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Light Properties
Affects how lights behave when calculating indirect illumination. By default,
the energy and photon settings apply to all lights in a scene.
Photons/Light Sets the number of photons emitted by each light for use in
global illumination. Increasing this value increases the accuracy of global
illumination, but also increases the amount of memory used and the length
of render time. Decreasing this value improves memory usage and render time,
and can be useful for previewing global-illumination effects.
Energy Multiplier Multiplies the global illumination, indirect light, intensity
of the rendered image.
Visual
Helps you understand why the renderer is behaving in a certain way.
Grid Renders an image that shows the coordinate space of objects, the world,
or camera.
■ Object. Shows local coordinates (UVW). Each object has its own coordinate
space.
■ World. Shows world coordinates (XYZ). The same coordinate system applies
to all objects.
■ Camera. Shows camera coordinates, which appear as a rectangular grid
superimposed on the view.
Grid Size Sets the size of the grid.
Photon Renders the effect of a photon map. This requires that a photon map
be present. If no photon map is present, the Photon rendering looks just like
the nondiagnostic rendering of the scene: the renderer first renders the shaded
scene, then replaces it with the pseudocolor image.
■ Density. Renders the photon map as it is projected into the scene. High
density is displayed in red, and lower values render in increasingly cooler
colors.
■ Irradiance. Similar to the Density rendering, but shades the photons based
on their irradiance. The maximum irradiance is rendered in red, and lower
values render in increasingly cooler colors.
BSP Renders a visualization of the parameters used by the tree in the BSP
raytrace acceleration method. If a message from the renderer reports excessively
1652 | Chapter 18 R Commands