Killzone 2 famously used only 60 percent of the PlayStation 3′s latent power, but when Guerrilla finished with Killzone 3, they were hard pressed to fit everything in.
“By the end of Killzone 2, we had a lot of people on the team who were pretty comfortable with [coding for SPU use],” Guerrilla’s Michiel van der Leeuw told Eurogamer’s Digital Foundry, speaking of the Cell processor’s 32 Synergistic Processing Units or SPUs.
“So it was just a natural progression for us to continue using it. We got to the point where they were all full though, so we had to optimise our SPU code quite a bit to fit it all in at the end.”
Van der Leeuw’s comments come in opposition to an earlier statement from managing director Herman Hulst, who said he’d learned a lesson from Killzone 2 to never claim a hardware’s potential had been fully realised.
Guerrilla utilised the Cell’s oft-overlooked SPUs for a number of processing tasks, taking the load off the PS3′s dedicated systems.
Killzone 3′s physics, for example, were optimised in collaboration with Havok to use SPUs rather than the physics processing unit.
Various graphical processes including anti-aliasing were also shifted over, leaving the graphical processing unit free to be pushed in other directions.
The extra processing available in the SPUs also allowed Guerrilla to ramp up the game’s scaling AI.
There’s plenty more good reading through the link above, even if you’re not the techy type.