Grand Theft Auto 5's PC RT enhancements hint at GTA 6 features

Grand Theft Auto 5 on PC has finally received the RT upgrades to achieve feature parity with the current generation console versions, almost three years since they arrived on Xbox and PlayStation consoles. The wait was worth it as scalability is impressive and the game also includes the ability to toggle ray traced global illumination – which may well hint at the kind of RT features we can expect to see in the upcoming Grand Theft Auto 6.

To begin with though, let’s be realistic. GTA 5 is almost 12 years old now and as such, there are limits as to how much better the game can actually look. The original was built around the fundamental constraints of the Xbox 360 and PlayStation 3, after all, and that still shines through today, even in the maxed out PC experience. Character models are of their era, while material and texture quality is nowhere near as impressive as modern releases. GTA 5 comes from a time before the games industry switched to techniques like physically-based art pipelines and shading maths. Ray tracing can still transform the game in many respects, but not to the extent of making it comparable to a brand-new triple-A release.

Even so, the upgrades are welcome. Pre-RTGI GTA 5 is a game that suffers from a problem that many games without RTGI have – and especially ones from this era. Indirect lighting in the original is handled in an interesting way, however. According to investigations by Adrian Courrèges, the game generates a cubemap from the player camera position in real-time, similar to many racing games. This gives the game approximate real-time reflections on elements like cars, and for rougher surfaces the game appears to use a filtered version of that to make it so shadows are not pitch black. The problem is that lighting is only represented from one angle and as such, all shadowed areas in GTA 5 tend to look grey or overly dark. Everything in sunlight tends to be shaded a greyish light or almost blue colour and where the edges of geometry are adorned with a thick halo of screen- space ambient occlusion.

Ray traced global illumination – not available in the current-gen console versions, remember – is a game-changer here, with light bounce around the environments of a far, far superior quality. To say it really lightens up the mood is almost an understatement: bounce lighting you get from the sun and the indirect shadows you get as a result dramatically alter the game’s look – and it is always for the better.