Update Triangle to version 1.4. Add some installation notes in the README.

Triangle/Makefile

-# $Id: Makefile,v 1.8 2002-05-18 16:31:17 geuzaine Exp $
-#
-# Makefile for "libGmshTriangle.a"
-#
-# If yours is not a Unix system, use the -DNO_TIMER switch to eliminate the
-#   Unix-specific timer code.
-#
-# If you are modifying Triangle, I recommend using the -DSELF_CHECK switch
-#   while you are debugging.  Defining the SELF_CHECK symbol causes
-#   Triangle to include self-checking code.  Triangle will execute more
-#   slowly, however, so be sure to remove this switch before compiling a
-#   production version.
-#
-# If the size of the Triangle binary is important to you, you may wish to
-#   generate a reduced version of Triangle.  The -DREDUCED switch gets rid
-#   of all features that are primarily of research interest.  Specifically,
-#   defining the REDUCED symbol eliminates the -i, -F, -s, and -C switches.
-#   The -DCDT_ONLY switch gets rid of all meshing algorithms above and beyond
-#   constrained Delaunay triangulation.  Specifically, defining the CDT_ONLY
-#   symbol eliminates the -r, -q, -a, -S, and -s switches.  The REDUCED and
-#   CDT_ONLY symbols may be particularly attractive when Triangle is called
-#   by another program that does not need all of Triangle's features; in
-#   this case, these switches should appear as part of "TRILIBDEFS" below.
+# $Id: Makefile,v 1.9 2003-02-10 23:07:05 geuzaine Exp $
 
 CC     = gcc
 AR     = ar ruvs
 RM     = rm
 RANLIB = ranlib
+RMFLAGS = -f
 
 LIB = ../lib/libGmshTriangle.a
 
-# Do not optimize Triangle: it fucks up on Linux
-RMFLAGS = -f
+# Do not optimize: it crashed on Linux
 CFLAGS  = -O0 $(OS_FLAGS) -DTRILIBRARY
 
 SRC = triangle.c

Triangle/README

+
+If you want to use Jonathan Shewchuk's Triangle as an alternative
+isotropic 2D mesh generator in Gmsh, please download Triangle from the
+author's web site at http://www.cs.cmu.edu/~quake/triangle.html,
+unpack the archive and copy the two files triangle.c and triangle.h in
+this directory. Then run configure and rebuild Gmsh.
+
+Note that by doing so, you agree to Triangle's licencing requirements
+stated below. (Most notably, you can only redistribute the software if
+no compensation is received.)
+
+==============================================================================
+
 Triangle
 A Two-Dimensional Quality Mesh Generator and Delaunay Triangulator.
-Version 1.3
-
-Show Me
-A Display Program for Meshes and More.
-Version 1.3
+Version 1.4
 
-Copyright 1996 Jonathan Richard Shewchuk
-School of Computer Science
-Carnegie Mellon University
-5000 Forbes Avenue
-Pittsburgh, Pennsylvania  15213-3891
-Please send bugs and comments to jrs@cs.cmu.edu
+Copyright 1993, 1995, 1997, 1998, 2002 Jonathan Richard Shewchuk
+2360 Woolsey #H
+Berkeley, California  94705-1927
+Please send bugs and comments to jrs@cs.berkeley.edu
 
 Created as part of the Archimedes project (tools for parallel FEM).
 Supported in part by NSF Grant CMS-9318163 and an NSERC 1967 Scholarship.
 There is no warranty whatsoever.  Use at your own risk.
 
 
-Triangle generates exact Delaunay triangulations, constrained Delaunay
-triangulations, and quality conforming Delaunay triangulations.  The
-latter can be generated with no small angles, and are thus suitable for
-finite element analysis.  Show Me graphically displays the contents of
-the geometric files used by Triangle.  Show Me can also write images in
-PostScript form.
+Triangle generates exact Delaunay triangulations, exact constrained
+Delaunay triangulations, Voronoi diagrams, and quality conforming Delaunay
+triangulations.  The latter can be generated with no small angles or large,
+and are thus suitable for finite element analysis.  Show Me graphically
+displays the contents of the geometric files used by Triangle.  Show Me can
+also write images in PostScript form.
 
