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CAL Snap modes
Snap mode Abbreviation
INSERT INS
INTERSECTION INT
MIDPOINT MID
CENTER CEN
NEAREST NEA
NODE NOD
QUADRANT QUA
PERPENDICULAR PER
TANGENT TAN
The following example uses the Center and Endpoint Snap modes in a CAL
expression:
(cen+end)/2
CAL prompts for a circle or arc and an object. It then determines the midpoint
between the center of the circle or arc and the end of the selected object.
Using the Midpoint Snap mode, in the following example CAL prompts for
an object and returns a point 1 unit in the Y direction from the midpoint of
the selected object:
mid+[,1]
The following example uses the Endpoint Snap mode to calculate the centroid
of a triangle defined by three endpoints:
(end+end+end)/3
Convert Points Between UCS and WCS
Normally, the program assumes all coordinates to be relative to the current
UCS. The following functions convert points between UCS and WCS.
u2w(p1)
Converts point p1 expressed in the current UCS to the WCS.
198 | Chapter 5