change default surface representation to "cross", even for OpenCASCADE models;

this is a temporary workaround for a bug in OpenCASCADE, which fails to triangulate quite a few surfaces (it just hangs, which freezes our GUI)

Common/DefaultOptions.h

@@ -913,7 +913,7 @@ StringXNumber GeometryOptions_Number[] = {
     "Display geometry surfaces?" },
   { F|O, "SurfaceNumbers" , opt_geometry_surfaces_num , 0. ,
     "Display surface numbers?" },
-  { F|O, "SurfaceType" , opt_geometry_surface_type , 2. ,
+  { F|O, "SurfaceType" , opt_geometry_surface_type , 0. ,
     "Surface display type (0=cross, 1=wireframe, 2=solid)" },
 
   { F|O, "Tangents" , opt_geometry_tangents , 0. ,

Fltk/contextWindow.cpp

@@ -56,10 +56,10 @@ static void draw_stl(std::vector<SPoint3> &vertices, std::vector<SVector3> &norm
 {
   GLint mode[2];
   glGetIntegerv(GL_POLYGON_MODE, mode);
-  if(CTX::instance()->geom.surfaceType > 1)
-    glPolygonMode(GL_FRONT_AND_BACK, GL_FILL);
-  else
+  if(CTX::instance()->geom.surfaceType == 1)
     glPolygonMode(GL_FRONT_AND_BACK, GL_LINE);
+  else
+    glPolygonMode(GL_FRONT_AND_BACK, GL_FILL);
   glEnable(GL_LIGHTING);
   glLightModelf(GL_LIGHT_MODEL_TWO_SIDE, GL_TRUE);
   glColor4ubv((GLubyte *) & CTX::instance()->color.geom.highlight[0]);