ABCpdf uses the standard Adobe PDF coordinate space. The origin
of this space is at the bottom left of the document. Distances are
measured up and to the right in points. Points are a traditional
measure for print work - there are 72 points in an inch.
Please note that the bottom-up PDF coordinate space is
different from the top-down coordinate system often used in
Windows. It means that everything is based around the bottom left
of objects - not the top left. If you wish to use a
different coordinate system you can use the document Units, TopDown or Transform to
accomplish this.
ABCpdf uses the XPoint object to represent
positions in space. It uses the XRect object to represent areas
like the current drawing area or the size of a page.
The Doc.Rect
property is probably the most important property to be aware of.
Virtually everything happens within the Doc.Rect. If you add
text to a document it is added within the Doc.Rect. If you paint or
frame a rectangle it is done within the Doc.Rect. If you add an
image it is scaled to fit exactly within the Doc.Rect.
The default document size for ABCpdf is 612 by 792. This equates
to a physical page size of 8.5 by 11 inches.
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