ContourPlot.app

     Contour Plot object and application with color fills.
     OS requirement: Release 3.0 or later.
     Version: ContourPlot Version 1.4MAB [io]

     [Archive Maintainer, please put this into the 3.0 Source Code directory.]

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ContourPlot.app demonstrates the use of object class ContourView, but
at the same time it tries to be a usable application for generating
contour plots WITH COLOR FILLS from 2-dimensional grid data.
While I have seen many contour plot routines and programs that produce
contour lines in color, I could not find any that could FILL regions
inside contour paths.  Hence, the ContourView class and this application.
It can only handle 2-D data on a regularly spaced Cartesian grid.

ContourPlot reads 2-D grid data files in a simple ASCII format which
may be generated easily by other programs.  See the Info/Help Panel
and a sample data file for details of the file format.

* Press  File -> Open Sample File on the menu for a demo plot.

* Press  File -> View Sample File on the menu to look at the data
  file that generates the demo plot.

Plots may be copied to the pasteboard as EPS (Encapsulated PostScript)
by clicking the plot area once and pressing  Edit ->  Copy on the menu.
Then, the plot may be pasted into documents that accept PostScript
data, such as NeXTMail Compose window (In NeXTMail mode), Edit document
(in RTF mode), ohter drawing/layout apps. 

To save to an EPS file, press File -> Save to EPS File on the menu.





From ContourView README.
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     Distinguishing features of this ContourView class are:
     [1] It does color fills within contours just like colored geological maps.
	 As far as I am aware, this is the only public domain source code that can
	 do this for PostScript, not as bitmaps. (Let me know if you know of
	 any other PD code that does color-filled contour plots.)
     [2] It is a pretty self contained object in the form of a View subclass.
     [3] Generated plot may be saved to an EPS file.
     [4] PostScript may be copied onto pasteboard and pasted into other apps that
	 accept EPS data.  Try pasting it into Yap document, NeXTmail compose
	 window, Edit RTFD document, etc.

     There is really no documentation.  Look at the class implementation file
     ContourView.m and an example test application ContourPlotApp.m for usage
     information.  The app included here is just for testing ContourView
     class.  ContourView is meant to be included in your apps like any other
     objects.

     It is pretty easy to use.  If instantiated within IB, all you need to do
     to get a plot is to call the following two method to get a default
     plot.  If you understand the following method, you can use the
     ContourView object easily.

     - setCartesianGridData:(float *)f :(float)xmin :(float)xmax
				  :(float)ymin :(float)ymax
				  ofSize:(int)nx :(int)ny
				  withInterpolationTo:(int)n1x :(int)n1y;
 
    f[nx*ny] is a 1-d array containing 2-d grid data such that f[iy*nx+ix]
    contains the value at (ix, iy).
    Typicall, just 3 messages below will produce a contour plot with color
    fills.

    [contourView setCartesianGridData: fdata :1.0 :5.0 :1.0 :5.0
				ofSize: 20 :20
				withInterpolationTo: 50 :50];
    [contourView setFillEnable:YES];
    [contourView display];

    -------------------------------------------------------------------------------
    TO USE:
    ContourView class consists of the following modules/files.  Other files are
    the glue needed for the test application ContourPlot.app.  When incorporating
    ContourView into your app, you need to copy only the follwoing to your
    project directory:

	ContourView.h
	ContourView.m	  (Class implementation)
	computeContour.m  (contour path computation engine)
	contour.h
	sortContour.c	  (sorting of contour path based on inclusion relation)
	splin2.c	  (bicubic spiline)
	splin2.h

    -------------------------------------------------------------------------------
    TO COMPILE:

    When all the files are ready, you can build the whole application from
    the ProjectBuilder application, or typing "make" from Terminal in this
    directory.



    This can use a lot more optimizations which should speed up the drawing
    significantly.  Some of these are:
    [1] All parameter changes currently trigger recomputation of all contour paths,
	because almost everything is done in drawSelf:: method.
	This should not be necessary for some.  E.g., changing fill colors, line
	width etc should not cause recomputation of contour paths.
    [2] Use DoUserPath() etc to optimize drawing.
    [3] Some methods are not yet implemented (It does what I wanted now).
    -------------------------------------------------------------------------------
    Send comments, bug reports, suggestions and improvements to below:

---
Izumi Ohzawa, Ph.D.            [ $@Bg_78^=;(J ]
USMail: University of California, 360 Minor Hall, Berkeley, CA 94720
Telephone: (510) 642-6440     Fax:  (510) 642-3323
Internet: izumi@pinoko.berkeley.edu (NeXT Mail OK)
