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Glossary
Commands associated with definitions are shown in parentheses at the end of
the definition.
absolute coordinates Coordinate values measured from a coordinate system’s origin
point. See also origin, relative coordinates, user coordinate system (UCS), world coordi-
nates, and world coordinate system (WCS).
acquired point In the tracking or object snap tracking method of locating a point, an
intermediate location used as a reference.
acquisition marker During tracking or object snap tracking, the temporary plus sign
displayed at the location of an acquired point.
adaptive sampling A method to accelerate the anti-aliasing process within the bounds
of the sample matrix size. See also anti-aliasing.
affine calibration A tablet calibration method that provides an arbitrary linear
transformation in two-dimensional space. Affine calibration requires three calibration
points to allow a tablet transformation that combines translation, independent X and Y
scaling, rotation, and some skewing. Use affine calibration if a drawing has been
stretched differently in the horizontal or vertical direction. (TABLET)
alias A shortcut for an AutoCAD command. For example, CP is an alias for COPY, and
Z is an alias for ZOOM. You define aliases in the acad.pgp file. For a list of command
aliases, see “Command Aliases” in the Command Reference.
aliasing The effect of discrete picture elements, or pixels, aligned as a straight or curved
edge on a fixed grid appearing to be jagged or stepped. See also anti-aliasing.
aligned dimension A dimension that measures the distance between two points at any
angle. The dimension line is parallel to the line connecting the dimension’s definition
points. (DIMALIGNED)
ambient color A color produced only by ambient light.