[Mapserver-users] question about symbols

[Doug Cates]

Hi,

I have a question after reading the SYMBOL page at:

http://mapserver.gis.umn.edu/doc40/mapfile-reference.html#symbology

I'm wondering about the hot-spot of the symbol. Are the symbols centered
on the point, or is the 0,0 position of the symbol placed at the point?

For example, I would think that the following would make a symbol that
was centered on its point:

SYMBOL
  NAME "triangle"
  TYPE vector
  FILLED true
  POINTS
    2 2
    0 -2
    -2 2
    2 2
  END
END

.... and this symbol would be be offset with its lower left triangle
point at the position of the geometry:

SYMBOL
  NAME "triangle"
  TYPE vector
  FILLED true
  POINTS
    4 4
    2 0
    0 4
    4 4
  END
END

If so, it appears that negative points have special meaning and can't be
used to describe a symbol, or to position it properly. Am I
misunderstanding how this works?

Doug
-- 
Doug Cates
Moxi Media Inc.
757 - 1641 Lonsdale Avenue
North Vancouver, BC, Canada V7M 2J5
Phone:  604-984-8109
Fax:    604-608-4764
E-mail: doug at moximedia.com
Web:    www.moximedia.com