access global lc in options

Common/DefaultOptions.h

@@ -346,6 +346,8 @@ StringXNumber GeneralOptions_Number[] = {
   { F|O, "BackgroundImageHeight" , opt_general_background_image_size1 , -1 ,
     "Height of background image (0: actual height if width = 0, natural scaling if not; "
     "-1: graphic window height)" },
+  { F|O, "BoundingBoxeSize" , opt_general_lc, 1. ,
+    "Overall bounding box size (read-only)" },
 
   { F|O, "Camera" , opt_general_camera_mode, 0. ,
     "Enable camera view mode" },

Common/Options.cpp

@@ -2803,6 +2803,11 @@ double opt_general_zmax(OPT_ARGS_NUM)
   return bb.empty() ? 0. : bb.max().z();
 }
 
+double opt_general_lc(OPT_ARGS_NUM)
+{
+  return CTX::instance()->lc;
+}
+
 double opt_general_axes(OPT_ARGS_NUM)
 {
   if(action & GMSH_SET){

Common/Options.h

@@ -210,6 +210,7 @@ double opt_general_ymin(OPT_ARGS_NUM);
 double opt_general_ymax(OPT_ARGS_NUM);
 double opt_general_zmin(OPT_ARGS_NUM);
 double opt_general_zmax(OPT_ARGS_NUM);
+double opt_general_lc(OPT_ARGS_NUM);
 double opt_general_axes(OPT_ARGS_NUM);
 double opt_general_axes_mikado(OPT_ARGS_NUM);
 double opt_general_axes_auto_position(OPT_ARGS_NUM);