Line Endings. Annotations such as lines, polylines and
free text callouts may have line endings such as arrows, circles or
squares.
By default the size of the line ending is proportional to the
width of the line. However ABCpdf allows control over the line end
size using an annotation ABCp_LEScaling entry. This is a second
class custom tag as defined in the PDF Name Registry.
During the generation of the appearance stream this tag can be
used to control the relative size of the line endings. It is legal
for the tag to be left in the PDF so that ABCpdf will continue to
use it for any further updates to the appearance stream.
Alternatively it can be deleted and as long as the appearance
stream is not updated, the line endings will remain the same
size.
The LE entry is used to define line endings. The ABCp_LEScaling
entry parallels the LE entry defining the relative sizes for the
endings defined in the LE entry.
A Line annotation has an LE consisting of an array of two
entries representing the type of finial to be used at the start and
end of the line. In this case the ABCp_LEScaling is an array of two
numbers defining the relative sizes of the start and end
finials.
A Free text annotation functioning as a callout, has an LE entry
consisting of a name representing the final to be used at the end
of the line. In this case the ABCp_LEScaling is a number defining
the relative sizes of the finial.
Positive numbers represent a scale factor - so two would
indicate an ending twice the normal size. Negative numbers can be
used to indicate absolute values so in this context negative two
would represent an ending with a size of two points. The default
value if you provide a null entry is one - no scaling.
You can set these values using simple ABCpdf calls such as
doc.SetInfo(annot.ID, "/ABCp_LEScaling", "[-2 0.5]") and
doc.SetInfo(annot.ID, "/ABCp_LEScaling:Num", "-2").
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