Don't need no stinking S_TEX3D special case, it's just part of the general case now.

src/specks.h

@@ -79,7 +79,7 @@ struct AMRbox {
 };
 
 enum SurfStyle {
-  S_SOLID, S_LINE, S_PLANE, S_POINT, S_OFF, S_TEX3D
+  S_SOLID, S_LINE, S_PLANE, S_POINT, S_HALO, S_OFF
 };
 
 enum MeshType {
@@ -113,6 +113,7 @@ struct mesh {
   Point *vnorms;	/* vnorms[nvnorms] vertex normals, or NULL */
   Point *fnorms;	/* fnorms[nfnorms] facet normals, or NULL if absent */
   Point *fcolors;	/* fcolors[nfaces] RGB colors stored in Point's, or NULL if absent */
+  float haloth;		/* halo threshold */
 };
 
 struct ellipsoid {