diff --git a/Makefile b/Makefile
index d74aade6..5f36d265 100644
--- a/Makefile
+++ b/Makefile
@@ -83,7 +83,7 @@ ifeq (${TOOLCHAIN},clang)
   CXXFLAGS_STD = -std=c++11
   CXXFLAGS_EARLY += -march=native -fPIC
   CXXFLAGS_EARLY += -W -Wall -Wextra -Werror -pedantic
-  CXXFLAGS_EARLY += -Wno-unused-parameter -Wno-implicit-fallthrough -Wno-maybe-uninitialized -Wno-unknown-warning-option
+  CXXFLAGS_EARLY += -Wno-unused-parameter -Wno-implicit-fallthrough -Wno-maybe-uninitialized -Wno-unknown-warning-option -Wno-overloaded-virtual
 endif
 
 ifeq (${TOOLCHAIN},gcc)
diff --git a/config.cpp b/config.cpp
index f91e60dd..993629d4 100644
--- a/config.cpp
+++ b/config.cpp
@@ -27,9 +27,9 @@ struct supersaver {
   virtual void load(const string& s) = 0;
   virtual bool dosave() = 0;
   virtual void reset() = 0;
-  virtual ~supersaver() {}
   virtual bool affects(void* v) { return false; }
   virtual void set_default() = 0;
+  virtual ~supersaver() = default;
   };
 
 typedef vector<shared_ptr<supersaver>> saverlist;
@@ -56,7 +56,7 @@ struct setting {
     return parameter_name + "|" + config_name + "|" + menu_item_name + "|" + help_text;
     }
   virtual cld get_cld() = 0;
-  setting() { restrict = auto_restrict; is_editable = false; }
+  explicit setting() { restrict = auto_restrict; is_editable = false; }
   virtual void check_change() {
     cld val = get_cld();
     if(val != last_value) {
@@ -68,7 +68,7 @@ struct setting {
   setting *set_sets(const reaction_t& s) { sets = s; return this; }
   setting *set_extra(const reaction_t& r);
   setting *set_reaction(const reaction_t& r);
-  virtual ~setting() {}
+  virtual ~setting() = default;
   virtual void load_from(const string& s) {
     println(hlog, "cannot load this parameter");
     exit(1);
@@ -100,7 +100,7 @@ struct list_setting : setting {
     default_key = key;
     return this;
     }
-  virtual void show_edit_option(char key) override;
+  void show_edit_option(char key) override;
   };
 
 template<class T> struct enum_setting : list_setting {
@@ -108,10 +108,10 @@ template<class T> struct enum_setting : list_setting {
   T dft;
   int get_value() override { return (int) *value; }
   void set_value(int i) override { *value = (T) i; }
-  virtual bool affects(void* v) override { return v == value; }
-  virtual void add_as_saver() override;
-  virtual cld get_cld() override { return get_value(); }
-  virtual void load_from(const string& s) override {
+  bool affects(void* v) override { return v == value; }
+  void add_as_saver() override;
+  cld get_cld() override { return get_value(); }
+  void load_from(const string& s) override {
     *value = (T) parseint(s);
     }
   };
@@ -134,11 +134,10 @@ struct float_setting : public setting {
   function<void(float_setting*)> modify_me;
   float_setting *modif(const function<void(float_setting*)>& r) { modify_me = r; return this; }
   void add_as_saver() override;
-  virtual bool affects(void *v) override { return v == value; }
-  virtual void show_edit_option(char key) override;
-  virtual cld get_cld() override { return *value; }
-
-  virtual void load_from(const string& s) override;
+  bool affects(void *v) override { return v == value; }
+  void show_edit_option(char key) override;
+  cld get_cld() override { return *value; }
+  void load_from(const string& s) override;
   };
 
 struct int_setting : public setting {
@@ -149,9 +148,9 @@ struct int_setting : public setting {
   void add_as_saver() override;
   function<void(int_setting*)> modify_me;
   int_setting *modif(const function<void(int_setting*)>& r) { modify_me = r; return this; }
-  virtual bool affects(void *v) override { return v == value; }
-  virtual void show_edit_option(char key) override;
-  virtual cld get_cld() override { return *value; }
+  bool affects(void *v) override { return v == value; }
+  void show_edit_option(char key) override;
+  cld get_cld() override { return *value; }
   int_setting *editable(int min_value, int max_value, ld step, string menu_item_name, string help_text, char key) {
     this->min_value = min_value;
     this->max_value = max_value;
@@ -162,7 +161,7 @@ struct int_setting : public setting {
     return this;
     }
 
