User Manual

Blinn
The Blinn material is a general purpose material that is flexible enough to represent both
metallic and dielectric surfaces. It uses the same illumination model as the Standard material,
but the Blinn material allows for a greater degree of control by providing additional texture
inputs for the specular color, intensity, and exponent (falloff), as well as bump map textures.
Phong
The Phong material produces the same diffuse result as Blinn, but with wider specular
highlights at grazing incidence. Phong is also able to make sharper specular highlights at high
exponent levels.
Cook-Torrance
The Cook-Torrance material combines the diffuse illumination model of the Blinn material with a
combined microfacet and Fresnel specular model. The microfacets need not be present in the
mesh or bump map; they are represented by a statistical function, Roughness, which can be
mapped. The Fresnel factor attenuates the specular highlight according to the Refractive Index,
which can be mapped.
Ward
The Ward material shares the same diffuse model as the others but adds anisotropic highlights,
ideal for simulating brushed metal or woven surfaces, as the highlight can be elongated in the U
or V directions of the mapping coordinates. Both the U and V spread functions are mappable.
This material does require properly structured UV coordinates on the meshes it is applied to.
Textures
Texture maps modify the appearance of a material on a per-pixel basis. This is done by
connecting an image or other material to the inputs on the Material nodes in the Node Editor.
When a 2D image is used, the UV mapping coordinates of the geometry are used to fit the
image to the geometry, and when each pixel of the 3D scene is rendered, the material will
modify the material input according to the value of the corresponding pixel in the map.
TIP: UV Mapping is the method used to wrap a 2D image texture onto 3D geometry.
Similar to X and Y coordinates in a frame, U and V are the coordinates for textures on
3D objects.
Texture maps are used to modify various material inputs, such as diffuse color, specular color,
specular exponent, specular intensity, bump map, and others. The most common uses of
texture maps is the diffuse color/opacity component.
The Fast Noise texture used to control the
roughness of a Cook-Torrance material.
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