my last commit also fixed several problems in For/EndFor loops:

- the body of the loop was executed at least once, even if the test was
  always false (e.g. For (1:-1:1) )
- the body could be executed one extra time when using optional
  step values
- the for loops didn't work with negative step values

- new parser function GetValue("text", default_value) to query a value
  interactively in a script

- added a nice example using this (to compute slices automatically):
  demos/multislice.script

- new "Delete Empty Views" command
- new View.MinX, View.MinY, View.MinZ, View.MaxX, View.MaxY, View.MaxZ options
- added example on how to do simple volume visualization

- fix cast in a couple of error msg
- more fixes in elliptic algorithm (surf->TrsfVertices and surf->Vertices
  were incomplete)

one can now specify a TIME list of values in parsed views to give the
values of the time (or whatever) steps (like in ascii/binary views)

- moved the AdaptiveView stuff in its own header file

- fixed small bug in IsoSimplex (when Raise != 0)

- fixed small memory leak in Plugin/Extract (when one or more
  expressions are invalid)

- Added a bunch of colormaps from:

  Color Theory and Modeling for
  Computer Graphics, Visualization,
  and Multimedia Applications

  Haim Levkowitz
  University of Massachusetts Lowell
  Lowell, Massachusetts, USA

- Increased max size of colormap to 1024

- Small cleanup in parser+plugin

This patch fixes an old design flaw in the post-processing module,
namely that we used a list of Post_View objects instead of a list of
pointers to Post_View objects in CTX.post.list.

This had many annoying consequences, in particular the fact that we
needed to be extra careful every time the list was reallocated (as
pointers to the list elements would become invalid).

I tried very hard to change the code everywhere it should be changed,
but I might have missed something. Please let me know if you see
anything suspicious (like a crash when you duplicate/remove/combine/...
post-processing views).

fixed error checking code to work also with adaptive views.

cleanup (and remove 2 shift/reduce conflicts in parser)

proof of concept for unproject (e.g. to add points with the mouse)

- make the rotation matrix a matrix of doubles (instead of floats)

- store the modelview and the projection matrices in CTX

- new unproject() routine to transform window coordinates to model
  coordinates

- cleaned up all the static variables in the Opengl_Window class

- small fix to reduce normal clamping when zooming

if we have no geometry and no mesh, use the max of all view bounding boxes
(instead of the bounding box of the last view only)

small fixes for last commit:

- only delete view.adaptive if we really delete the view (we might want to
  use the adaptive data in a duplicate view)

- add missing opt_view_global_zoom in update_view()

- don't even try to open StructuralSolver's data files if GMSHPLUGINSHOME
  is not defined

New high order interpolation.

JFR

Trying to fix Patrick's problems when launching getdp on Windows...

When gmsh is started from the command line on Windows, cygwin does
not (for some obscure reason) prepend '/cygdrive/x/' to the path. Since
we check for '/cygdrive/' in SystemCall() in order to sanitize the
path before passing it to CreateProcess(), the system call fails.

I think the right way to deal with this is to actually remove the
path change in SystemCall() (since we only change the leading part),
and use the official cygwin API to change the path of every piece
that will eventually end up in the argument of CreateProcess().
And that's what "FixWindowsPath()" now does...

forgot to commit this

added ability to save views in "parsed" format

subclass the original file chooser and move it into the GUI class, so
that we can set its position (the FLTK folks don't want to patch the
standard file chooser, so this is the only solution...)

generalized the "spatial" Combine so that we can also combine by view name

cleaned up View->Combine by defining a new option (to determine if
we should remove the original views after a "Combine" or not)

speedup view removal (only call UpdateViewsInGUI once per group of
deletions)

Changed the order in which we compute the bounding box of a scene: look
for mesh vertices first, then look for geometry points. I think this is better,
since more and more people use the code just to visualize meshes (without
geometries); as soon as there was one physical point in the mesh, the resulting
bb could seem strange (as the physical points create geometrical points).

- set glBlendEquation explicitly
- make parser

old comment

make depend

make depend

force a buffer flush when we abort the parser due to too many errors

- All extrusion commands now return a list of 2 numbers (instead of 1):
  the first, as before, is the number of the "top" of the extruded region
  (i.e., a point for extrude point, a line for extrude line, ...), the
  second is the number of the "body" of the extruded region (i.e., a
  line for extrude point, a surface for extrude line, ...).

- "Extrude Surface" now always creates a new volume (automatically),
  EVEN WHEN THERE IS NO LAYERS SPECIFICATION. This makes it consistent
  with "Extrude Point" and "Extrude Line", which always create new
  curves and surfaces, respectively.

  Important Note: you will have to modify your old .geo files to avoid
  duplicate volume definitions if you use "Extrude Surface" without
  extruding the mesh (i.e., without the "Layers" command). These
  duplicate volumes would be harmless, but they would srew up your
  physical volume definitions later on...

  * Solution 1: use the new volumes (recommended). To do this, just
  remove your old extra volume definitions and let Gmsh create the
  extruded volumes for you. (To retrieve the volume number created by
  Gmsh, use "aa[] = Extrude Surface {...};;": the volume number is
  "aa[1]".)

  * Solution 2: keep the old volumes.

  a) clean way: retrieve the new volume number (aa[] = Extrude Surface
  {...};;) and delete the new volume with "Delete { Volume aa[1]; }"

  b) dirty (but handy) way: since, in order to create the new volumes
  with the less impact possible, Gmsh uses "low" numbers (actually,
  forcing "Geometry.OldNewreg=0") for the new volumes, just remove all
  "low number volumes". For example, if you have 4 "Extrude Surface" in
  your file, you can then just do "Delete{ Volume {1:4}; }"

Voila :-)

bulletproof FindCurve/Surface + uniformize error messages

create the default project file in the home directory if no "current"
directory is defined (e.g. when double-clicking on the icon on Windows/MacOS)

add @. after color specs in Fl_Browser: otherwise strings that start
with a digit don't get printed

- set VectorType to Displacement in Plugin(StreamLines)
- shout when a plugin option/name does not exist

new BoundingBox command to force the computation of the bounding box (useful
when there is no geometry and we don't include/merge any views)

- generalized vertex arrays to handle quads

- added missing Ellispe ... Plane ... in parser

- generalized vertex array class to use reallocatable arrays

- introduced vertex arrays in post for all triangles: this speeds
  things up tremendously for ALL scalar views: 2d scalar views of
  course, but also for 3d isos (tets, hexas, etc.) and all smooth
  normals. The costly computations (compute the isos, get the normals)
  are only done ONCE each time the view is changed. Then we just pass
  the vertex array to OpenGL everytime we need to redraw (e.g. when we
  rotate the scene)

- removed the display list code alltogether: it's completely blown
  away by the new vertex array code!

for the record: with the new drawing code, you can

- rotate 500,000 triangles in real time on a 3-year old linux PC
(tested with a boing 747 surface mesh from CU: 10 times faster than
old code)

- display and rotate in real time 10 transparent+smooth shaded 3D isos
for a 1 million tet mesh (about 1 frame per second with the new code;
took tens of seconds with the old one)

Awesome :-)