-  virtual void load_from(const string& s) override {
+  void load_from(const string& s) override {
     *value = parseint(s);
     }
   };
@@ -176,10 +175,10 @@ struct bool_setting : public setting {
     is_editable = true;
     menu_item_name = cap; default_key = key; return this; 
     } 
-  virtual bool affects(void *v) override { return v == value; }
-  virtual void show_edit_option(char key) override;
-  virtual cld get_cld() override { return *value ? 1 : 0; }
-  virtual void load_from(const string& s) override {
+  bool affects(void *v) override { return v == value; }
+  void show_edit_option(char key) override;
+  cld get_cld() override { return *value ? 1 : 0; }
+  void load_from(const string& s) override {
     *value = parseint(s);
     }
   };
@@ -188,9 +187,9 @@ struct custom_setting : public setting {
   function<void(char)> custom_viewer;
   function<cld()> custom_value;
   function<bool(void*)> custom_affect;
-  virtual void show_edit_option(char key) override { custom_viewer(key); }
-  virtual cld get_cld() override { return custom_value(); }
-  virtual bool affects(void *v) override { return custom_affect(v); }
+  void show_edit_option(char key) override { custom_viewer(key); }
+  cld get_cld() override { return custom_value(); }
+  bool affects(void *v) override { return custom_affect(v); }
   };
   
 #if CAP_CONFIG
@@ -198,11 +197,11 @@ struct custom_setting : public setting {
 template<class T> struct dsaver : supersaver {
   T& val;
   T dft;
-  bool dosave() { return val != dft; }
-  void reset() { val = dft; }
-  dsaver(T& val) : val(val) { }
-  bool affects(void* v) { return v == &val; }
-  void set_default() { dft = val; }
+  bool dosave() override { return val != dft; }
+  void reset() override { val = dft; }
+  explicit dsaver(T& val) : val(val) { }
+  bool affects(void* v) override { return v == &val; }
+  void set_default() override { dft = val; }
   };
 
 template<class T> struct saver : dsaver<T> {};
@@ -233,13 +232,13 @@ template<class T> void set_saver_default(T& val) {
 template<class T> struct saverenum : supersaver {
   T& val;
   T dft;
-  bool dosave() { return val != dft; }
-  void reset() { val = dft; }
-  saverenum<T>(T& v) : val(v) { }
-  string save() { return its(int(val)); }
-  void load(const string& s) { val = (T) atoi(s.c_str()); }
-  virtual bool affects(void* v) { return v == &val; }
-  virtual void set_default() { dft = val; }
+  explicit saverenum(T& v) : val(v) { }
+  bool dosave() override { return val != dft; }
+  void reset() override { val = dft; }
+  string save() override { return its(int(val)); }
+  void load(const string& s) override { val = (T) atoi(s.c_str()); }
+  bool affects(void* v) override { return v == &val; }
+  void set_default() override { dft = val; }
   };
 
 template<class T, class U> void addsaverenum(T& i, U name, T dft) {
@@ -254,39 +253,39 @@ template<class T, class U> void addsaverenum(T& i, U name) {
   }
 
 template<> struct saver<int> : dsaver<int> {
-  saver<int>(int& val) : dsaver<int>(val) { }
-  string save() { return its(val); }
-  void load(const string& s) { val = atoi(s.c_str()); }
+  explicit saver(int& val) : dsaver<int>(val) { }
+  string save() override { return its(val); }
+  void load(const string& s) override { val = atoi(s.c_str()); }
   };
 
