SHOWME is a C program which uses the X Window library to display triangulations and meshes.
SHOWME was developed for use with the TRIANGLE program (which produces Delaunay triangulations, Voronoi diagrams, and finite element meshes). Since data input is done through files with a simple format, it is easy for other programs to generate output that SHOWME can display. SHOWME can also make PostScript graphics files of the images that it displays.
SHOWME can produce documentation online. Complete instructions for invoking the program are available with the `-h' switch:
showme -h
The instructions are long; you'll probably want to pipe the output to more or redirect it to a file. If the program is invoked with no arguments, it prints a short list of command options.
SHOWME can read and display a number of computational objects. The simplest form is a Planar Straight Line Graph (PSLG), which is usually stored in a POLY file. This file contains a list of points, line segments, and possibly some information about holes.
If you are interested in meshes, then a collection of these is available in TEST_MESH, and may be output in POLY format for display by SHOWME.
Try out SHOWME on the sample file, A.poly:
triangle -p A.poly
showme A.poly &
SHOWME will read the Planar Straight Line Graph defined by A.poly, and write its constrained Delaunay triangulation to A.1.node and A.1.ele. SHOWME will display the figure defined by A.poly. There are two buttons marked "ele" in the window; click on the top one. This will cause SHOWME to load and display the triangulation, if it has been computed by TRIANGLE.
For contrast, try running
triangle -pq A
Now, click on the same "ele" button. A new triangulation will be loaded;
this one having no angles smaller than 20 degrees.
To see a Voronoi diagram, try this:
cp A.poly A.node
triangle -v A
Click the "ele" button again. You will see the Delaunay triangulation of the points in A.poly, without the segments. Now click the top "voro" button. You will see the Voronoi diagram corresponding to that Delaunay triangulation. Click the "Reset" button to see the whole diagram.
MDDISK is a C program which displays a molecular dynamics simulation of a fluid as a collection of soft disks, using X Windows and Motif.
PLTMG_SINGLE is a FORTRAN77 program which carries out a finite element calculation, and uses the X Window library for display.
POLY is a file directory which contains a description and examples of the POLY file format.
TRIANGLE is a C program for computing Voronoi diagrams and Delaunay triangulations, and creates and manipulates files that can be displayed by SHOWME.
XFIRES is a C program which simulates the occurrence of fires in a forest, and displays the status of the forest using X Windows.
XGED is a C program which can edit graphs visually; it uses the X Window library to display the graph, and to detect the user's input.
XISING is a C program which simulates the variation in ferromagnetism in a material, displaying the results using X Windows.
XWAVES is a C program which simulates the behavior of solution of certain forms of the wave equation, displaying the results using X Windows.
X Window is a graphics library which must be included in order to build a copy of SHOWME.
Jonathan Shewchuk,
Computer Science Division,
University of California at Berkeley,
Berkeley, California, 94720-1776,
jrs@cs.berkeley.edu.
A is a set of data defining the outline of a capital letter A. Files you may copy include:
square_circle_hole is a set of data defining a square region, with a circular hole, filled up with CVT points. Files you may copy include:
You can go up one level to the C source codes.
