needs-update

   

Typically called (indirectly) by a snip within the buffer to force the buffer to be redrawn.

• (send a-wx:media-buffer needs-update snip localx localy w h) -> void
      snip :  wx:snip% object
      localx : inexact real
      localy : inexact real
      w : inexact real
      h : inexact real

  The localx, localy, width, and height arguments specify the area that needs repainting in the coordinate system of snip.