--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/scripts/plot/isocolors.m	Sat Apr 11 16:26:01 2009 +0200
@@ -0,0 +1,168 @@
+## Copyright (C) 2009 Martin Helm
+##
+## This program is free software; you can redistribute it and/or modify
+## it under the terms of the GNU General Public License as published by
+## the Free Software Foundation; either version 3 of the License, or
+## (at your option) any later version.
+##
+## This program is distributed in the hope that it will be useful,
+## but WITHOUT ANY WARRANTY; without even the implied warranty of
+## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+## GNU General Public License for more details.
+##
+## You should have received a copy of the GNU General Public License
+## along with this program; if not, see http://www.gnu.org/licenses/gpl.html.
+
+## -*- texinfo -*-
+## @deftypefn  {Function File} {[@var{cd}] =} isocolors (@var{c}, @var{v})
+## @deftypefnx {Function File} {[@var{cd}] =} isocolors (@var{x}, @var{y}, @var{z}, @var{c}, @var{v})
+## @deftypefnx {Function File} {[@var{cd}] =} isocolors (@var{x}, @var{y}, @var{z}, @var{r}, @var{g}, @var{b}, @var{v})
+## @deftypefnx {Function File} {[@var{cd}] =} isocolors (@var{r}, @var{g}, @var{b}, @var{v})
+## @deftypefnx {Function File} {[@var{cd}] =} isocolors (@dots{}, @var{p})
+## @deftypefnx {Function File} isocolors (@dots{})
+##
+## If called with one output argument and the first input argument
+## @var{c} is a three--dimensional array that contains color values and
+## the second input argument @var{v} keeps the vertices of a geometry
+## then return a matrix @var{cd} with color data information for the
+## geometry at computed points 
+## @command{[x, y, z] = meshgrid (1:l, 1:m, 1:n)}.  The output argument
+## @var{cd} can be taken to manually set FaceVertexCData of a patch.
+##
+## If called with further input arguments @var{x}, @var{y} and @var{z}
+## which are three--dimensional arrays of the same size than @var{c}
+## then the color data is taken at those given points.  Instead of the
+## color data @var{c} this function can also be called with RGB values
+## @var{r}, @var{g}, @var{b}.  If input argumnets @var{x}, @var{y},
+## @var{z} are not given then again @command{meshgrid} computed values
+## are taken.
+##
+## Optionally, the patch handle @var{p} can be given as the last input
+## argument to all variations of function calls instead of the vertices
+## data @var{v}.  Finally, if no output argument is given then directly
+## change the colors of a patch that is given by the patch handle
+## @var{p}.
+##
+## For example,
+## @example
+## function [] = isofinish (p)
+##   set (gca, "DataAspectRatioMode", "manual", \
+##        "DataAspectRatio", [1 1 1]);
+##   set (p, "FaceColor", "interp");
+##   ## set (p, "FaceLighting", "flat");
+##   ## light ("Position", [1 1 5]); ## Available with JHandles
+## endfunction
+## 
+## N = 15;    ## Increase number of vertices in each direction
+## iso = .4;  ## Change isovalue to .1 to display a sphere
+## lin = linspace (0, 2, N);
+## [x, y, z] = meshgrid (lin, lin, lin);
+## c = abs ((x-.5).^2 + (y-.5).^2 + (z-.5).^2); 
+## figure (); ## Open another figure window
+##
+## subplot (2, 2, 1); view (-38, 20); 
+## [f, v] = isosurface (x, y, z, c, iso);
+## p = patch ("Faces", f, "Vertices", v, "EdgeColor", "none");
+## cdat = rand (size (c));       ## Compute random patch color data
+## isocolors (x, y, z, cdat, p); ## Directly set colors of patch
+## isofinish (p);                ## Call user function isofinish
+##
+## subplot (2, 2, 2); view (-38, 20); 
+## p = patch ("Faces", f, "Vertices", v, "EdgeColor", "none");
+## [r, g, b] = meshgrid (lin, 2-lin, 2-lin);
+## cdat = isocolors (x, y, z, c, v); ## Compute color data vertices
+## set (p, "FaceVertexCData", cdat); ## Set color data manually
+## isofinish (p);
+##
+## subplot (2, 2, 3); view (-38, 20); 
+## p = patch ("Faces", f, "Vertices", v, "EdgeColor", "none");
+## cdat = isocolors (r, g, b, c, p); ## Compute color data patch
+## set (p, "FaceVertexCData", cdat); ## Set color data manually
+## isofinish (p);
+##
+## subplot (2, 2, 4); view (-38, 20); 
+## p = patch ("Faces", f, "Vertices", v, "EdgeColor", "none");
+## r = g = b = repmat ([1:N] / N, [N, 1, N]); ## Black to white
+## cdat = isocolors (x, y, z, r, g, b, v);
+## set (p, "FaceVertexCData", cdat);
+## isofinish (p);
+## @end example
+##
+## @seealso{isosurface, isonormals, isocaps}
+##
+## @end deftypefn
+
+## Author: Martin Helm <martin@mhelm.de>
+
+function varargout = isocolors(varargin)
+  calc_rgb = false;
+  switch nargin
+    case 2
+      c = varargin{1};
+      vp = varargin{2};
+      x = 1:size (c, 2);
+      y = 1:size (c, 1);
+      z = 1:size (c, 3);
+    case 4
+      calc_rgb = true;
+      R = varargin{1};
+      G = varargin{2};
+      B = varargin{3};
+      vp = varargin{4};
+      x = 1:size (R, 1);
+      y = 1:size (R, 2);
+      z = 1:size (R, 3);
+    case 5
+      x = varargin{1};
+      y = varargin{2};
+      z = varargin{3};
+      c = varargin{4};
+      vp = varargin{5};
+    case 7
+      calc_rgb = true;
+      x = varargin{1};
+      y = varargin{2};
+      z = varargin{3};
+      R = varargin{4};
+      G = varargin{5};
+      B = varargin{6};
+      vp = varargin{7};
+    otherwise 
+      print_usage ();
+  endswitch
+  if (ismatrix (vp) && size (vp,2) == 3)
+    pa = [];
+    v = vp;
+  elseif ( ishandle (vp) )
+    pa = vp;
+    v = get (pa, "Vertices");
+  else
+    error("Last argument is no vertex list and no patch handle");
+  endif
+  if ( calc_rgb )
+    new_col = zeros (size (v, 1), 3);
+    new_col(:, 1) = __interp_cube__ (x, y, z, R, v, "values" );
+    new_col(:, 2) = __interp_cube__ (x, y, z, G, v, "values" );
+    new_col(:, 3) = __interp_cube__ (x, y, z, B, v, "values" );
+  else
+    new_col = __interp_cube__ (x, y, z, c, v, "values" );
+  endif
+  switch nargout
+    case 0
+      if (!isempty (pa))
+        set (pa, "FaceVertexCData", new_col);
+      endif
+    case 1
+      varargout = {new_col};
+    otherwise
+      print_usage ();
+  endswitch
+endfunction
+
+%!test
+%!  [x, y, z] = meshgrid (0:.5:2, 0:.5:2, 0:.5:2);
+%!  c = (x-.5).^2 + (y-.5).^2 + (z-.5).^2; 
+%!  [f, v] = isosurface (x, y, z, c, .4);
+%!  cdat = isocolors (x, y, z, c, v);
+%!  assert (size (cdat, 1) == size (v, 1));
+## Can't create a patch handle for tests without a figure