920x1080 in most PC games. They're also ridiculously efficient; they don't even need an extra PCIe power connection.
If anyone tells me they want to game on a PC and don't immediately mention a game with a more serious demand, that's the hardware I use.

I generally prefer ATI hardware because I think nVidia's stock cooling kills graphics cards and I'd rather deal with crappy drivers, but the current ATI hardware is a complete non-starter. There's really no level at all where it can be justified.

Comment: Re:Sad to hear (Score 2) 314

by Ford Prefect (#48823549) Attached to: Radio Shack Reported To Be Ready for Bankruptcy Filing

Probably useless for most people reading this, but my favourite-ever electronics store must be the utterly one-off R. F. Potts in Derby, UK. The shop is absolutely tiny, but chock-full of stuff both new and old - with incredibly helpful and knowledgeable staff. Weird, obscure component is buggered, and you need a new one? Hand it over, and they'll find a replacement from the wall of drawers behind the counter - then charge you something like 20p for it. They also have a wide range of old computer parts and random reclaimed mechanisms from things - one of their front windows is always filled with inspiration for stuff to build.

It's probably Derby's engineering heritage that allows it to keep going - with Rolls Royce aero engines and Bombardier trains based nearby, there must be plenty of engineers mucking around with stuff in their spare time...

I only wish they'd open a branch in Seattle, where I live now! A trip to a Radio Shack a few years ago for components was most disappointing.

Programmers used to batch environments may find it hard to live without giant listings; we would find it hard to use them. -- D.M. Ritchie