XCONTOUR - X CONTOUR plot of f(x1,x2) via vector plot call

xcontour n1= [optional parameters] <binaryfile [>psplotfile]

X Functionality:
Button 1 Zoom with rubberband box
Button 2 Show mouse (x1,x2) coordinates while pressed
q or Q key Quit
s key Save current mouse (x1,x2) location to file
p or P key Plot current window with pswigb (only from disk files)

Required Parameters:
n1 number of samples in 1st (fast) dimension

Optional Parameters:
d1=1.0 sampling interval in 1st dimension
f1=0.0 first sample in 1st dimension
x1=f1,f1+d1,... array of sampled values in 1nd dimension
n2=all number of samples in 2nd (slow) dimension
d2=1.0 sampling interval in 2nd dimension
f2=0.0 first sample in 2nd dimension
x2=f2,f2+d2,... array of sampled values in 2nd dimension
mpicks=/dev/tty file to save mouse picks in
verbose=1 =1 for info printed on stderr (0 for no info)
nc=5 number of contour values
dc=(zmax-zmin)/nc contour interval
fc=min+dc first contour
c=fc,fc+dc,... array of contour values
cwidth=1.0,... array of contour line widths
ccolor=none,... array of contour colors; none means use cgray
cdash=0.0,... array of dash spacings (0.0 for solid)
labelcf=1 first labeled contour (1,2,3,...)
labelcper=1 label every labelcper-th contour
nlabelc=nc number of labeled contours (0 no contour label)
xbox=50 x in pixels of upper left corner of window
ybox=50 y in pixels of upper left corner of window
wbox=550 width in pixels of window
hbox=700 height in pixels of window
x1beg=x1min value at which axis 1 begins
x1end=x1max value at which axis 1 ends
d1num=0.0 numbered tic interval on axis 1 (0.0 for automatic)
f1num=x1min first numbered tic on axis 1 (used if d1num not 0.0)
n1tic=1 number of tics per numbered tic on axis 1
grid1=none grid lines on axis 1 - none, dot, dash, or solid
x2beg=x2min value at which axis 2 begins
x2end=x2max value at which axis 2 ends
d2num=0.0 numbered tic interval on axis 2 (0.0 for automatic)
f2num=x2min first numbered tic on axis 2 (used if d2num not 0.0)
n2tic=1 number of tics per numbered tic on axis 2
grid2=none grid lines on axis 2 - none, dot, dash, or solid
label2= label on axis 2
labelfont=Erg14 font name for axes labels
title= title of plot
titlefont=Rom22 font name for title
windowtitle=xwigb title on window
labelcolor=blue color for axes labels
titlecolor=red color for title
gridcolor=blue color for grid lines
labelccolor=black color of contour labels ",
labelcfont=fixed font name for contour labels
style=seismic normal (axis 1 horizontal, axis 2 vertical) or
seismic (axis 1 vertical, axis 2 horizontal)


Notes:
For some reason the contour might slight differ from ones generated
by pscontour (propably due to the pixel nature of the plot
coordinates)

The line width of unlabeled contours is designed as a quarter of that
of labeled contours.


AUTHOR: Morten Wendell Pedersen, Aarhus University

All the coding is based on snippets taken from xwigb, ximage and pscontour
All I have done is put the parts together and put in some bugs ;-)

So credits should go to the authors of these packages...

Caveats and Notes:
The code has been developed under Linux 1.3.20/Xfree 3.1.2E (X11 6.1)
with gcc-2.7.0 But hopefully it should work on other platforms as well

Since all the contours are drawn by Vector plot call's everytime the
Window is exposed, the exposing can be darn slow
OOPS This should be history... Now I keep my window content with backing
store so I won't have to redraw my window unless I really have to...

Portability Question: I guess I should check if the display supports
backingstore and redraw if it doesn't (see DoesBackingStore(3) )
I have to be able to use CWBackingStore==Always (other values can be
NonUseful and WhenMapped

Since I put the contour labels everytime I draw one contour level the area
that contains the label will be crossed by the the next contour lines...
(this bug also seems to be present in pscontour)
To fix this I have to redraw all the labels after been through all
the contour calls
Right now I can't see a way to fix this without actually to through
the entire label positioning again....Overkill I would say


The relative short length of the contour segments will propably mask the
cdash settings
which means it is disposable (but I know how to draw dashed lines :)
A way of fixing this could be to get all connected point and then use
XDrawlines or XDrawSegments... just an idea...No idea if it'll work.

I think there is a bug in xContour since my plot coordinates increase
North and west ward instead of south and eastward

I need to check the Self Doc so if the right parameters are described
(I have been through it a couple of times but....)

All functions need a heavy cleanup for unused variables
I suppose there is a couple of memory leaks due to missing free'ing of
numerous pointers (especially fonts,GC's & colors could be a problem...

I have to browse through the internal pscontour call... basically what
I have done is just putting pscontour instead of pswigb... Instead of
repositioning the input file pointer (which doesnt work with pipes) one
should consider the use of temporary file
or write your zoombox to pscontour (...how one does that?)

Wish List:
The use of cgray's unused until now... I guess I'll need to allocate
a gray Colormap -> meaning that the code not will run at other display
than 8 bit Pseudocolor :( (with the use of present version of the colormap
library (code in $CWPROOT/src/xplot/lib ) )

The format of contour label should be open for the user..

It could be nice if one could choose to have a pixmap (like ximage )
underlying the contours... this should be defined either by the input
data or by a seperate file
eg useful for viewing traveltime contours on top a plot of the velocity
field