 template<> struct saver<char> : dsaver<char> {
-  saver<char>(char& val) : dsaver<char>(val) { }
-  string save() { return its(val); }
-  void load(const string& s) { val = atoi(s.c_str()); }
+  explicit saver(char& val) : dsaver<char>(val) { }
+  string save() override { return its(val); }
+  void load(const string& s) override { val = atoi(s.c_str()); }
   };
 
 template<> struct saver<bool> : dsaver<bool> {
-  saver<bool>(bool& val) : dsaver<bool>(val) { }
-  string save() { return val ? "yes" : "no"; }
-  void load(const string& s) { val = isize(s) && s[0] == 'y'; }
+  explicit saver(bool& val) : dsaver<bool>(val) { }
+  string save() override { return val ? "yes" : "no"; }
+  void load(const string& s) override { val = isize(s) && s[0] == 'y'; }
   };
 
 template<> struct saver<unsigned> : dsaver<unsigned> {
-  saver<unsigned>(unsigned& val) : dsaver<unsigned>(val) { }
-  string save() { return itsh(val); }
-  void load(const string& s) { val = (unsigned) strtoll(s.c_str(), NULL, 16); }
+  explicit saver(unsigned& val) : dsaver<unsigned>(val) { }
+  string save() override { return itsh(val); }
+  void load(const string& s) override { val = (unsigned) strtoll(s.c_str(), NULL, 16); }
   };
 
 template<> struct saver<string> : dsaver<string> {
-  saver<string>(string& val) : dsaver<string>(val) { }
-  string save() { return val; }
-  void load(const string& s) { val = s; }
+  explicit saver(string& val) : dsaver<string>(val) { }
+  string save() override { return val; }
+  void load(const string& s) override { val = s; }
   };
 
 template<> struct saver<ld> : dsaver<ld> {
-  saver<ld>(ld& val) : dsaver<ld>(val) { }
-  string save() { return fts(val, 10); }
-  void load(const string& s) { 
+  explicit saver(ld& val) : dsaver<ld>(val) { }
+  string save() override { return fts(val, 10); }
+  void load(const string& s) override {
     if(s == "0.0000000000e+000") ; // ignore!
     else val = atof(s.c_str()); 
     }
diff --git a/drawing.cpp b/drawing.cpp
index a1fb5b77..08e6b60a 100644
--- a/drawing.cpp
+++ b/drawing.cpp
@@ -56,7 +56,7 @@ struct drawqueueitem {
   virtual void draw() = 0;
   /** \brief Draw the object as background. */
   virtual void draw_back() {}
-  virtual ~drawqueueitem() {}
+  virtual ~drawqueueitem() = default;
   /** \brief When minimizing OpenGL calls, we need to group items of the same color, etc. together. This value is used as an extra sorting key. */
   virtual color_t outline_group() = 0;
   };
@@ -85,12 +85,12 @@ struct dqi_poly : drawqueueitem {
   hyperpoint intester;
   /** \brief temporarily cached data */
   float cache;
-  void draw();
+  void draw() override;
   #if CAP_GL
   void gldraw();
   #endif
-  void draw_back();
-  virtual color_t outline_group() { return outline; }
+  void draw_back() override;
+  color_t outline_group() override { return outline; }
   };
 
 /** \brief Drawqueueitem used to draw lines */
@@ -101,9 +101,9 @@ struct dqi_line : drawqueueitem {
   int prf;
   /** \brief width of this line */
   double width;
-  void draw();
-  void draw_back();
-  virtual color_t outline_group() { return color; }
+  void draw() override;
+  void draw_back() override;
+  color_t outline_group() override { return color; }
   };
 
 /** \brief Drawqueueitem used to draw strings, using sccreen coodinates */      
@@ -120,8 +120,8 @@ struct dqi_string : drawqueueitem {
   int frame;
   /** alignment (0-8-16) */
   int align;
-  void draw();
-  virtual color_t outline_group() { return 1; }
+  void draw() override;
+  color_t outline_group() override { return 1; }
   };
 
