Introduction

While 64-bit processors have been on the market for quite some time now, the rest of the industry has been slow to catch up. Microsoft’s 64-bit variant of Windows XP was delayed over a year while they focused on enhancing the security of current 32-bit copies of Windows XP. As a result, this gave other hardware manufacturers an excuse to put off their 64-bit driver rollouts.

But with the release of Windows XP x64 Edition late last month, the 64-bit era can finally really take off. One of the first gaming applications that has been released to take advantage of 64-bit Windows is CryTek’s 2004 hit shooter, Far Cry.

64-bit port or 64-bit design?

Before we delve into 64-bit Far Cry however, we wanted to clear up a few common misconceptions enthusiasts may have over 64-bit support. The most common of these is that 64-bit Windows will somehow allow your applications to run faster, the “bigger is better” mentality applies here right? Wrong. Just because you have a 64-bit OS doesn’t mean your 32-bit apps will run faster, in fact some may run slower in a 64-bit environment: some 16-bit applications ran terribly in Windows NT. Fortunately Microsoft has taken steps to ensure that the 64-bit transition is a smooth one, early benchmarks indicate that the performance impact of running a 32-bit app in Windows x64 is only barely distinguishable from running the same application in 32-bit Windows XP.

Another, more subtle misunderstanding relates to so-called “64-bit” apps. These applications may be truly built from the ground up for 64-bit, or may merely be 32-bit software that has been recompiled to run in 64-bit Windows. In other words, just because you have a 64-bit executable doesn’t ensure that the application is truly designed to take advantage of 64-bit hardware and software.

If you recall the original Athlon 64 launch nearly two years ago, Crytek, along with Epic Games (with 64-bit Unreal Tournament 2003) were the first two proponents of AMD’s 64-bit platform and 64-bit gaming in general, with 64-bit Far Cry and Unreal Tournament 2003 both used as technology demos for AMD’s 64-bit platform. In our interview with CryTek CEO Cevat Yerli we were told “We’ve done it [64-bit Far Cry] mainly for content development creators and mod creators, there will be huge benefits from it. For the gameplay it will be more beneficial to the environment, you will have some specific content for 64-bit. There will be a 64-bit version of Far Cry, a separate one eventually. That will be essentially content-wise slightly improved over the 32-bit version but it’s not something which, I mean people with the 32-bit version can still compare to the 64-bit version, but it’s optimized for the 64-bit experience.” He then went on to say that they were focusing on enhancing the visuals for the 64-bit version of Far Cry rather than performance: “Well you will have a better experience, not necessarily “the look”; well you will have more environmental objects. If you consider that a better “look”, then yes, but the experience will be better because more things will be happening on screen.”

Epic was just as forthcoming about their 64-bit port of Unreal Tournament. In our interview with Tim Sweeney on the topic, Tim stated “Our goal in porting UT2003 to 64-bit was to show that it can be done without much work, that the platform is stable, and that it's ready for gaming. We're not doing anything that really takes advantage of over 4 gigs of RAM or the large virtual address space.

The next generation of the Unreal engine is where we'll be taking major advantage of 64-bit in a very visible way, in the 2005 timeframe. We expect to support 32-bit and 64-bit clients and servers for gameplay, but might require 64-bit for content creation, because of the significant requirements of our new content development tools.”

In other words, what we’re telling you today is not to rush out and buy 64-bit hardware and software expecting a massive difference, as even early AMD-64 supporters CryTek and Epic have been quite frank in their 64-bit implementations. We’re basically looking at ports here guys, nothing next-generation that really shows the benefits of 64-bit.

Now with that being said, in some cases the greater registers provided by 64-bit can net performance gains as memory accesses are reduced, in addition as Cevat mentioned CryTek has also added some unique content to 64-bit Far Cry. Let’s go over these changes…