User Manual

The Nodes > 3D > Texture > Cube Map and Sphere Map nodes can be used to help create
environment maps, applying special processing and transforms to create the cubic or spherical
coordinates needed.
Sphere map example.
To produce reflections with real-time interactive feedback at a quality level appropriate for
production environment maps, you make some trade-offs on functionality when compared with
slower but physically accurate raytraced rendering. Environment-mapped reflections and
refractions do not provide self-reflection or any other kind of interaction between different
objects. In particular, this infinite distance assumption means that objects cannot interact with
themselves (e.g., the reflections on the handle of a teapot will not show the body of the teapot).
It also means that objects using the same cube map will not inter-reflect with each other. For
example, two neighboring objects would not reflect each other. A separate cube map must be
rendered for each object.
The Reflect node outputs a material that can be applied to an object directly, but the material
does not contain an illumination model. As a result, objects textured directly by the Reflect
node will not respond to lights in the scene. For this reason, the Reflect node is usually
combined with the Blinn, Cook-Torrance, Phong, or Ward nodes.
Reflection
Reflection outputs a material making it possible to apply the reflection or refraction to other
materials either before or after the lighting model with different effects.
A Blinn material connected to a
background material input of the
Reflect. This causes the reflection
to be added to the Blinn output.
A Reflect is connected to the Diffuse
Color component of the Blinn, causing the
reflection to be multiplied by the diffuse
color and modulated by the lighting.
Chapter – 76 3D Compositing Basics 1569