image and binary data file

[Daniel J S. <dan...@ie...>]

The second patch is a major redo of the image and binary data file
support code:

694789 New plotstyle "with pixels"
[Now called "with image"]

with_image_103003.diff.gz
datafiles.tar:
     blutux.rgb
     scatter2.bin
     sine.bin
     using.bin
     demo.edf

The gzip file is the actual patch.  The datafiles.tar file is several
binary data files required for the "image.dem" demo program
within the patch.

Petr and I really winnowed the features, syntax, etc. on this one.
I think we have a nice set of commands and capabilities.
Discussion is always welcome, of course.

Some significant changes are that it is now 'with image' and
'with rgbimage' as opposed 'with pixels".  Also, the variable
'pixelplanes' is defunct.  No longer is there the ability to control
the individual size of pixels.  I thought that would find very little
use, and there are other ways of doing this.  Instead the image
plotting routine has been generalized for any orientation and
skew of image grid.  It will use the efficient term->image function
if appropriate.  Images can be used in both `plot` and `splot`.  But
RGB images cannot be used in `splot`.  [Perhaps a future
discussion item.]

 From Petr's original discussion list submission about binary
data file syntax, I've done some major changes that make the
use of such files much easier.  A concept of "inherent sampling
array" has emerged to make things easy to remember and no
longer is there the arcane use of 0, -1 and -2 in the `using` string.
Instead, associated with `binary` is `array=1024x1024`.  There
are similar options for controlling data position, spacing, translation,
etc. which include `origin, center,  dx, dy, dz, flipx, flipy, flipz,
transpose, flip, scan, rotation, perpendicular, endian, filetype`.  It
may all seem like a lot to digest, but if you try the patch and
look through the demo commands, I think you will find it makes
a great deal of sense.

Petr has written some code for reading EDF files which
we've incorporated into the code and demo script.  The general
strategy is that the binary feature has a structure describing
details about the binary file in question.  (Of course,
that is what is filled in by options like 'origin, center`, etc.)  The
EDF file function looks at a file's header and fills in the necessary
variables of the structure and lets Gnuplot continue onward.

The binary data seems to work fine through a pipe, i.e., `-`.
(One of the original reasons for the patch.)  Actually, I just tried
it one day and it worked without alteration.

I guess it doesn't pay to go into more on this until people have
had a chance to look at the patch.  I suggest some of the developers
give the demo `image.dem` a try.  (I think you will like some of the
capabilities.)  Then generate some discussion about integration
into CVS.  I'm sure many people will have comments and suggestions
about syntax, etc.  But I think that is better tackled through all
developers having the ability to modify code.  It has become a bit
unwieldy for me to make modifications.  My supporting utilities
are becoming out of date and I think most things that need fine tuning
aren't worth addressing until there is some discussion and agreement
on details.  I'm certainly willing to help with changes down the road,
of course.  I've tried not touching the current behavior of Gnuplot, e.g.
`binary` without a <binary list> still behaves like Gnuplot's current
binary mode.

Dan


-- 

Dan Sebald
email: daniel . sebald @ ie ee . o rg
URL: ht tp://acer-access.c om/~dsebald @ acer-access.c om/