 Information on the algorithms used by Triangle, including complete
 references, can be found in the comments at the beginning of the triangle.c
@@ -47,135 +54,3 @@ part of a commercial system is permissible ONLY BY DIRECT ARRANGEMENT
 WITH THE AUTHOR.  (If you are not directly supplying this code to a
 customer, and you are instead telling them how they can obtain it for
 free, then you are not required to make any arrangement with me.)
-
-------------------------------------------------------------------------------
-
-The files included in this distribution are:
-
-  README           The file you're reading now.
-  triangle.c       Complete C source code for Triangle.
-  showme.c         Complete C source code for Show Me.
-  triangle.h       Include file for calling Triangle from another program.
-  tricall.c        Sample program that calls Triangle.
-  makefile         Makefile for compiling Triangle and Show Me.
-  A.poly           A sample data file.
-
-Triangle and Show Me are each a single portable C file.  The easiest way to
-compile them is to edit and use the included makefile.  Before compiling,
-read the makefile, which describes your options, and edit it accordingly.
-You should specify:
-
-  The source and binary directories.
-
-  The C compiler and level of optimization.
-
-  Do you want single precision or double?  Do you want to leave out some of
-  Triangle's features to reduce the size of the executable file?
-
-  The "correct" directories for include files (especially X include files),
-  if necessary.
-
-Once you've done this, type "make" to compile the programs.  Alternatively,
-the files are usually easy to compile without a makefile:
-
-  cc -O -o triangle triangle.c -lm
-  cc -O -o showme showme.c -lX11
-
-On some systems, the C compiler won't be able to find the X include files
-or libraries, and you'll need to specify an include path or library path:
-
-  cc -O -I/usr/local/include -o showme showme.c -L/usr/local/lib -lX11
-
-However, on other systems (like my workstation), the latter incantation
-will cause the wrong files to be read, and the Show Me mouse buttons won't
-work properly in the main window.  Hence, try the "-I" and "-L" switches
-ONLY if the compiler fails without it.  (If you're using the makefile, you
-may edit it to add this switch.)
-
-Some processors, possibly including Intel x86 family and Motorola 68xxx
-family chips, are IEEE conformant but have extended length internal
-floating-point registers that may defeat Triangle's exact arithmetic
-routines by failing to cause enough roundoff error!  Typically, there is
-a way to set these internal registers so that they are rounded off to
-IEEE single or double precision format.  If you have such a processor,
-you should check your C compiler or system manuals to find out how to
-configure these internal registers to the precision you are using.
-Otherwise, the exact arithmetic routines won't be exact at all.
-Unfortunately, I don't have access to any such systems, and can't give
-advice on how to configure them.  These problems don't occur on any
-workstations I am aware of.  However, Triangle's exact arithmetic hasn't
-a hope of working on machines like the Cray C90 or Y-MP, which are not
-IEEE conformant and have inaccurate rounding.
-
-Triangle and Show Me both produce their own documentation.  Complete
-instructions are printed by invoking each program with the `-h' switch:
-
-  triangle -h
-  showme -h
-
-The instructions are long; you'll probably want to pipe the output to
-`more' or `lpr' or redirect it to a file.  Both programs give a short list
-of command line options if they are invoked without arguments (that is,
-just type `triangle' or `showme').  Alternatively, you may want to read
-the instructions on the World Wide Web.  The appropriate URLs are:
-
-  http://www.cs.cmu.edu/~quake/triangle.html
-  http://www.cs.cmu.edu/~quake/showme.html
-
-Try out Triangle on the enclosed sample file, A.poly:
-
-  triangle -p A
-  showme A.poly &
-
-Triangle 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.
-Show Me will display the figure defined by A.poly.  There are two buttons
-marked "ele" in the Show Me window; click on the top one.  This will cause
-Show Me to load and display the triangulation.
-
-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 full extent of the diagram.
-
-------------------------------------------------------------------------------
-
-If you wish to call Triangle from another program, instructions for doing
-so are contained in the file `triangle.h' (but read Triangle's regular
-instructions first!).  Also look at `tricall.c', which provides an example.
-
-Type "make trilibrary" to create triangle.o, a callable object file.
-Alternatively, the object file is usually easy to compile without a
-makefile:
-
-  cc -DTRILIBRARY -O -c triangle.c
-
-------------------------------------------------------------------------------
-
-If you use Triangle, and especially if you use it to accomplish real
-work, I would like very much to hear from you.  A short letter or email
-(to jrs@cs.cmu.edu) describing how you use Triangle will mean a lot to
-me.  The more people I know are using this program, the more easily I can
-justify spending time on improvements and on the three-dimensional
-successor to Triangle, which in turn will benefit you.  Also, I can put
-you on a list to receive email whenever a new version of Triangle is
-available.
-
-If you use a mesh generated by Triangle or plotted by Show Me in a
-publication, please include an acknowledgment as well.
-
-
-Jonathan Richard Shewchuk
-July 20, 1996

Triangle/triangle.h

@@ -4,16 +4,14 @@
 /*                                                                           */
 /*  Include file for programs that call Triangle.                            */
 /*                                                                           */
-/*  Accompanies Triangle Version 1.3                                         */
+/*  Accompanies Triangle Versions 1.3 and 1.4                                */
 /*  July 19, 1996                                                            */
 /*                                                                           */
 /*  Copyright 1996                                                           */
 /*  Jonathan Richard Shewchuk                                                */
-/*  School of Computer Science                                               */
-/*  Carnegie Mellon University                                               */
-/*  5000 Forbes Avenue                                                       */
-/*  Pittsburgh, Pennsylvania  15213-3891                                     */
-/*  jrs@cs.cmu.edu                                                           */
+/*  2360 Woolsey #H                                                          */
+/*  Berkeley, California  94705-1927                                         */
+/*  jrs@cs.berkeley.edu                                                      */
 /*                                                                           */
 /*****************************************************************************/