A key component in a rendering program is its material shaders.
These shaders are collections of mathematical routines which simulate real-world shading,
lighting, reflections, shadows and other reflective properties. A complete listing of all
the shaders provided with the NuGraf renderer are shown on the backside of the glossy
printed brochure. The shaders have been written to work in tandem to produce perfect
results given the default parameters assigned to each shader; this allows good to perfect
results on first pass renderings without requiring parameter tweaking.
Key features of the shaders are complete control over all color components (ambient,
diffuse, luminous and specular), extensive transparency control (face opacity, specular
opacity, edge opacity and edge fall-off), accurate refraction computation (including the
'fresnel' component for glass effects), Phong or Blinn highlight models, three types of
automatic reflection mapping, and the most complex multi-layer texture mapping system
available in any 3D rendering program (as outlined below).
One of the primary driving forces behind the evolution of Okino's "NuGraf" package has been the desire to have the software import and render 3D scene
files (in their native file formats) directly from such high-end packages as 3DS MAX®,
Lightwave®, SoftImage®, Maya®, trueSpace® and others. This
capability, which has been achieved, allows the software to directly import and render
these 3D data files exactly as they would appear in their native 3D rendering/animation
programs, with no tweaking or parameter modifications necessary. In order to accomplish
this unique feat the NuGraf renderer has had to be continually expanded in order to
accommodate the rendering features of these aforementioned products. As such, the NuGraf
renderer provides much generality and much user control over how the shading and texture
mapping process is to be evaluated on a per-material basis. This is particularly evident
when importing and rendering Lightwave files for which the native Lightwave renderer
allows a bitmap image to modulate any number of shading parameters and for which it allows
one or more of these modulated texture maps to be layered on top of each other - these are
all easily simulated with the NuGraf renderer's shading and texture mapping sub-systems.
