code: def _get_markobj(self, x, y, marktype, marksize, markcolor, markwidth):
          
          if marktype == 'circle':
              obj = self.dc.Circle(
                  x=x, y=y, radius=marksize, color=markcolor, linewidth=markwidth)
          elif marktype in ('cross', 'plus'):
              obj = self.dc.Point(
                  x=x, y=y, radius=marksize, color=markcolor, linewidth=markwidth,
                  style=marktype)
          elif marktype == 'box':
              obj = self.dc.Box(
                  x=x, y=y, xradius=marksize, yradius=marksize, color=markcolor,
                  linewidth=markwidth)
          else:  # point, marksize
              obj = self.dc.Box(
                  x=x, y=y, xradius=1, yradius=1, color=markcolor,
                  linewidth=markwidth, fill=True, fillcolor=markcolor)
  
          return obj
docs: Generate canvas object for given mark parameters.