Sets the dash pattern for stroked lines and curves

  length is the length of the dash. If options is not present,
  or options[:space] is nil, then length is also the length of
  the space between dashes

  options may contain :space and :phase
     :space is the space between the dashes
     :phase is where in the cycle to begin dashing. For
            example, a phase of 0 starts at the beginning of
            the dash; whereas, if the phase is equal to the
            length of the dash, then stroking will begin at
            the beginning of the space. Default is 0

  integers or floats may be used for length and the options

  dash units are in PDF points ( 1/72 in )

Alias for dash

Returns when stroke is dashed, false otherwise

Stops dashing, restoring solid stroked lines and curves