2012

 An expanded description of the linetype
 A comment such as "Use this linetype for hidden lines"
If you omit the description, do not insert a comma after the linetype name.
A description cannot exceed 47 characters.
Alignment Field (A)
The alignment field specifies the action for pattern alignment at the ends of
individual lines, circles, and arcs. Currently, AutoCAD for Mac supports only
A-type alignment, which guarantees that the endpoints of lines and arcs start
and stop with a dash.
For example, suppose you create a linetype called CENTRAL that displays the
repeating dash-dot sequence commonly used as a centerline. AutoCAD for
Mac adjusts the dash-dot sequence on an individual line so that dashes and
line endpoints coincide. The pattern fits the line so that at least half of the
first dash begins and ends the line. If necessary, the first and last dashes are
lengthened. If a line is too short to hold even one dash-dot sequence, AutoCAD
for Mac draws a continuous line between the endpoints. For arcs also, the
pattern is adjusted so that dashes are drawn at the endpoints. Circles do not
have endpoints, but AutoCAD for Mac adjusts the dash-dot sequence to provide
a reasonable display.
You must specify A-type alignment by entering a in the alignment field.
Pattern Descriptors
Each pattern descriptor field specifies the length of segments making up the
linetype, separated by commas (no spaces are allowed):
 A positive decimal number denotes a pen-down (dash) segment of that
length.
 A negative decimal number denotes a pen-up (space) segment of that
length.
 A dash length of 0 draws a dot.
You can enter up to 12 dash-length specifications per linetype, provided they
fit on one 80-character line in the LIN file. You need to include only one
complete repetition of the linetype pattern defined by pattern descriptors.
When the linetype is drawn, AutoCAD for Mac uses the first pattern descriptor
for the starting and ending dashes. Between the starting and ending dashes,
the pattern dash specifications are drawn sequentially, beginning with the
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