6 MAXIMUMPC JANUARY 2007
H
uman and animal skin is one of the most
difficult textures to render because of
the way it both absorbs and reflects
light. Some light is reflected off the surface
of skin, but much passes through the first few
layers, bounces around at irregular angles,
and then re-emerges. The phenomenon is
known as sub-surface scattering, and it’s
notoriously difficult to render because in the
real world, the light that re-emerges is tinted
by the blood in the dermis.
Most lighting models are designed for
hard surfaces and don’t take sub-surface
scattering into account. The fact that DirectX
10’s Shader Model 4.0 supports immensely
complex shader routines, coupled with its
vision of a unified architecture in which all
of the GPU’s shader-processing units can be
dedicated to either pixel, vertex, or geometry
shading will enable developers to create
extremely sophisticated lighting models.
Note the realistic depiction of the skin
and eyes in the star of Nvidia’s “Froggy” demo.BETTER-LOOKING SKIN TEXTURES
New lighting models will deliver heightened realism
T
here’s currently no DirectPhysics API
in DX10, but we expect game devel-
opers will make extensive use of
Direct3D 10’s support for geometry shaders
and its stream output features (discussed
elsewhere in this story) to deliver highly
realistic physics in their games.
Relic Entertainment’s Company of
Heroes is already a shining example of a
game with destructible environments, and it
makes terrifi c use of physics. Relic’s upcom-
ing DirectX 10 patch promises to render the
game even more realistic, with shrapnel and
other particles fl ying everywhere.
If Ageia winds up folding its tent, it
won’t be because of DirectX 10, but in spite
of it: There’s nothing in DX10 that would
prevent a game from executing physics
routines on Ageia’s PPU should developers
decide to go down that path. The problem is
that we’ve seen precious little movement on
the accelerated physics front.REALISTIC PHYSICS
People, animals, and objects will display complex movements
NVIDIA’S FROGGY DEMOCOMPANY OF HEROESNEXT-GEN GAMING