From: maurice@cs.monash.edu.au (Maurice D Castro)
Subject: Re: MS-Windows version
Organization: Computer Science, Monash University, Australia
Date: Tue, 13 Oct 1992 00:31:23 GMT


cgh6m@darwin.clas.Virginia.EDU (Craig G. Hocker) writes:
>
>I appreciate the work of those that port programs to different
>environments, but may I ask exactly what is the point of porting
>gnuplot to MS-Windows if it is still limited to 64K like the DOS version?
>
>Here I sit with a new DX2 and 8MB of RAM thinking I would no longer
>have to upload large files to the SPARC and use X11 gnuplot and up
>pops the old DOS line. Well, nice try but I guess it's back to the 
>UNIX world for me.
>
>Craig Hocker
>NSF Center for Biological Timing
>cgh6m@virginia.edu
>University of Virginia, Charlottesville, VA 22901
>

Craig,
	There were 2 major reasons for porting gnuplot to the MS-Windows 
environment.
		1. Added Functionality
		2. Added Memory

1. Functionality

The MS-Windows version provides:
	* Access to all the graphics printers supported by MS-Windows.
	* A menu based interface in addition to the command line interface
	* Cut and paste facilities into Windows clipboard (useful if you
	  are using a Windows based wordprocessor.

2. Memory.

I freely admit that the MS-Windows environment still has the 64K segment
limit - under most circumstances. There are 2 strategies which have been
employed to avoid this limitation:
	* dividing data structures
	* use of fast huge pointers (non-normalized)

In many cases it was possible to divide datastructures into smaller components.
An example of this is the bitmap used for driving dotmatrix and inkjet 
printers. Instead of declaring a pointer to a single array to contain all 
the bitmap data (this must be less than 64K in size to work under 
MS-Windows), an array of pointers to the rows of the bitmap is used, 
limiting a row to 64K size. 

For datastructures which could not be divided in a sensible manner we 
employed non-normalized huge pointers. These can point at objects which
are larger than 64K in size.

The MS-Windows port of gnuplot has increased a critical limitation 
present on the DOS version: Total Memory Allocation. Gnuplot under
MS-Windows has access to 16Mbytes of memory, not the 640Kbytes available 
under DOS.


In conclusion the MS-Windows port provides significant advantages over
the MS-DOS port. 

There is still a remenent of gnuplot's DOS heritage in the MS-Windows port 
in the form of 64K maximum individual object size. This limitation has been
dealt with by either breaking up objects or using special large objects.

At this point may I second Russell Lang's statement that gnuplot for
MS-Windows is a test release, and that as such we need help fixing the
problems. 
--
Maurice Castro                 |  "In hardware engineering, Ohm's
maurice@bruce.cs.monash.edu.au |   law and Maxwell's equations pale
                               |   in importance and influence next
                               |   to Murphy's Law" Gordon Bell
x-gateway: rodan.UU.NET from info-gnuplot to comp.graphics.gnuplot; Fri, 16 Oct 1992 10:51:11 EDT
Subject: Installing gnuplot3.2 on a sun Sparc2
Date: Fri, 16 Oct 1992 08:49:13 -0600
From: dw929591@longs.lance.colostate.edu (Darren Weibler)
Newsgroups: comp.graphics.gnuplot