Add a useful package (from Source forge) for octave

[CreaPhase.git] / octave_packages / vrml-1.0.13 / vrml_arrow.m

diff --git a/octave_packages/vrml-1.0.13/vrml_arrow.m b/octave_packages/vrml-1.0.13/vrml_arrow.m
new file mode 100644 (file)
index 0000000..949fd95
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+++ b/octave_packages/vrml-1.0.13/vrml_arrow.m
@@ -0,0 +1,118 @@
+## Copyright (C) 2002-2012 Etienne Grossmann <etienne@egdn.net>
+##
+## 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/>.
+
+## s = vrml_arrow (sz, col)     - Arrow pointing in "y" direction
+##
+## INPUT :
+## -------
+## Arguments are optional. NaN's are replaced by default values.
+##                                                         <default>
+## sz = [len, alen, dc, dr] has size 1, 2, 3 or 4, where
+##
+##   len  : total length                                   <1>
+##   alen : If positive: length of cone/total length       <1/4>
+##          If negative: -(length of cone)
+##   dc   : If positive: diameter of cone base/total len   <1/16>
+##          If negative: -(diameter of cone) 
+##   dr   : If positive: diameter of rod/total length      <min(dc, len/32)>
+##          If negative: -(diameter of rod) 
+##
+## col    : 3 or 3x2 : Color of body and cone              <[0.3 0.4 0.9]>
+##
+## OUTPUT :
+## --------
+## s      : string   : vrml representation of an arrow (a rod and a cone)
+
+function v = vrml_arrow (sz, col, emit)
+
+if nargin < 3, emit = 1; end
+
+if nargin<2  || isempty (col),    col = [0.3 0.4 0.9;0.3 0.4 0.9];
+elseif prod (size (col)) == 3,    col = [1;1]*col(:)';
+elseif all (size (col) == [3,2]), col = col';
+elseif any (size (col) != [2,3]),
+  error("vrml_arrow : col has size %dx%d (should be 3 or 3x2)\n",size(col));
+  ## keyboard
+end
+col = col' ;
+
+s0 = [1, 1/4, 1/16, 1/32];
+                               # Get absolute size
+if nargin<1 || isempty (sz) || isnan (sz),  sz = s0 ;
+elseif length (sz) == 4,      sz = [sz(1),sz(2),sz(3),sz(4)];
+elseif length (sz) == 3,      sz = [sz(1),sz(2),sz(3),s0(4)];
+elseif length (sz) == 2,      sz = [sz(1),sz(2),s0(3),s0(4)];
+elseif length (sz) == 1,      sz = [sz(1),s0(2),s0(3),s0(4)];
+else 
+  error ("vrml_arrow : sz has size %dx%d. (should be in 1-4)\n", size(sz));
+  ## keyboard
+end
+
+assert (sz(1) > 0)
+
+if !isempty (tmp = find(isnan(sz))), sz(tmp) = s0(tmp) ; end
+
+for i = 2:4
+  if sz(i) >= 0
+       sz(i) *= sz(1);
+  else
+       sz(i) = -sz(i);
+  endif
+endfor
+
+                               # Do material nodes
+smat1 = vrml_material (col(:,1), emit);
+smat2 = vrml_material (col(:,2), emit);
+
+v = sprintf (["Group {\n",\
+              "  children [\n",\
+              "    Transform {\n",\
+              "      translation  %8.3g %8.3g %8.3g\n",\
+              "      children [\n",\
+              "        Shape {\n",\
+              "          appearance Appearance {\n",\
+             smat1,\
+             "          }\n"\
+              "          geometry Cylinder {\n",\
+             "            radius %8.3g\n",\
+             "            height %8.3g\n",\
+             "          }\n",\
+              "        }\n",\
+              "      ]\n",\
+              "    }\n",\
+              "    Transform {\n",\
+              "      translation  %8.3g %8.3g %8.3g\n",\
+              "      children [\n",\
+              "        Shape {\n",\
+              "          appearance Appearance {\n",\
+             smat2,\
+              "          }\n",\
+              "          geometry Cone { \n",\
+              "            bottomRadius  %8.3g \n",\
+              "            height  %8.3g\n",\
+              "          }\n",\
+              "        }\n",\
+              "      ]\n",\
+              "    }\n",\
+              "  ]\n",\
+              "}\n"],\
+            [0,(sz(1)-sz(2))/2,0],\
+            sz(4),\
+            sz(1)-sz(2),\
+            [0,sz(2)/2+sz(1)-sz(2),0],\
+            sz(3),\
+            sz(2));
+endfunction
+