Question: Is it difficult to add some solid or hollow points in the graph plotted?

Actually I reach that in mathematica not easy,

Show[Plot[
  Piecewise[{{0, x < -0.5}, {1/5, x < 1.3}, {2/5, x < 1.7}, {3/5,
     x < 2}, {4/5, x < 2.8}, {1, x > 2.8}}], {x, -2, 5},
  Ticks -> {{-0.5, 1.3, 1.7, 2, 2.8}, {1/5, 2/5, 3/5, 4/5, 1}},
  PlotStyle -> {Thickness[0.01]}],
 ListPlot[{{-0.5, 1/5}, {1.3, 2/5}, {1.7, 3/5}, {2, 4/5}, {2.8, 1}},
  PlotStyle -> PointSize[0.03]]]

Show means show several graphs combined and with the specified options added.

what's that in maple?the same fuctional thing.

Show[Plot[
  Piecewise[{{0, x < -0.5}, {1/5, x < 1.3}, {2/5, x < 1.7}, {3/5,
     x < 2}, {4/5, x < 2.8}, {1, x > 2.8}}], {x, -2, 5},
  Ticks -> {{-0.5, 1.3, 1.7, 2, 2.8}, {1/5, 2/5, 3/5, 4/5, 1}},
  PlotStyle -> {Thickness[0.01]}],
 ListPlot[{{-0.5, 1/5}, {1.3, 2/5}, {1.7, 3/5}, {2, 4/5}, {2.8, 1}}, 
  PlotMarkers -> {"\!\(\*
StyleBox[\"\[EmptyCircle]\",\nFontFamily->\"ºÚÌå\",\n\
FontWeight->\"Plain\"]\)"}, Filling -> Axis, FillingStyle -> {Red}]]

But I'm not satisfied with the picture above,for the EmptyCircles is not so fit with the line simultaneously

"PlotMarker" is another interesting function is mathematica 7,I don't know if there is something similar in maple

 the pictures below are I found in wikipedia.

 Is there some other methods to generate some satisfactory graphs? with maple or mathematica(I haven't ask the question in mathematica related forums or their mail group)