... Another primary tool used in developing 'God of War III's models and animation is ZBrush. “We use Maya and ZBrush exclusively. Every character and environment artist on the team has a copy of each. We define modeling and asset creation into 2 categories; object based normal maps and tiled normal maps. I think other studio’s call these micro and macro normal maps. We try and create as many assets as we can in ZBrush using object based normal maps. This allows us to create a very high resolution model, transfer the map to an in-game model that looks like the original asset. We want the assets to look as high resolution as possible.

Every character is made with this technique, as well as many parts of the environment. If we use a tiled normal map, we try and stay away from using hard edges. We ask the artists to add extra verts and soft edges so light wraps smoothly around the assets edge. We feel this technique defines what a next gen model should look like. For transferring normal and A.O. maps, we use xnormal, ZBrush and Maya. We model our environments on a grid with a designated vertex per meter ratio and keep to a precise texel ratio to maintain a cohesively mapped environment.”

The lighting system in 'God of War III' is another one of the most noticeable pieces of gorgeous work judging just from the playable builds. “Lighting is very important to the look of 'God of War’s style so it was very important for us to come up with a system that is robust and meets the many needs of the game. We have been working on the lighting since the very start of production, and four years later it’s still something we are tweaking. We wanted to come up with a hybrid system that would meet the demanding needs of the game. For Titan gameplay, we need a fully dynamic lighting solution and for other areas we wanted to use high resolution light maps combined with dynamic lights.”

Choosing either a forward rendering system or a deferred rendering system would always depend on what the game requires and what the game system is capable of. Fortunately, the devs at Sony Santa Monica are extremely happy to be creating a game on a system as powerful as the PS3 and as a result, the rendering was never a choice of one or the other. “We use a combination of both,” says Feldman. “The dynamic shadow system utilizes a deferred rendering solution and the dynamic lighting system uses a forward rendering solution. From the start we wanted the ability to have a lot of dynamic lights. We did not want frame rate to suffer with each light in the scene."

The programmers were able to create a system that allows the artist to use up to 50 lights per game object while not using the graphics processor. All dynamic lighting is done on the PS3’s SPUs. We separate direct light (dynamic lights and baked shadowing light) from indirect (ambient, skylight, bounce). This allows us to merge baked and dynamic shadows by blocking direct light. We use Turtle for baked lighting. After testing a number of different global illumination renderers, we chose Turtle because of its feature set, lua scripting, its speed and the wonderful support offered by the Turtle guys. Turtle gives us the ability to separate direct lightmaps, or direct vertex lighting from indirect. We use all of its global illumination features including final gather. We use image based lighting or skylights and we have the ability to bake ambient occlusion to maps or verts. We also use Turtle light probes (spherical harmonics) as one of our solutions for lighting the characters.”

Probably the most impressive feat in the visuals of 'God of War III' are the in-game facial animations. Kratos now looks more grizzly and menacing having him breath heavily and snarl throughout the game intro and well into the main gameplay. “We animate all of Kratos’ facial animation in-house, and several other main characters as well. For some of the secondary characters, we use Image Metrics’ performance capture system to record the voice actor’s performance and apply the pixel-by-pixel facial changes to the 3D model. Once these are implemented, our animators refine the animations further.”

Bruno Velazquez also chimes in on the animations and rigs. “There have been a series of scripts and tools written to facilitate the creation of biped and quadrupeds rigs as well as facial rigs. These however, were only able to get us so far since every character has its own unique rig. No animations are shared between characters and all have unique sets. Due to the complexity of the characters in the God of War series, we were required to come up with solutions and create special rigs for wings, horse legs, tails, goat legs, and a special rig for the Kratos chains among others.”

Now, does Ken Feldman feel like there is an idea that could have been utilized in 'God of War III? “I tried unsuccessfully to convince Stig to make 'God of War III' a first-person shooter. Kratos could have some truly badass huge weapons that rip gods to shreds. Unfortunately he didn’t see the genius in the idea.” There’s always spin-offs.