Comparing games can be fun, and there’s really nothing wrong with it when you pitch against one another two games (or two versions of the same game) that have enough in common to be actually comparable.
Unfortunately, though, we often see comparisons based on merely superficial similarities, where the real point hidden behind the surface is simply that the two titles are on rival consoles.
This is exactly the case with Evolution Studios’ Driveclub and Playground Games’ Forza Horizon 2 – behind which the fans of the PlayStation and Xbox camps are currently rallying, ready for the usual fall war.
Both games have cars, and the point of both titles is driving them around. That’s the superficial similarity. The problem is that, despite that, they’re actually extremely different under the hood; and that leads to inevitable big discrepancies on the graphical level.
Unfortunately, the comparison has gone beyond the fans of this or that console, and we’re seeing several media outlets pitching the two games’ graphics against each other, which is quite sad considering that those that write those kinds of articles should know something about how games are actually made.
When I read just another piece showing how this game has better looking environments, or that other game has worse looking weather, I begin to doubt that the necessary technical knowledge is actually there, or if it’s simply taking a back seat to the need of create controversy.
Simply put, before being racing games, technology-wise, Forza Horizon 2 is an open world game, while Driveclub is a racing game based on closed tracks.
That makes all the difference in the world and automatically determines that almost every element of Driveclub‘s graphics will look better than its counterpart on Forza Motorsport 2. It doesn’t depend on a superior engine or on the console they run on. It depends on the very nature of the two games.
We know that the PS4 has a power edge at the moment, but it’s very safe to assume that if the two exclusives were inverted, Driveclub‘s visuals would still be superior, again, due to the way its world is developed.
Games based on closed tracks or levels like Driveclub can afford to load all or a large parts of the assets (models, textures, and so forth) of a track before you start racing. As long as those assets fit the allocated RAM, the only limiting factor is the rendering power of the GPU that needs to keep up with our car as it renders the world around us.
That’s why racing games based on closed tracks tend to have fairly long loading times. While we look at that loading screen for thirty seconds — or even a minute — the hard disk is loading the track’s textures and models in the RAM, and the track is being prepared for us to race on.
In addition to this, closed tracks also tend to be limited to a single location, which pretty much automatically optimizes the assets that need to be used. You won’t have too many different kinds of trees, asphalt, curbs and so forth, because the racing is all done around the same track, within the same location, meaning that the same textures will be reused all over the place.
This means that developers can be relatively liberal with high resolution textures, extremely detailed models, and dazzling effects. To put it down simply, they can make the game look as awesome as the GPU’s rendering power and RAM allow.
Open world games like Forza Horizon 2 don’t have the same luxury as they need to contend with a hidden enemy that many erroneously consider secondary or negligible: the hard disk drive (HDD).
Due to their nature and to the large size of their maps open world games can’t afford just loading the whole world before you play a race, simply because it’d never fit in a console’s memory (large open worlds with modern level of visual fidelity wouldn’t easily fit even if your console had 32 or 64 gigabytes of ram). All those models, textures and visual elements are simply way too big combined to be loaded all at once.
This means that much smaller portions of the map have to be loaded from the HDD into the RAM as we drive into them, and then unloaded and replaced by the next in line as we move past. The pace at which that is allowed happen depends largely on the reading speed of the hard disk.
Above you can see a scheme from a technical presentation focused on inFAMOUS: Second Son, which is one of the most relevant open world games released lately for the PS4. The squares represent portions of the map, called blocks (other developers call them cells). Only 10 of them are rendered and visible at any given time around the character (the ones in green), while an extra seven (the ones in yellow) are loaded in memory in order to anticipate Delsin’s movement and compensate for the slow reading speed of the hard disk.
As Delsin moves, the blocks he leaves behind will be unloaded from the RAM and disappear from the screen, and the blocks in front of him will be loaded from the hard disk into the RAM and rendered when he gets close enough.
The big problem is that console hard disks are slow. Both the PS4 and the Xbox One come packed with 5,400 RPM HDDs, which basically means that they’re veritable slugs. When you buy a hard disk for your PC, it’s pretty rare to find any under 7,200 RPM nowadays (not that it would make that much of a difference. That’s still quite slow).
Sucker Punch’s Adrian Bentley was very candid in admitting in his inFAMOUS Second Son Engine Postmortem panel at GDC that the I/O (Input/Output) speed of the hard disk was a big problem.
The maximum speed reachable by Delsin Rowe when he uses his neon dash power is 20 meters per second. That’s not because of artistic reasons, or due to an arbitrary decision. It’s because if he moved faster the hard disk wouldn’t be able to send the assets to the memory in time and the world around the character wouldn’t be rendered, with pretty disastrous effects like missing textures, distorted models or worse.
While a closed world game has to contend only with rendering the assets already pre-loaded in memory fast enough, minimizing access to the hard disk, an open world has to do that, and also need to load new blocks and unload old ones from the HDD, not only using more hardware resources, but also forcing developers to use smaller and more compressed textures, less complex models and less fancy effects and shaders.
What makes the problem even more relevant for a driving game like Forza Horizon 2 is that the faster we move, the more the issue is amplified. Whether we run at 20 meters per second or 217 mph, all the elements of the world around us still need to be rendered, but they need to be rendered and loaded/unloaded from hard disk to RAM much faster if we move at 217 mph. To do that while avoiding falling behind with rendering and loading/unloading assets, said assets need to be smaller.
I didn’t use the 217 mph figure randomly: it’s the top speed of the Ferrari LaFerrari, which is the fastest car revealed so far for Forza Horizon 2. 217 mph translates in 97 meters per second, which is just south of five times as fast as Delsin.
Driveclub doesn’t have to contend with the same problem, which allows the game to look better. It’s really that simple.
Incidentally, that’s also one of the reasosn why Watch_Dogs is less of a graphical powerhouse than inFAMOUS: Second Son. While both are open world games, Watch_Dogs has cars, meaning that the game needs to render its world and load/unload assets faster than inFAMOUS: Second Son, forcing the developers to use smaller assets to compensate.
In conclusion, Driveclub looks better than Forza Horizon 2 not because the PS4 is more powerful than the Xbox One (that’s pretty much undeniable by virtue of the numbers, but in this case it’s not the primary issue), or because Driveclub‘s engine is better than Forza‘s, or even because the good folks at Evolution Studio are more proficient than those working at Playground Games.
It’s because Driveclub and Forza Horizon 2 are extremely different games under the hood. While they both feature cars and driving, the different design of their worlds require development choices and technologies that are as different as night and day.
Pitching them directly against one another is an exercise in futility that ignores their radical differences, pretty much saying that a F1 Ferrari is better than one built for the streets. They’re both cars. You can drive both and they both come with four wheels and an engine, but they’re designed with opposite philosophies and different technical solutions, to perform completely different tasks, making the comparison simply nonsensical.
Driveclub has been built to enjoy racing on a track while dazzling us with absolutely spectacular visuals. Forza Horizon has been designed to let us lose ourselves in a large, seamless world and allow us to drive anywhere we like. While one inevitably comes with better overall graphics, the other comes packaged with its enormous open world.
They’re not comparable, and they shouldn’t be compared, pretty much like apples to oranges.