Defining UDK

Unreal Development Kit (UDK) is a freely available version of Epic Games, a very popular Unreal game development engine.

First developed in 1998 to power the original Unreal game, the engine (which is C++ based) has gone from strength to strength, and has not only formed the backbone of household-name Epic Games titles, such as the very popular Gears Of War series, but has also been very successfully licensed out to third-party developers. Consequent titles range from Batman: Arkham City to Mass Effect 3, many of which are as equally successful as the games developed by its parent company.

Currently, the Unreal engine itself is in its fourth iteration and is considered to be a top of the range visualization tool. It is not only used in the gaming industry, but has also been used for doing any kind of work that demands real-time computer graphics. UDK uses Unreal Engine 3, but it is still a powerhouse in itself and is quite capable of delivering amazing experiences on iOS software.

The offering of UDK as a concept has evolved from Epic Games content generation tools very early on with Unreal titles; tools which proved to spawn a very healthy and thriving modification (modding) community. Originally, tools like these, such as UnrealEd (the editor tool with which a user can create their own in-game level), were available to anyone who bought the game.

In 2009, however, Epic turned that logic on its head by making their tools available to anybody, whether they owned an Unreal game or not. This proved to be a very successful move which expanded the Unreal developer user base thoroughly.

More recently Epic Games, as part of their constant and persistent updates of UDK, have added iOS functionality (in 2010), making sure that UDK can provide games for the ever-expanding mobile customer base that the iPhone/iPad/iPod Touch devices by Apple introduced. This was first demonstrated to the public by a live tech demo called Epic Citadel; a freely available download on the iTunes store which played like an interactive walkthrough of a medieval town. This attracted a record number of downloads as at that time it was truly groundbreaking to experience high quality real-time graphics on a mobile device. Take a look at the following screenshot:

In fact, although it is not within the scope of this book, very recently certain demos have surfaced highlighting a potential UDK / Adobe Flash Player pipeline, showcasing the very impressive penetration this games development application has made to a number of different platforms.

Of course, we are interested in iOS here, and we’ll be covering that extensively in this book, starting from the bare basics and moving on to some more advanced concepts.

So what is it that we need to know about UDK and its mobile iOS limitations? Does it have any?

Don’t expect to make Gears of War

Let’s start with a fairly realistic statement; we can’t make an AAA gaming title as seen on a contemporary console or PC, such as Gears of War, on iOS using UDK! It is a general limitation of doing mobile development using UDK.

The main reason for this is rather obvious; we just do not have access to the same hardware. The problem is not the software! UDK can deploy the same game on a PC or an iOS device, but it is the end-hardware specification that has the final say in what can be handled in real-time or not.

Mobile devices (and this of course includes iOS devices) have progressed by leaps and bounds over the last few years, and after many false starts mobile gaming today is a force to be reckoned with, both commercially and technologically. That still, however, does not change the fact that as an iOS UDK developer, you will work with more restricted hardware as opposed to, for example, someone developing for an Xbox 360 platform.

Let’s look at this in more detail; these are some of the current iPhone 4S technical specifications:

• 960 x 640 pixel display
• 16 GB, 32 GB, or 64 GB Flash drive
• Dual-core 1 GHz Cortex-A9PowerVRSGX543MP2GPU
• 512 MB RAM

The newest iPad released in early 2012 has the following specifications:

• 2048 x 1056 pixel display
• 16 GB, 32 GB, or 64 GB Flash drive
• Quad-core PowerVRSGX543MP4GPU
• 1 GB RAM

While these specs are fairly impressive compared to both mobile devices of the past, and also the fact that we are talking about what is essentially a pocket gadget, they cannot really compare with the specification of a top-of-the-range gaming PC or even a current generation console.

This, of course, does not mean we can only develop poor or second rate games with UDK. Indeed, some of its contemporary examples highlight the huge potential it has in delivering AAA gaming experiences, even with its current limitations, borne, as described previously, from the hardware limitations of a mobile device.

The best example by far has got to be Chair Entertainment’s and Epic Games’ Infinity Blade, an epic third-person sword-fighting game which came out in late 2010 and is considered the ideal showcase for UDK’s technical prowess on the Apple devices.

Already spawning sequels and with huge commercial success behind it from its iTunes Store business model, Infinity Blade was, and is, a big eye-opener for all aspiring games developers who want to use Unreal engine technology for a successful iOS title with a very modern feel and visuals.

To see just how powerful an iOS game can be, just look at the following screenshot for a fine example: