Work-in-progress: new initial 2D meshing algorithm; new quasi-structured quad
algorithm; mesh renumbering now also renumbers dependent post-processing views;
mesh size callback is now per-model; OCC STL representation is now generated
using relative deflection tolerance; official binary builds now support OpenMP
parallelization and are 64 bit only (build OS upgraded to Windows 10, macOS
10.15 and Linux glibc 2.24); small bug fixes.

* Incompatible API changes: new arguments to mesh/getNode and mesh/getElement;
  new optional arguments to model/isInside, mesh/partition and
  occ/addSurfaceFilling; modified arguments to mesh/getKeysForElements,
  mesh/getKeysForElement and mesh/getInformationForElements; removed
  mesh/getLocalMultipliersForHcurl0.

4.8.4 (April 28, 2021): set current model in gmsh/model/add; small bug fixes.

4.8.3 (April 6, 2021): better handling of errors in inverse surface mapping;
fixed Mesh.MedFileMinorVersion for MED 4; small bug fixes.

4.8.2 (March 27, 2021): fixed regression in OCC transforms; fixed cwrap API.

4.8.1 (March 21, 2021): improved performance when transforming many OCC
entities; fixed regression in high-order meshing of surfaces with singular
parametrizations; small bug fixes.

4.8.0 (March 2, 2021): new interactive and fully parametrizable definition of
boundary conditions, materials, etc. through ONELAB variables; new API functions
for creating trimmed BSpline/Bezier patches, perform raw triangulations and
tetrehedralizations, get upward adjacencies, and create extruded boundary layers
and automatic curve loops in built-in kernel; improved performance of high-order
meshing of OCC models; improved handling of high resolution displays; new
structured CGNS exporter; new transfinite Beta law; added support for embedded
curves in HXT; added automatic conversion from partitioned MSH2 files to new
partitioned entities; element groups can now be imported from UNV files; fixed
order of Gauss quadrature for quads and hexas; code modernization (C++11);
further uniformization of option names to match the documented terminology
(Mesh.Point -> Mesh.Node, ...; old names are still accepted, but deprecated);
deprecated Mesh.MinimumElementsPerTwoPi: set value directly to
Mesh.MeshSizeFromCurvature instead; Python and Julia APIs now also define "snake
case" aliases for all camelCase function names; small bug fixes and
improvements.

* Incompatible API changes: new optional arguments to mesh/classifySurfaces,
  occ/addBSplineSurface, occ/addBezierSurface, occ/addPipe and view/probe;
  renamed mesh/getEdgeNumber as mesh/getEdges.

4.7.1 (November 16, 2020): small bug fixes and improvements.

4.7.0 (November 5, 2020): API errors now throw exceptions with the last error
message (instead of an integer error code); API functions now print messages on
the terminal by default, and throw exceptions on all errors unless in
interactive mode; new API functions to retrieve "homogeneous" model-based data
(for improved Python performance), to set interpolation matrices for high-order
datasets, to assign "automatic" transfinite meshing constraints and to pass
native (C++, C, Python or Julia) mesh size callback; added option to save
high-order periodic nodes info; added support for scripted window splitting;
improved VTK reader; new MatrixOfInertia command; added support for Unicode
command line arguments on Windows; uniformized commands, options and field
option names to match the documented terminology (CharacteristicLength ->
MeshSize, geometry Line -> Curve, ...; old names are still accepted, but
deprecated); improved handling of complex periodic cases; removed bundled Mmg3D
and added support for stock Mmg 5; Gmsh now requires C++11 and CMake 3.1, and
uses Eigen by default instead of Blas/Lapack for dense linear algebra; small bug
fixes.

* Incompatible API changes: new optional argument to geo/addCurveLoop.

4.6.0 (June 22, 2020): new options to only generate initial 2D or 3D meshes
(without node insertion), and to only mesh non-meshed entities; added ability to
only remesh parts of discrete models; added support for mesh size fields and
embedded points and surfaces in HXT; improved reparametrization and partitioning
code; new OCC API functions to reduce the number of synchronizations for complex
models; new OCC spline surface interfaces; new functions and options to control
the first tag of entities, nodes and elements; fixed duplicated entities in STEP
output; improved mesh subdivision and high-order pipeline; MED output now
preserves node and element tags; small bug fixes.

* Incompatible API changes: new optional arguments to mesh/clear,
  mesh/createTopology, mesh/createGeometry, occ/addThruSections,
  mesh/getPeriodicNodes; new arguments to mesh/getBasisFunctions; removed
  mesh/preallocateBasisFunctions, mesh/precomputeBasisFunctions and
  mesh/getBasisFunctionsForElements; renamed occ/setMeshSize as
  occ/mesh/setSize.

4.5.6 (March 30, 2020): better calculation of OCC bounding boxes using STL; API
tutorials; small bug fixes.

4.5.5 (March 21, 2020): tooltips in GUI to help discovery of scripting options;
fixed MED IO of high-order elements; fixed OCC attribute search by bounding box;
fix parsing of mac-encoded scripts; new RecombineMesh command; added support for
extrusion of mixed-dimension entities with OCC; small bug fixes.

4.5.4 (February 29, 2020): periodic mesh optimization now ensures that the
master mesh is not modified; code cleanup; small bug fixes.

4.5.3 (February 22, 2020): improved positioning of corresponding nodes on
periodic entities; improved LaTeX output; improved curve splitting in
reparametrization; new binary PLY reader; small compilation fixes.

4.5.2 (January 30, 2020): periodic meshes now obey reorientation constraints;
physical group definitions now follow compound meshing constraints; small bug
fixes and improvements.

4.5.1 (December 28, 2019): new Min and Max commands in .geo files;
Mesh.MinimumCirclePoints now behaves the same with all geometry kernels; fixed
issue with UTF16-encoded home directories on Windows.

4.5.0 (December 21, 2019): changed default 2D meshing algorithm to
Frontal-Delaunay; new compound Spline/BSpline commands; new MeshSizeFromBoundary
command; new CGNS importer/exporter; new X3D exporter for geometries and meshes;
improved surface mesh reclassification; new separate option to govern curvature
adapted meshes (Mesh.MinimumElementsPerTwoPi and "-clcurv val"); improved
handling of anisotropic surface meshes in 3D Delaunay; improved high-order
periodic meshing; improved 2D boolean unions; file chooser type is now
changeable at runtime; FLTK GUI can now be created and destroyed at will through
the API; fixed regression in MeshAdapt for non-periodic surfaces with
singularities; combining views now copies options; added API support for mesh
compounds, per-surface mesh algorithm and mesh size from boundary; renamed
plugin AnalyseCurvedMesh to AnalyseMeshQuality; fixed regression for built-in
kernel BSplines on non-flat geometries (Sphere, PolarSphere); small fixes and
improvements.

* Incompatible API changes: removed mesh/smooth (now handled by mesh/optimize
  like all other mesh optimizers); renamed logger/time to logger/getWallTime and
  logger/cputime to logger/getCpuTime; new arguments to mesh/optimize,
  mesh/getElementProperties and occ/healShapes; added optional argument to
  mesh/classifySurfaces and view/combine.

4.4.1 (July 25, 2019): small improvements (transfinite with degenerate curves,
renumbering for some mesh formats, empty MSH file sections, tunable accuracy of
compound meshes) and bug fixes (ellipse < pi, orientation and reclassification
of compound parts, serendip pyramids, periodic MeshAdapt robustness, invalidate
cache after mesh/addNodes).

4.4.0 (July 1, 2019): new STL remeshing workflow (with new ClassifySurfaces
command in .geo files); added API support for color options, mesh optimization,
recombination, smoothing and shape healing; exposed additional METIS options;
improved support for periodic entities (multiple curves with the same start/end
points, legacy MSH2 format, periodic surfaces with embedded entities); added
mesh renumbering also after interactive mesh modifications; improved support for
OpenCASCADE ellipse arcs; new interactive filter in visibility window; flatter
GUI; small bug fixes.

* Incompatible API changes: mesh/getJacobians and mesh/getBasisFunctions now
  take integration points explicitly; mesh/setNodes and mesh/setElements have
  been replaced by mesh/addNodes and mesh/addElements; added optional arguments
  to mesh/classifySurfaces and occ/addSurfaceLoop; changed arguments of
  occ/addEllipseArc to follow geo/addEllipseArc.

4.3.0 (April 19, 2019): improved meshing of surfaces with singular
parametrizations; added API support for aliasing and combining views, copying
view options, setting point coordinates, extruding built-in CAD entities along
normals and retrieving mass, center of mass and inertia from OpenCASCADE CAD
entities; fixed regression introduced in 4.1.4 that could lead to
non-deterministic 2D meshes; small bug fixes.

* Incompatible API changes: added optional arguments to mesh/getNodes and
  mesh/getElementByCoordinates.

4.2.3 (April 3, 2019): added STL export by physical surface; added ability to
remove embedded entities; added handling of boundary entities in
addDiscreteEntity; small bug fixes.

4.2.2 (March 13, 2019): fixed regression in reading of extruded meshes; added
ability to export one solid per surface in STL format.

4.2.1 (March 7, 2019): fixed regression for STEP files without global compound
shape; added support for reading IGES labels and colors; improved search for
shared library in Python and Julia modules; improved Plugin(MeshVolume); updates
to the reference manual.

4.2.0 (March 5, 2019): new MSH4.1 revision of the MSH file format, with support
for size_t node and element tags (see the reference manual for detailed
changes); added support for reading STEP labels and colors with OCC CAF; changed
default "Geometry.OCCTargetUnit" value to none (i.e. use STEP file coordinates
as-is, without conversion); improved high-order mesh optimization; added ability
to import groups of nodes from MED files; enhanced Plugin(Distance) and
Plugin(SimplePartition); removed unmaintained plugins; removed default
dependency on PETSc; small improvements and bug fixes.

* Incompatible API changes: changed type of node and element tags from int to
  size_t to support (very) large meshes; changed logger/start,
  mesh/getPeriodicNodes and mesh/setElementsByType.

4.1.5 (February 14, 2019): improved OpenMP parallelization, STL remeshing, mesh
partitioning and high-order mesh optimization; added classifySurfaces in API;
bug fixes.

4.1.4 (February 3, 2019): improved ghost cell I/O; added getGhostElements,
relocateNodes, getElementType, getElementFaceNodes, getElementEdgeNodes
functions in API; small improvements and bug fixes.

4.1.3 (January 23, 2019): improved quad meshing; new options for automatic
full-quad meshes; save nodesets also for physical points (Abaqus, Tochnog); new
getPartitions, unpartition and removePhysicalName functions in API; small bug
fixes.

4.1.2 (January 21, 2019): fixed full-quad subdivision if Mesh.SecondOrderLinear
is set; fixed packing of parallelograms regression in 4.1.1.

4.1.1 (January 20, 2019): added support for general affine transformations with
OpenCASCADE kernel; improved handling of boolean tolerance (snap vertices);
faster crossfield calculation by default (e.g. for Frontal-Delauany for quads
algorithm); fixed face vertices for PyramidN; renamed ONELAB "Action" and
"Button" parameters "ONELAB/Action" and "ONELAB/Button"; added support for
actions on any ONELAB button; added API functions for selections in user
interface.

4.1.0 (January 13, 2019): improved ONELAB and Fltk support in API; improved
renumbering of mesh nodes/elements; major code refactoring.

* Incompatible API changes: changed onelab/get.

4.0.7 (December 9, 2018): fixed small memory leaks; removed unused code.

4.0.6 (November 25, 2018): moved private API wrappers to utils/wrappers;
improved Gmsh 3 compatibility for high-order periodic meshes; fixed '-v 0' not
being completely silent; fixed rendering of image textures on some OSes; small
compilation fixes.

4.0.5 (November 17, 2018): new automatic hybrid mesh generation (pyramid layer)
when 3D Delaunay algorithm is applied to a volume with quadrangles on boundary;
improved robustness of 2D MeshAdapt algorithm; bug fixes.

4.0.4 (October 19, 2018): fixed physical names regression in 4.0.3.

4.0.3 (October 18, 2018): bug fixes.

4.0.2 (September 26, 2018): added support for creating MED files with specific
MED (minor) version; small bug fixes.

4.0.1 (September 7, 2018): renumber mesh nodes/elements by default; new
SendToServer command for nodal views; added color and visibility handling in
API; small bug fixes.

4.0.0 (August 22, 2018): new C++, C, Python and Julia API; new MSH4 format; new
mesh partitioning code based on Metis 5; new 3D tetrahedralization algorithm as
default; new workflow for remeshing (compound entities as meshing constraints,
CreateGeometry for mesh reparametrization); added support for general BSplines,
fillets and chamfers with OpenCASCADE kernel and changed default BSpline
parameters with the built-in kernel to match OpenCASCADE's; STEP files are now
be default interpreted in MKS units (see Geometry.OCCTargetUnit); improved
meshing of surfaces with singular parametrizations (spheres, etc.); uniformized
entity naming conventions (line/curve, vertex/node, etc.); generalized handling
of "all" entities in geo file (using {:} notation); added support for creating
LSDYNA mesh files; removed old CAD creation factory (GModelFactory), old
reparametrization code (G{Edge, Face, Region}Compound) and old partitioning
code (Metis 4 and Chaco); various cleanups, bug fixes and enhancements.

3.0.6 (November 5, 2017): improved meshing of spheres; improved handling of mesh
size constraints with OpenCASCADE kernel; implemented "Coherence" for
OpenCASCADE kernel (shortcut for BooleanFragments); added GAMBIT Neutral File
export; small improvements and bug fixes.

3.0.5 (September 6, 2017): bug fixes.

3.0.4 (July 28, 2017): moved vorometal code to plugin; OpenMP improvements; bug
fixes.

3.0.3 (June 27, 2017): new element quality measures; Block->Box; minor fixes.

3.0.2 (May 13, 2017): improved handling of meshing constraints and entity
numbering after boolean operations; improved handling of fast coarseness
transitions in MeshAdapt; new TIKZ export; small bug fixes.

3.0.1 (April 14, 2017): fixed OpenCASCADE plane surfaces with holes.

3.0.0 (April 13, 2017): new constructive solid geometry features and boolean
operations using OpenCASCADE; improved graphical user interface for interactive,
parametric geometry construction; new or modified commands in .geo files:
SetFactory, Circle, Ellipse, Wire, Surface, Sphere, Block, Torus, Rectangle,
Disk, Cylinder, Cone, Wedge, ThickSolid, ThruSections, Ruled ThruSections,
Fillet, Extrude, BooleanUnion, BooleanIntersection, BooleanDifference,
BooleanFragments, ShapeFromFile, Recursive Delete, Unique; "Surface" replaces
the deprecated "Ruled Surface" command; faster 3D tetrahedral mesh optimization
enabled by default; major code refactoring and numerous bug fixes.

2.16.0 (January 3, 2017): small improvements (list functions, second order hexes
for MED, GUI) and bug fixes.

2.15.0 (December 4, 2016): fixed several regressions (multi-file partitioned
grid export, mesh subdivision, old compound mesher); improved 2D boundary layer
field & removed non-functional 3D boundary layer field; faster rendering of
large meshes.

2.14.1 (October 30, 2016): fixed regression in periodic meshes; small bug fixes
and code cleanups.

2.14.0 (October 9, 2016): new Tochnog file format export; added ability to
remove last command in scripts generated interactively; ONELAB 1.3 with
usability and performance improvements; faster "Coherence Mesh".

2.13.2 (August 18, 2016)): small improvements (scale labels, periodic and
high-order meshes) and bug fixes.

2.13.1 (July 15, 2016): small bug fixes.

2.13.0 (July 11, 2016): new ONELAB 1.2 protocol with native support for lists;
new experimental 3D boundary recovery code and 3D refinement algorithm; better
adaptive visualization of quads and hexahedra; fixed several regressions
introduced in 2.12.

2.12.0 (March 5, 2016): improved interactive definition of physical groups and
handling of ONELAB clients; improved full quad algorithm; added support for list
of strings, trihedra elements and X3D format; improved message console; new
colormaps; various bugs fixes and small improvements all over.

2.11.0 (November 7, 2015): new Else/ElseIf commands; new OptimizeMesh command;
Plugin(ModifyComponents) replaces Plugin(ModifyComponent); new VTK and X3D
outputs; separate 0/Ctrl+0 shortcuts for geometry/full model reload; small bug
fixes in homology solver, handling of embedded entities, and Plugin(Crack).

2.10.1 (July 30, 2015): minor fixes.

2.10.0 (July 21, 2015): improved periodic meshing constraints; new Physical
specification with both label and numeric id; images can now be used as glyphs
in post-processing views, using text annotations with the `file://' prefix;
Views can be grouped and organized in subtrees; improved visibility browser
navigation; geometrical entities and post-processing views can now react to
double-clicks, via new generic DoubleClicked options; new Get/SetNumber and
Get/SetString for direct access to ONELAB variables; small bug fixes and code
cleanups.

2.9.3 (April 18, 2015): updated versions of PETSc/SLEPc and OpenCASCADE/OCE
libraries used in official binary builds; new Find() command; miscellaneous code
cleanups and small fixes.

2.9.2 (March 31, 2015): added support for extrusion of embedded points/curves;
improved hex-dominant algorithm; fixed crashes in quad algorithm; fix regression
in MED reader introduced in 2.9.0; new dark interface mode.

2.9.1 (March 18, 2015): minor bug fixes.

2.9.0 (March 12, 2015): improved robustness of spatial searches (extruded meshes,
geometry coherence); improved reproductibility of 2D and 3D meshes; added
support for high resolution ("retina") graphics; interactive graph point
commands; on-the-fly creation of onelab clients in scripts; general periodic
meshes using afine transforms; scripted selection of entities in bounding boxes;
extended string and list handling functions; many small improvements and bug
fixes.

2.8.5 (Jul 9, 2014): improved stability and error handling, better Coherence
function, updated onelab API version and inline parameter definitions, new
background image modes, more robust Triangulate/Tetrahedralize plugins, new PGF
output, improved support for string~index variable names in parser, small
improvements and bug fixes all over the place.

2.8.4 (Feb 7, 2014): better reproductibility of 2D meshes; new mandatory 'Name'
attribute to define onelab variables in DefineConstant[] & co; new
-setnumber/-setstring command line arguments; small improvements and bug fixes.

2.8.3 (Sep 27, 2013): new quick access menu and multiple view selection in GUI;
enhanced animation creation; many small enhancements and bug fixes.

2.8.2 (Jul 16, 2013): improved high order tools interface; minor bug fixes.

2.8.1 (Jul 11, 2013): improved compound surfaces and transfinite arrangements.

2.8.0 (Jul 8, 2013): improved Delaunay point insertion; fixed mesh orientation
of plane surfaces; fixed mesh size prescribed at embedded points; improved
display of vectors at COG; new experimental text string display engines;
improved fullscreen mode; access time/step in transformations; new experimental
features: AdaptMesh and Surface In Volume; accept unicode file paths on Windows;
compilation and bug fixes.

2.7.1 (May 11, 2013): improved Delaunay point insertion; updated onelab; better
Abaqus and UNV export; small bug and compilation fixes.

2.7.0 (Mar 9, 2013): new single-window GUI, with dynamically customizable
widget tree; faster STEP/BRep import; arbitrary size image export; faster 2D
Delaunay/Frontal algorithms; full option viewer/editor; many bug fixes.

2.6.1 (Jul 15, 2012): minor improvements and bug fixes.

2.6.0 (Jun 19, 2012): new quadrilateral meshing algorithms (Blossom and
Delaunay-Frontal for quads); new solver module based on ONELAB project (requires
FLTK 1.3); new tensor field visualization modes (eigenvectors, ellipsoid, etc.);
added support for interpolation schemes in .msh file; added support for MED3
format; rescale viewport around visible entities (shift+1:1 in GUI); unified
post-processing field export; new experimental stereo+camera visualization mode;
added experimental BAMG & Mmg3D support for anisotropic mesh generation; new OCC
cut & merge algorithm imported from Salome; new ability to connect extruded
meshes to tetrahedral grids using pyramids; new homology solver; Abaqus (INP)
mesh export; new Python and Java wrappers; bug fixes and small improvements all
over the place.

2.5.0 (Oct 15, 2010): new compound geometrical entities (for remeshing and/or
trans-patch meshing); improved mesh reclassification tool; new client/server
visualization mode; new ability to watch a pattern of files to merge; new
integrated MPEG export; new option to force the type of views dynamically;
bumped mesh version format to 2.2 (small change in the meaning of the partition
tags; this only affects partitioned (i.e. parallel) meshes); renamed several
post-processing plugins (as well as plugin options) to make them easier to
understand; many bug fixes and usability improvements all over the place.

2.4.2 (Sep 21, 2009): solver code refactoring + better IDE integration.

2.4.1 (Sep 1, 2009): fixed surface mesh orientation bug introduced in 2.4.0;
mesh and graphics code refactoring, small usability enhancements and bug fixes.

2.4.0 (Aug 22, 2009): switched build system to CMake; optionally copy
transfinite mesh constraints during geometry transformations; bumped mesh
version format to 2.1 (small change in the $PhysicalNames section, where the
group dimension is now required); ported most plugins to the new
post-processing API; switched from MathEval to MathEx and Flu_Tree_Browser to
Fl_Tree; small bug fixes and improvements all over the place.

2.3.1 (Mar 18, 2009): removed GSL dependency (Gmsh now simply uses Blas and
Lapack); new per-window visibility; added support for composite window printing
and background images; fixed string option affectation in parser; fixed surface
mesh orientation for OpenCASCADE models; fixed random triangle orientations in
Delaunay and Frontal algorithms.

2.3.0 (Jan 23, 2009): major graphics and GUI code refactoring; new
full-quad/hexa subdivision algorithm; improved automatic transfinite corner
selection (now also for volumes); improved visibility browser; new automatic
adaptive visualization for high-order simplices; modified arrow size, clipping
planes and transform options; many improvements and bug fixes all over the
place.

2.2.6 (Nov 21, 2008): better transfinite smoothing and automatic corner
selection; fixed high order meshing crashes on Windows and Linux; new uniform
mesh refinement (thanks Brian!); fixed various other small bugs.

2.2.5 (Oct 25, 2008): Gmsh now requires FLTK 1.1.7 or above; various small
improvements (STL and VTK mesh I/O, Netgen upgrade, Visual C++ support, Fields,
Mesh.{Msh,Stl,...}Binary changed to Mesh.Binary) and bug fixes (pyramid
interpolation, Chaco crashes).

2.2.4 (Aug 14, 2008): integrated Metis and Chaco mesh partitioners; variables
can now be deleted in geo files; added support for point datasets in model-based
postprocessing views; small bug fixes.

2.2.3 (Jul 14, 2008): enhanced clipping interface; API cleanup; fixed various
bugs (Plugin(Integrate), high order meshes, surface info crash).

2.2.2 (Jun 20, 2008): added geometrical transformations on volumes; fixed bug in
high order mesh generation.

2.2.1 (Jun 15, 2008): various small improvements (adaptive views, GUI, code
cleanup) and bug fixes (high order meshes, Netgen interface).

2.2.0 (Apr 19, 2008): new model-based post-processing backend; added MED I/O for
mesh and post-processing; fixed BDF vertex ordering for 2nd order elements;
replaced Mesh.ConstrainedBackgroundMesh with
Mesh.CharacteristicLength{FromPoints,ExtendFromBoundary}; new Fields interface;
control windows are now non-modal by default; new experimental 2D frontal
algorithm; fixed various bugs.

2.1.1 (Mar 1, 2008): small bug fixes (second order meshes, combine views, divide
and conquer crash, ...).

2.1.0 (Feb 23, 2008): new post-processing database; complete rewrite of
post-processing drawing code; improved surface mesh algorithms; improved
STEP/IGES/BREP support; new 3D mesh optimization algorithm; new default native
file choosers; fixed 'could not find extruded vertex' in extrusions; many
improvements and bug fixes all over the place.

2.0.8 (Jul 13, 2007): unused vertices are not saved in mesh files anymore; new
plugin GUI; automatic GUI font size selection; renamed
Plugin(DecomposeInSimplex) into Plugin(MakeSimplex); reintroduced enhanced
Plugin(SphericalRaise); clarified meshing algo names; new option to save groups
of nodes in UNV meshes; new background mesh infrastructure; many small
improvements and small bug fixes.

2.0.7 (Apr 3, 2007): volumes can now be defined from external CAD surfaces;
Delaunay/Tetgen algorithm is now used by default when available; re-added
support for Plot3D structured mesh format; added ability to export external CAD
models as GEO files (this only works for the limited set of geometrical
primitives available in the GEO language, of course--so trying to convert e.g. a
trimmed NURBS from a STEP file into a GEO file will fail); "lateral" entities
are now added at the end of the list returned by extrusion commands; fixed
various bugs.

2.0.0 (Feb 5, 2007): new geometry and mesh databases, with support for STEP and
IGES import via OpenCASCADE; complete rewrite of geometry and mesh drawing
code; complete rewrite of mesh I/O layer (with new native binary MSH format and
support for import/export of I-deas UNV, Nastran BDF, STL, Medit MESH and VRML
1.0 files); added support for incomplete second order elements; new 2D and 3D
meshing algorithms; improved integration of Netgen and TetGen algorithms;
removed anisotropic meshing algorithm (as well as attractors); removed explicit
region number specification in extrusions; option changes in the graphical
interface are now applied instantaneously; added support for offscreen rendering
using OSMesa; added support for SVG output; added string labels for Physical
entities; lots of other improvements all over the place.

1.65 (May 15, 2006): new Plugin(ExtractEdges); fixed compilation errors with
gcc4.1; replaced Plugin(DisplacementRaise) and Plugin(SphericalRaise) with the
more flexible Plugin(Warp); better handling of discrete curves; new Status
command in parser; added option to renumber nodes in .msh files (to avoid holes
in the numbering sequence); fixed 2 special cases in quad->prism extrusion;
fixed saving of 2nd order hexas with negative volume; small bug fixes and
cleanups.

1.64 (Mar 18, 2006): Windows versions do no depend on Cygwin anymore; various
bug fixes and cleanups.

1.63 (Feb 01, 2006): post-processing views can now be exported as meshes;
improved background mesh handling (a lot faster, and more accurate); improved
support for input images; new Plugin(ExtractElements); small bug fixes and
enhancements.

1.62 (Jan 15, 2006): new option to draw color gradients in the background;
enhanced perspective projection mode; new "lasso" selection mode (same as
"lasso" zoom, but in selection mode); new "invert selection" button in the
visibility browser; new snapping grid when adding points in the GUI; nicer
normal smoothing; new extrude syntax (old syntax still available, but
deprecated); various small bug fixes and enhancements.

1.61 (Nov 29, 2005): added support for second order (curved) elements in
post-processor; new version (1.4) of post-processing file formats; new stippling
options for 2D plots; removed limit on allowed number of files on command line;
all "Combine" operations are now available in the parser; changed
View.ArrowLocation into View.GlyphLocation; optimized memory usage when loading
many (>1000) views; optimized loading and drawing of line meshes and 2D iso
views; optimized handling of meshes with large number of physical entities;
optimized vertex array creation for large post-processing views on
Windows/Cygwin; removed Discrete Line and Discrete Surface commands (the same
functionality can now be obtained by simply loading a mesh in .msh format);
fixed coloring by mesh partition; added option to light wireframe meshes and
views; new "mesh statistics" export format; new full-quad recombine option; new
Plugin(ModulusPhase); hexas and prisms are now always saved with positive
volume; improved interactive entity selection; new experimental Tetgen
integration; new experimental STL remeshing algorithm; various small bug fixes
and improvements.

1.60 (Mar 15, 2005): added support for discrete curves; new Window menu on Mac
OS X; generalized all octree-based plugins (CutGrid, StreamLines, Probe, etc.)
to handle all element types (and not only scalar and vector
triangles+tetrahedra); generalized Plugin(Evaluate), Plugin(Extract) and
Plugin(Annotate); enhanced clipping plane interface; new grid/axes/rulers for 3D
post-processing views (renamed the AbscissaName, NbAbscissa and AbscissaFormat
options to more general names in the process); better automatic positioning of
2D graphs; new manipulator dialog to specify rotations, translations and
scalings "by hand"; various small enhancements and bug fixes.

1.59 (Feb 06, 2005): added support for discrete (triangulated) surfaces, either
in STL format or with the new "Discrete Surface" command; added STL and Text
output format for post-processing views and STL output format for surface
meshes; all levelset-based plugins can now also compute isovolumes; generalized
Plugin(Evaluate) to handle external view data (based on the same or on a
different mesh); generalized Plugin(CutGrid); new plugins (Eigenvalues,
Gradient, Curl, Divergence); changed default colormap to match Matlab's "Jet"
colormap; new transformation matrix option for views (for non-destructive
rotations, symmetries, etc.); improved solver interface to keep the GUI
responsive during solver calls; new C++ and Python solver examples; simplified
Tools->Visibility GUI; transfinite lines with "Progression" now allow negative
line numbers to reverse the progression; added ability to retrieve Gmsh's
version number in the parser (to help write backward compatible scripts); fixed
white space in unv mesh output; fixed various small bugs.

1.58 (Jan 01, 2005): fixed UNIX socket interface on Windows (broken by the TCP
solver patch in 1.57); bumped version number of default post-processing file
formats to 1.3 (the only small modification is the handling of the end-of-string
character for text2d and text3d objects in the ASCII format); new File->Rename
menu; new colormaps+improved colormap handling; new color+min/max options in
views; new GetValue() function to ask for values interactively in scripts;
generalized For/EndFor loops in parser; new plugins (Annotate, Remove, Probe);
new text attributes in views; renamed some shortcuts; fixed TeX output for large
scenes; new option dialogs for various output formats; fixed many small memory
leaks in parser; many small enhancements to polish the graphics and the user
interface.

1.57 (Dec 23, 2004): generalized displacement maps to display arbitrary view
types; the arrows representing a vector field can now also be colored by the
values from other scalar, vector or tensor fields; new adaptive high order
visualization mode; new options (Solver.SocketCommand, Solver.NameCommand,
View.ArrowSizeProportional, View.Normals, View.Tangents and General.ClipFactor);
fixed display of undesired solver plugin popups; enhanced interactive plugin
behavior; new plugins (HarmonicToTime, Integrate, Eigenvectors); tetrahedral
mesh file reading speedup (50% faster on large meshes); large memory footprint
reduction (up to 50%) for the visualization of triangular/tetrahedral meshes;
the solver interface now supports TCP/IP connections; new generalized raise mode
(allows one to use complex expressions to offset post-processing maps); upgraded
Netgen kernel to version 4.4; new optional TIME list in parsed views to specify
the values of the time steps; several bug fixes in the Elliptic mesh algorithm;
various other small bug fixes and enhancements.

1.56 (Oct 17, 2004): new post-processing option to draw a scalar view raised by
a displacement view without using Plugin(DisplacementRaise) (makes drawing
arbitrary scalar fields on deformed meshes much easier); better post-processing
menu (arbitrary number of views+scrollable+show view number); improved
view->combine; new horizontal post-processing scales; new option to draw the
mesh nodes per element; views can now also be saved in "parsed" format; fixed
various path problems on Windows; small bug fixes.

1.55 (Aug 21, 2004): added background mesh support for Triangle; meshes can now
be displayed using "smoothed" normals (like post-processing views); added GUI
for clipping planes; new interactive clipping/cutting plane definition;
reorganized the Options GUI; enhanced 3D iso computation; enhanced lighting;
many small bug fixes.

1.54 (Jul 03, 2004): integrated Netgen (3D mesh quality optimization +
alternative 3D algorithm); Extrude Surface now always automatically creates a
new volume (in the same way Extrude Point or Extrude Line create new lines and
surfaces, respectively); fixed UNV output; made the "Layers" region numbering
consistent between lines, surfaces and volumes; fixed home directory problem on
Win98; new Plugin(CutParametric); the default project file is now created in the
home directory if no current directory is defined (e.g., when double-clicking on
the icon on Windows/Mac); fixed the discrepancy between the orientation of
geometrical surfaces and the associated surface meshes; added automatic
orientation of surfaces in surface loops; generalized Plugin(Triangulate) to
handle vector and tensor views; much nicer display of discrete iso-surfaces and
custom ranges using smooth normals; small bug fixes and cleanups.

1.53 (Jun 04, 2004): completed support for second order elements in the mesh
module (line, triangles, quadrangles, tetrahedra, hexahedra, prisms and
pyramids); various background mesh fixes and enhancements; major performance
improvements in mesh and post-processing drawing routines (OpenGL vertex arrays
for tri/quads); new Plugin(Evaluate) to evaluate arbitrary expressions on
post-processing views; generalized Plugin(Extract) to handle any combination of
components; generalized "Coherence" to handle transfinite surface/volume
attributes; plugin options can now be set in the option file (like all other
options); added "undo" capability during geometry creation; rewrote the contour
guessing routines so that entities can be selected in an arbitrary order; Mac
users can now double click on geo/msh/pos files in the Finder to launch Gmsh;
removed support for FLTK 1.0; rewrote most of the code related to quadrangles;
fixed 2d elliptic algorithm; removed all OpenGL display list code and options;
fixed light positioning; new BoundingBox command to set the bounding box
explicitly; added support for inexpensive "fake" transparency mode; many code
cleanups.

1.52 (May 06, 2004): new raster ("bitmap") PostScript/EPS/PDF output formats;
new Plugin(Extract) to extract a given component from a post-processing view;
new Plugin(CutGrid) and Plugin(StreamLines); improved mesh projection on
non-planar surfaces; added support for second order tetrahedral elements; added
interactive control of element order; refined mesh entity drawing selection (and
renamed most of the corresponding options); enhanced log scale in
post-processing; better font selection; simplified View.Raise{X,Y,Z} by removing
the scaling; various bug fixes (default postscript printing mode, drawing of 3D
arrows/cylinders on Linux, default home directory on Windows, default initial
file browser directory, extrusion of points with non-normalized axes of
rotation, computation of the scene bounding box in scripts, + the usual
documentation updates).

1.51 (Feb 29, 2004): initial support for visualizing mesh partitions; integrated
version 2.0 of the MSH mesh file format; new option to compute post-processing
ranges (min/max) per time step; Multiple views can now be combined into multi
time step ones (e.g. for programs that generate data one time step at a time);
new syntax: #var[] returns the size of the list var[]; enhanced "gmsh -convert";
temporary and error files are now created in the home directory to avoid file
permission issues; new 3D arrows; better lighting support; STL facets can now be
converted into individual geometrical surfaces; many other small improvements
and bug fixes (multi timestep tensors, color by physical entity, parser cleanup,
etc.).

1.50 (Dec 06, 2003): small changes to the visibility browser + made visibility
scriptable (new Show/Hide commands); fixed (rare) crash when deleting views;
split File->Open into File->Open and File->New to behave like most other
programs; Mac versions now use the system menu bar by default (if possible);
fixed bug leading to degenerate and/or duplicate tetrahedra in extruded meshes;
fixed crash when reloading sms meshes.

1.49 (Nov 30, 2003): made Merge, Save and Print behave like Include (i.e., open
files in the same directory as the main project file if the path is relative);
new Plugin(DecomposeInSimplex); new option View.AlphaChannel to set the
transparency factor globally for a post-processing view; new "Combine Views"
command; various bug fixes and cleanups.

1.48 (Nov 23, 2003): new DisplacementRaise plugin to plot arbitrary fields on
deformed meshes; generalized CutMap, CutPlane, CutSphere and Skin plugins to
handle all kinds of elements and fields; new "Save View[n]" command to save
views from a script; many small bug fixes (configure tests for libpng, handling
of erroneous options, multi time step scalar prism drawings, copy of surface
mesh attributes, etc.).

1.47 (Nov 12, 2003): fixed extrusion of surfaces defined by only two curves; new
syntax to retrieve point coordinates and indices of entities created through
geometrical transformations; new PDF and compressed PostScript output formats;
fixed numbering of elements created with "Extrude Point/Line"; use $GMSH_HOME as
home directory if defined.

1.46 (Aug 23, 2003): fixed crash for very long command lines; new options for
setting the displacement factor and Triangle's parameters + renamed a couple of
options to more sensible names (View.VectorType, View.ArrowSize); various small
bug fixes; documentation update.

1.45 (Jun 14, 2003): small bug fixes (min/max computation for tensor views,
missing physical points in read mesh, "jumping" geometry during interactive
manipulation of large models, etc.); variable definition speedup; restored
support for second order elements in one- and two-dimensional meshes;
documentation updates.

1.44 (Apr 21, 2003): new reference manual; added support for PNG output; fixed
small configure script bugs.

1.43 (Mar 28, 2003): fixed solver interface problem on Mac OS X; new option to
specify the interactive rotation center (default is now the pseudo "center of
gravity" of the object, instead of (0,0,0)).

1.42 (Mar 19, 2003): suppressed the automatic addition of a ".geo" extension if
the file given on the command line is not recognized; added missing Layer option
for Extrude Point; fixed various small bugs.

1.41 (Mar 04, 2003): Gmsh is now licensed under the GNU General Public License;
general code cleanup (indent).

1.40 (Feb 26, 2003): various small bug fixes (mainly GSL-related).

1.39 (Feb 23, 2003): removed all non-free routines; more build system work;
implemented Von-Mises tensor display for all element types; fixed small GUI
bugs.

1.38 (Feb 17, 2003): fixed custom range selection for 3D iso graphs; new build
system based on autoconf; new image reading code to import bitmaps as
post-processing views.

1.37 (Jan 25, 2003): generalized smoothing and cuts of post-processing views;
better Windows integration (solvers, external editors, etc.); small bug fixes.

1.36 (Nov 20, 2002): enhanced view duplication (one can now use "Duplicata
View[num]" in the input file); merged all option dialogs in a new general option
window; enhanced discoverability of the view option menus; new 3D point and line
display; many small bug fixes and enhancements ("Print" format in parser,
post-processing statistics, smooth normals, save window positions, restore
default options, etc.).

1.35 (Sep 11, 2002): graphical user interface upgraded to FLTK 1.1 (tooltips,
new file chooser with multiple selection, full keyboard navigation, cut/paste of
messages, etc.); colors can be now be directly assigned to mesh entities;
initial tensor visualization; new keyboard animation (right/left arrow for time
steps; up/down arrow for view cycling); new VRML output format for surface
meshes; new plugin for spherical elevation plots; new post-processing file
format (version 1.2) supporting quadrangles, hexahedra, prisms and pyramids;
transparency is now enabled by default for post-processing plots; many small bug
fixes (read mesh, ...).

1.34 (Feb 18, 2002): improved surface mesh of non-plane surfaces; fixed
orientation of elements in 2D anisotropic algorithm; minor user interface polish
and additions (mostly in post-processing options); various small bug fixes.

1.33 (Jan 24, 2002): new parameterizable solver interface (allowing up to 5
user-defined solvers); enhanced 2D aniso algorithm; 3D initial mesh speedup.

1.32 (Oct 04, 2001): new visibility browser; better floating point exception
checks; fixed infinite looping when merging meshes in project files; various
small clean ups (degenerate 2D extrusion, view->reload, ...).

1.31 (Nov 30, 2001): corrected ellipses; PostScript output update (better
shading, new combined PS/LaTeX output format); more interface polish; fixed
extra memory allocation in 2D meshes; Physical Volume handling in unv format;
various small fixes.

1.30 (Nov 16, 2001): interface polish; fix crash when extruding quadrangles.

1.29 (Nov 12, 2001): translations and rotations can now be combined in
extrusions; fixed coherence bug in Extrude Line; various small bug fixes and
additions.

1.28 (Oct 30, 2001): corrected the 'Using Progression' attribute for tranfinite
meshes to actually match a real geometric progression; new Triangulate plugin;
new 2D graphs (space+time charts); better performance of geometrical
transformations (warning: the numbering of some automatically created entities
has changed); new text primitives in post-processing views (file format updated
to version 1.1); more robust mean plane computation and error checks; various
other small additions and clean-ups.

1.27 (Oct 05, 2001): added ability to extrude curves with Layers/Recombine
attributes; new PointSize/LineWidth options; fixed For/EndFor loops in included
files; fixed error messages (line numbers+file names) in loops and functions;
made the automatic removal of duplicate geometrical entities optional
(Geometry.AutoCoherence=0); various other small bug fixes and clean-ups.

1.26 (Sep 06, 2001): enhanced 2D anisotropic mesh generator (metric
intersections); fixed small bug in 3D initial mesh; added alternative syntax for
built-in functions (for GetDP compatibility); added line element display; Gmsh
now saves all the elements in the mesh if no physical groups are defined (or if
Mesh.SaveAll=1).

1.25 (Sep 01, 2001): fixed bug with mixed recombined/non-recombined extruded
meshes; Linux versions are now build with no optimization, due to bugs in gcc
2.95.X.

1.24 (Aug 30, 2001): fixed characteristic length interpolation for Splines;
fixed edge swapping bug in 3D initial mesh; fixed degenerated case in
geometrical extrusion (ruled surface with 3 borders); fixed generation of
degenerated hexahedra and prisms for recombined+extruded meshes; added BSplines
creation in the GUI; integrated Jonathan Shewchuk's Triangle as an alternative
isotropic 2D mesh generator; added AngleSmoothNormals to control sharp edge
display with smoothed normals; fixed random crash for lighted 3D iso surfaces.

1.23 (Aug, 2001): fixed duplicate elements generation + non-matching tetrahedra
faces in 3D extruded meshes; better display of displacement maps; fixed
interactive ellipsis construction; generalized boundary operator; added new
explode option for post-processing views; enhanced link view behavior (to update
only the changed items); added new default plugins: Skin, Transform, Smooth;
fixed various other small bugs (mostly in the post-processing module and for
extruded meshes).

1.22 (Aug 03, 2001): fixed (yet another) bug for 2D mesh in the mean plane;
fixed surface coherence bug in extruded meshes; new double logarithmic scale,
saturate value and smoothed normals option for post-processing views; plugins
are now enabled by default; three new experimental statically linked plugins:
CutMap (extracts a given iso surface from a 3D scalar map), CutPlane (cuts a 3D
scalar map with a plane section), CutSphere (cuts a 3D scalar map with a
sphere); various other bug fixes, additions and clean-ups.

