Anim8or has an integrated Ray Tracer. You can use it to render
movies and still images just like to original scanline renderer and
OpenGL shader renderer. ALl you need to to is select it from he
Renderer->Renderer command dialog.
Ray Tracing is a global rendering technique for making relatively realistic images from 3D models. It traces the path that a light ray might take through the scene to discover what objects, lights, etc. affect the final color of a pixel. It is called a global technique because any part of the scene may influence to final value of any pixel. Ray tracing borrows from optics to model reflections, refractions and more.
Anim8or's ray tracer can render all of it's normal materials, of course. But it also can show reflections off of shiny objects and defraction through transparent ones. The next sections will explain how to add these effects to your images.
|You enable the additional capabilities of ART materials by
adding certain attributes to
normal materials. Attributes allow you to associate arbitrary
values with a material. The ART renderer check them when
initializing a scene and chooses alternate rendering code when the
right ones are present. You add attributes to a material by
clicking on the "Attributes" button in the basic Material Editor.
This section lists the main categories of ART materials.
|The attribute class
is the starting point for accessing ART materials. class is a string attribute which
defaults to normar Anim8or materials when not present. Note that
case is important in attribute names. Class and CLASS are names for different
attribuites and do not affect ART rendering. In addition to the
normal parameters of Anim8or materials, individual classes may use
additional attributes for more flexibility.
The main classes are anim8or (the default), glossyreflector, transparent and dialectric. Each is described in a following section.
|Class anim8or has additional attribute, specular. It determines the
look of the specular reflection. There are 3 recognized values:
|Here is the Anim8or project for the above image: class_anim8or.an8
|This glossyreflector class is a simpler
class that is similar to the anim8or
class with the specular
attribute of glossy.
While the anim8or class is a
little less accurate from a physical sense, glossyreflector attempts to follow
the rules of physics a little more closely.
The glossy reflector class uses the Phong roughness value for the degree of glossiness. glossyreflector has one attribute:
|Here is the Anim8or project for the above image: class_glossyreflector.an8|
|The transparent class is a simple model
for defraction of light through transparent materials. There is
also a slight reflection off the surface. The amount of
transparency is set with the normal transparency
value for a material. It has one additional attribute:
The image below show 5 spheres with and IOR of 1.0, 1.1, 1.2, 1.3 and 1.5, and a transparency of 0.1:
|Here is the Anim8or project for the above image: class_transparent.an8|
|The dielectric class is a complex model
that is closer to how light interacts with real transparent
materials. It uses Fresnel equations to determine reflections and
transmission parameters at each ray-surface interaction. As light
travels through a dielectric material it is attenuated and gradually
takes on the material's color. Thin sections appear almost
colorless but thick sections can be quite dark. Glass is a
dielectric which explains why a solid glass door looks clear from the
front but looking into the edge can be dary green or gray. The diaelectric class has two additional
|Here is the Anim8or project for the above image: class_dielectric.an8|
|You can modify the look of area lights by changing the way
that they are sampled with the following attribute on the light in a
|This image was made with 16 samples per pixel.
Increasing the number of samples will make the images smoother.
Here is the project for this image: light_samplers.an8
|More material classes are coming to Anim8or's ART ray tracer. Stay tuned!|
|This page was last updated on January 5, 2009.||
Copyright 2009 R. Steven Glanvlle