vrml_arrow

(tmp_for_tar/vrml.doc/vrml_arrow.m)

Function Synopsis

v = vrml_arrow(sz, col)

Help text

       v = vrml_arrow (sz, col) - Arrow pointing in "y" direction

 sz = [len, alen, dc, dr] has size 1, 2, 3 or 4, where
   len  : total length                         default : 1
   alen : length of arrow/total length         default : 1/4
   dc   : Diameter of cone base/total length   default : 1/12
   dr   : Diameter of rod/total length         default : min(dc, sz(1)/24)

   NaN's in sz will be replaced by default value.

 col    : 3 or 2x3 : Color of body and cone    default : [0.3 0.4 0.9]

 Last modified: December 2000

Cross-Reference Information

vrml_frame     tmp_for_tar/vrml.doc/vrml_frame.m

Listing of function file tmp_for_tar/vrml.doc/vrml_arrow.m

##       v = vrml_arrow (sz, col) - Arrow pointing in "y" direction
##
## sz = [len, alen, dc, dr] has size 1, 2, 3 or 4, where
##   len  : total length                         default : 1
##   alen : length of arrow/total length         default : 1/4
##   dc   : Diameter of cone base/total length   default : 1/12
##   dr   : Diameter of rod/total length         default : min(dc, sz(1)/24)
##
##   NaN's in sz will be replaced by default value.
##
## col    : 3 or 2x3 : Color of body and cone    default : [0.3 0.4 0.9]
##

## Author:        Etienne Grossmann  <etienne@isr.ist.utl.pt>
## Last modified: December 2000

function v = vrml_arrow(sz, col)


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]),
  printf ("vrml_arrow : col has size %d x %d. This won't do\n",size(col));
  keyboard
end
col = col' ;

s0 = [1, 1/4, 1/16, 1/32];
				# Get absolute size
if nargin<1 || isempty (sz),  sz = s0 ;

elseif length (sz) == 4,      sz = sz(1)*[1,sz(2),sz(3),sz(4)];
elseif length (sz) == 3,      sz = sz(1)*[1,sz(2),sz(3),s0(4)];
elseif length (sz) == 2,      sz = sz(1)*[1,sz(2),s0(3),s0(4)];
elseif length (sz) == 1,      sz = sz   *s0;
else 
  printf ("vrml_arrow : sz has size %d x %d. This won't do\n",size(sz));
  keyboard
end
if any (tmp = isnan(sz)), sz(find (tmp)) = s0(find (tmp)) ; end

v = sprintf (["Group {\n",\
              "  children [\n",\
              "    Transform {\n",\
              "      translation  %8.3g %8.3g %8.3g\n",\
              "      children [\n",\
              "        Shape {\n",\
              "          appearance Appearance {\n",\
              "            material Material { diffuseColor %8.3g %8.3g %8.3g }\n",\
              "          }\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",\
              "            material Material { diffuseColor  %8.3g %8.3g %8.3g }\n",\
              "          }\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],\
	     col(1:3),\
	     sz(4),\
	     sz(1)-sz(2),\
	     [0,sz(2)/2+sz(1)-sz(2),0],\
	     col(4:6),\
	     sz(3),\
	     sz(2));