GDC 2016: Nvidia thinks its latest offering takes games closer to reality

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Nvidia has updated its GameWorks software development kit with three new tools designed to help developers make games look more life-like than ever before.

If you've played games such as GTA V on newer Nvidia GPUs in recent years, you've no doubt noticed GameWorks-related graphics options such as Percentage Closer Soft Shadows (or PCSS) — used to render soft shadows — in settings menus.

Unveiled at GDC 2016, GameWorks SDK 3.1 introduces new rendering techniques for lighting and shadows. First used in Fallout 4, Volumetric Lighting simulates how light behaves as it scatters through their air.

In a conference call with journalists, Nvidia senior director of GameWorks Rev Lebaradian said that in the past, "Computer graphics generally ignored the matter that exists within air between the viewer and the various surfaces in the scene, assuming there's a vacuum everywhere, ignoring the light scattering effect that's within a volume."

By using a multi-stage algorithm, he said that the technique helps developers, "Get closer to doing a more accurate simulation of what actually happens when light travels through a medium that has matter in it."

In the shadows

The second new technique, Hybrid Frustrum Traced Shadows (HFTS), was introduced in The Division. It uses an algorithm to draw high-fidelity shadows that transition from hard to soft as they move further away.

According to Lebaradian, HFTS incorporates elements of PCSS and helps solve, "One of the most fundamental and difficult problems in computer graphics."

He added: "A lot of things we show you may look subtle but are key in what seems to trigger the concept of realism in people's brains, and shadows play a key role in whether we see something as fake or not."

The third technique, Voxel Accelerated Ambient Occlusion (VXAO), was first used in Rise of the Tomb Raider. It uses shading to add depth and realism to scenes by calculating shadows using all of the scene's surrounding geometry, as opposed to geometry visible to the camera.

Nvidia has also added to capabilities to its Nvidia PhysX library. PhysX-GRB helps improve performance in games that feature hundreds of thousands of bodies in a scene by offloading compute from the CPU to the GPU. The other, Nvidia Flow, is an algorithm used to simulate combustible fluids such as fire and smoke.