2012

Table Of Contents
translucency How light is scattered through an object.
transmittance scale Increases or decreases the amount of energy a transparent
material transmits out to the scene.
transparency A quantity defining how much light is let through an object.
transparent command A command started while another is in progress.
Precede transparent commands with an apostrophe.
two sided material The positive and negative normal of the material will be
considered during the rendering process.
UCS See user coordinate system (UCS).
UCS definition Each UCS definition can have its own origin and X, Y, and
Z axes. Create and save as many UCS definitions as you need.
UCS icon An icon that indicates the orientation of the UCS axes. (UCSICON)
underconstrained geometry Objects with unsolved degrees of freedom are
underconstrained.
underground The XY plane of the user coordinate system when perspective
projection is turned on and when viewed from below ground. The underground
plane displays with a color gradient between the earth horizon (nearest to the
horizon) and the earth azimuth (opposite the horizon). See also ground plane
and sky.
underlay A DWF, or DGN file used to provide visual context in a drawing
file. Underlays cannot be edited, and do not provide the full range of
notification. Underlays cannot be bound to a drawing. See also external
reference (xref).
up direction A vector defining what direction is Up. By default this is the
positive Z axis (0,0,+1).
The up direction and the north direction are always constrained such that
they are perpendicular to each other.
user coordinate system (UCS) The active coordinate system that establishes
the XY plane (work plane) and Z-axis direction for drawing and modeling.
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