1.21 (Jul 25, 2001): fixed more memory leaks; added -opt command line option to
parse definitions directly from the command line; fixed missing screen refreshes
during contour/surface/volume selection; enhanced string manipulation functions
(Sprintf, StrCat, StrPrefix); many other small fixes and clean-ups.

1.20 (Jun 14, 2001): fixed various bugs (memory leaks, functions in included
files, solver command selection, ColorTable option, duplicate nodes in extruded
meshes (not finished yet), infinite loop on empty views, orientation of
recombined quadrangles, ...); reorganized the interface menus; added constrained
background mesh and mesh visibility options; added mesh quality histograms;
changed default mesh colors; reintegrated the old command-line extrusion mesh
generator.

1.19 (May 07, 2001): fixed seg. fault for scalar simplex post-processing; new
Solver menu; interface for GetDP solver through sockets; fixed multiple scale
alignment; added some options + full option descriptions.

1.18 (Apr 26, 2001): fixed many small bugs and incoherences in post-processing;
fixed broken background mesh in 1D mesh generation.

1.17 (Apr 17, 2001): corrected physical points saving; fixed parsing of DOS
files (carriage return problems); easier geometrical selections (cursor change);
plugin manager; enhanced variable arrays (sublist selection and affectation);
line loop check; New arrow display; reduced number of 'fatal' errors + better
handling in interactive mode; fixed bug when opening meshes; enhanced File->Open
behavior for meshes and post-processing views.

1.16 (Feb 26, 2001): added single/double buffer selection (only useful for Unix
versions of Gmsh run from remote hosts without GLX); fixed a bug for recent
versions of the opengl32.dll on Windows, which caused OpenGL fonts not to show
up.

1.15 (Feb 23, 2001): added automatic visibility setting during entity selection;
corrected geometrical extrusion bug.

1.14 (Feb 17, 2001): corrected a few bugs in the GUI (most of them were
introduced in 1.13); added interactive color selection; made the option database
bidirectional (i.e. scripts now correctly update the GUI); default options can
now be saved and automatically reloaded at startup; made some changes to the
scripting syntax (PostProcessing.View[n] becomes View[n]; Offset0 becomes
OffsetX, etc.); corrected the handling of simple triangular surfaces with large
characteristic lengths in the 2D isotropic algorithm; added an ASCII to binary
post-processing view converter.

1.13 (Feb 09, 2001): added support for JPEG output on Windows.

1.12: corrected vector lines in the post-processing parsed format; corrected
animation on Windows; corrected file creation in scripts on Windows; direct
affectation of variable arrays.

1.11 (Feb 07, 2001): corrected included file loading problem.

1.10 (Feb 04, 2001): switched from Motif to FLTK for the GUI. Many small tweaks.

1.00 (Jan 15, 2001): added PPM and YUV output; corrected nested If/Endif;
Corrected several bugs for pixel output and enhanced GIF output (dithering,
transparency); slightly changed the post-processing file format to allow both
single and double precision numbers.

0.999 (Dec 20, 2000): added JPEG output and easy MPEG generation (see t8.geo in
the tutorial); clean up of export functions; small fixes; Linux versions are now
compiled with gcc 2.95.2, which should fix the problems encountered with
Mandrake 7.2.

0.998 (Dec 19, 2000): corrected bug introduced in 0.997 in the generation of the
initial 3D mesh.

0.997 (Dec 14, 2000): corrected bug in interactive surface/volume selection;
Added interactive symmetry; corrected geometrical extrusion with rotation in
degenerated or partially degenerated cases; corrected bug in 2D mesh when
meshing in the mean plane.

0.996: arrays of variables; enhanced Printf and Sprintf; Simplified options
(suppression of option arrays).

0.995 (Dec 11, 2000): totally rewritten geometrical database (performance has
been drastically improved for all geometrical transformations, and most notably
for extrusion). As a consequence, the internal numbering of geometrical entities
has changed: this will cause incompatibilities with old .geo files, and will
require a partial rewrite of your old .geo files if these files made use of
geometrical transformations. The syntax of the .geo file has also been
clarified. Many additions for scripting purposes. New extrusion mesh
generator. Preliminary version of the coupling between extruded and Delaunay
meshes. New option and procedural database. All interactive operations can be
scripted in the input files. See the last example in the tutorial for an
example. Many stability enhancements in the 2D and 3D mesh
algorithms. Performance boost of the 3D algorithm. Gmsh is still slow, but the
performance becomes acceptable. An average 1000 tetrahedra/second is obtained on
a 600Mhz computer for a mesh of one million tetrahedra. New anisotropic 2D mesh
algorithm. New (ASCII and binary) post-processing file format and clarified mesh
file format. New handling for interactive rotations (trackball mode). New
didactic interactive mesh construction (watch the Delaunay algorithm in real
time on complex geometries: that's exciting ;-). And many, many bug fixes and
cleanups.

0.992 (Nov 13, 2000): corrected recombined extrusion; corrected ellipses; added
simple automatic animation of post-processing maps; fixed various bugs.

0.991 (Oct 24, 2000): fixed a serious allocation bug in 2D algorithm, which
caused random crashes. All users should upgrade to 0.991.

0.990: bug fix in non-recombined 3D transfinite meshes.

0.989 (Sep 01, 2000): added ability to reload previously saved meshes; some new
command line options; reorganization of the scale menu; GIF output.

0.987: fixed bug with smoothing (leading to the possible generation of erroneous
3d meshes); corrected bug for mixed 3D meshes; moved the 'toggle view link'
option to Opt->Postprocessing_Options.

0.986: fixed overlay problems; SGI version should now also run on 32 bits
machines; fixed small 3d mesh bug.

0.985: corrected colormap bug on HP, SUN, SGI and IBM versions; corrected small
initialization bug in postscript output.

0.984: corrected bug in display lists; added some options in Opt->General.

0.983: corrected some seg. faults in interactive mode; corrected bug in
rotations; changed default window sizes for better match with 1024x768 screens
(default X resources can be changed: see ex03.geo).

0.982: lighting for mesh and post-processing; corrected 2nd order mesh on non
plane surfaces; added example 13.