What has changed from the plotter version V5-beta from Gregory Bond
to this version V6-beta?

- I needed xy-lineplots which scaled against their x-values, not against
  their index in the data array. The xy-lineplots should be drawn using
  different line types (lines, points, line+points, impulses and
  impulses+points), different nicer line styles (solid, dotted, dashed
  and dotdashed), and different marker type for point plots (rectangle,
  diamond a.o.). Therefore I created a new class AtXYPlot with its
  subclass AtXYLinePlot. I the future I need more plot types (3D?)

- I needed logarithmic axes and the possibility to switch between the
  log and lin transformation at runtime. Therefore I create a new
  class AtXYAxis. This class is based on the AtAxisCore class which
  I had to modify for some reasons (more colors, origin line, subgrids
  on every subtic a.o). In the future I need more axis types, e.g.
  polar axes.

- I needed a posssibility to get the pointer position on the plotting
  area and to get a range/rectangle on this area for further zooming.
  All the needed stuff was contained in the earlier version V4 but not
  in V5. Therefore I re-added the code for handling motion and drag
  events to V6-beta with a lot of changes

- I cleaned up the code and the manual pages
- I use OSF/Motif, so I added a larger Motif demo program
- I don't use Wcl, so I removed the Wcl stuff.
- I don't use TeX, so I rewrote the documention using [ntg]roff.

Peter Klingebiel, Thu Jul  2 09:51:50 1992
(klin@iat.uni-paderborn.de)
