PLT: v1.2 release notes

This release is mostly bug fixes, but there are a few new features.

New features:

- AmigaDOS enviroment variables are now supported instead of Manx enviroment
  variables.  Manx enviroment variables had a problem with initializing the
  enviroment from within a handler.  If Manx's set command was not executed
  before running the handler, the system would crash.

- Two new HP-GL commands, AF and PG, are now supported.  These commands
  cause the page to be dumped, and a new one started.  When output is 
  being sent to the screen, the close box must be clicked to display
  the next page.  PLT: works slightly different because of this.  Before,
  a page would be dumped if anything had been written to the handler,
  regardless of whether or not any lines were actually plotted.  Now,
  PLT: will only dump a page if there are lines to print.

- The number of lines processed is now displayed in the screen title bar
  when output is sent to the screen.  This will let you estimate the amount
  of memory needed to dump the plot to the printer by multiplying the number
  of lines by either 16 or 28, and adding 80-100k.
  
- If output is sent to the screen, the screen is flashed when the plot is
  finished.

- PLT: now sets up the necessary Preference options in it's own copy of
  the preferences.  It does not change the global settings set by the
  Preferences program, only it's own copy.

- An enviroment variable, PltMaxRasHgt, has been added to control the height 
  of each raster.  The default is 64 and the minimum is the height of a
  single strip printed by the driver (Ex. an 8 pin doing only one pass has
  a strip height of 8.  If it does 2 passes, the strip height is 16).
  The enviroment variable sets the maximum height.  The actual height is
  calculated as the largest multiple of the strip height that is less than
  the maximum height.

Bugs Fixed:

- PLT: now parses the pen info string properly.  It was shifting the pen
  thickness over one pen, and sometimes ignoring the last pen.

- The memory-conserve mode now should work properly.  Under certain 
  circumstances, some of the lines would be lost.

- Manx enviroment variable are no longer supported.  They didn't work properly
  anyways. (See above)

- The LB command has been fixed.  It incorrectly updated the pen location.

- DI and DR commands have been fixed.  It didn't allow some directions such
  as DI 0,1

- When the output was sent to the screen, lines were not properly clipped.
  They could go all the way to the edge of the "page", but now they are
  clipped in the correct place.


I've discovered that the StartUp field in the mount list is limited to about
39 characters.  This is enough for a few switches and about 5 pens.  If this
isn't enough for your needs, use the enviroment variable.

Rich Champeaux (rachamp@mbunix.mitre.org)
          also (rchampe@hubcap.clemson.edu) between 8/89 and 5/90

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PLT: v1.1 release notes.

This version has a few new features:

- The status window is now opened when the handler is first written to.
  This allows you to see how many lines have been processed and the 
  amount of free memory left in the system.  The display is updated every
  32 lines.  The status window also has a close box that allows you to
  abort the plot at any time.

- A requester is now opened when the computer runs out of memory.  Everything
  is freed before the requester is opened, since the when PLT: runs out of
  memory, there is less than 28 bytes free in the system.

- A new switch 'M' has been included.  This switch puts PLT: into it's
  Memory Conserve mode.  This mode takes only 16 bytes per line instead
  of 28, but results in a serious performance degradation.  More information
  on this mode can be found in the README file.


There is a known bug in PLT:.  Manx's getenv() function doesn't seem to be
compatable with handlers.  If the 'set' command has not been used before
calling PLT:, the system will crash.  It doesn't matter what variable
has been defined with the 'set' command, just so long as its been called.
I tried calling setenv() to set a dummy variable before calling getenv(),
but it crashed on the setenv().  This means that if your startup sequence
doesn't already use the 'set' command, you must use 'set' or 'SetPltInfo'
to set PLT:'s defaults.

V1.0 didn't handle switches the way I had intended.  All switches after
a '-' were negated.  I guess this was a valid way to do it, but it wasn't
what I intended and it's not the way it does it now.  If you want to
negate both the S and W switches, you must use '-S-W'.

Rich Champeaux  (rachamp@mbunix.mitre.org)