INTIALGAP does not work for AGG with patterns of more than one element

[havatv]

INITIALGAP was recently introduced in #3879 for advanced styling of lines. It seems to work well with points (using GAP) and with patterns with only one dash. However, when more dashes are added to the pattern, things get screwed up with AGG (Cairo seems to give OK results). Here is an example mapfile that will demonstrate the problem (image attached):

MAP
  SIZE 570 390
  IMAGETYPE png   # gif|png|jpeg|wbmp]
  #IMAGETYPE pdf
  EXTENT 0 0 95 65
  UNITS meters
  LAYER  # Line overlay - 2
    STATUS DEFAULT
    TYPE LINE
    FEATURE
      POINTS
        5 45
        25 50
        45 50
        35 45
      END # Points
    END # Feature
    CLASS
      STYLE
        COLOR 0 0 0
        WIDTH 16
        PATTERN 40 20 20 20 10 20 END
      END # STYLE
      STYLE
        COLOR 209 66 0
        WIDTH 12
        INITIALGAP 2
        PATTERN 36 24 16 24 6 24 END
      END # STYLE
    END # CLASS
  END # LAYER
END # MAP

[havatv]

png that shows the output of the provided map file

[tbonfort]

fixed in r12732