 /** Drawqueueitem used to draw circles, using screen coordinates */
@@ -134,16 +134,16 @@ struct dqi_circle : drawqueueitem {
   color_t fillcolor;
   /** \brief width of the circle */
   double linewidth;
-  void draw();
-  virtual color_t outline_group() { return 2; }
+  void draw() override;
+  color_t outline_group() override { return 2; }
   };
 
 /** \brief Perform an arbitrary action. May temporarily change the model, etc. */
 struct dqi_action : drawqueueitem {
   reaction_t action;
-  dqi_action(const reaction_t& a) : action(a) {}
-  void draw() { action(); }
-  virtual color_t outline_group() { return 2; }
+  explicit dqi_action(const reaction_t& a) : action(a) {}
+  void draw() override { action(); }
+  color_t outline_group() override { return 2; }
   };
 #endif
 
diff --git a/hprint.cpp b/hprint.cpp
index 6fcb5982..f3d1e1ff 100644
--- a/hprint.cpp
+++ b/hprint.cpp
@@ -122,25 +122,25 @@ struct hstream_exception : hr_exception { hstream_exception() {} };
 
 struct fhstream : hstream {
   color_t vernum;
-  virtual color_t get_vernum() override { return vernum; }
   FILE *f;
-  virtual void write_char(char c) override { write_chars(&c, 1); }
-  virtual void write_chars(const char* c, size_t i) override { if(fwrite(c, i, 1, f) != 1) throw hstream_exception(); }
-  virtual void read_chars(char* c, size_t i) override { if(fread(c, i, 1, f) != 1) throw hstream_exception(); }
-  virtual char read_char() override { char c; read_chars(&c, 1); return c; }
-  fhstream() { f = NULL; vernum = VERNUM_HEX; }
-  fhstream(const string pathname, const char *mode) { f = fopen(pathname.c_str(), mode); vernum = VERNUM_HEX; }
+  explicit fhstream() { f = NULL; vernum = VERNUM_HEX; }
+  explicit fhstream(const string pathname, const char *mode) { f = fopen(pathname.c_str(), mode); vernum = VERNUM_HEX; }
   ~fhstream() { if(f) fclose(f); }
+  color_t get_vernum() override { return vernum; }
+  void write_char(char c) override { write_chars(&c, 1); }
+  void write_chars(const char* c, size_t i) override { if(fwrite(c, i, 1, f) != 1) throw hstream_exception(); }
+  void read_chars(char* c, size_t i) override { if(fread(c, i, 1, f) != 1) throw hstream_exception(); }
+  char read_char() override { char c; read_chars(&c, 1); return c; }
   };
 
 struct shstream : hstream { 
   color_t vernum;
-  virtual color_t get_vernum() override { return vernum; }
   string s;
   int pos;
-  shstream(const string& t = "") : s(t) { pos = 0; vernum = VERNUM_HEX; }
-  virtual void write_char(char c) override { s += c; }
-  virtual char read_char() override { if(pos == isize(s)) throw hstream_exception(); return s[pos++]; }
+  explicit shstream(const string& t = "") : s(t) { pos = 0; vernum = VERNUM_HEX; }
+  color_t get_vernum() override { return vernum; }
+  void write_char(char c) override { s += c; }
+  char read_char() override { if(pos == isize(s)) throw hstream_exception(); return s[pos++]; }
   };
 
 inline void print(hstream& hs) {}
@@ -243,11 +243,11 @@ int SDL_GetTicks();
 struct logger : hstream {
   int indentation;
   bool doindent;
-  logger() { doindent = false; }
-  virtual void write_char(char c) { if(doindent) { doindent = false; 
+  explicit logger() { doindent = false; }
+  void write_char(char c) override { if(doindent) { doindent = false; 
     if(debugflags & DF_TIME) { int t = SDL_GetTicks(); if(t < 0) t = 999999; t %= 1000000; string s = its(t); while(isize(s) < 6) s = "0" + s; for(char c: s) special_log(c); special_log(' '); }
     for(int i=0; i<indentation; i++) special_log(' '); } special_log(c); if(c == 10) doindent = true; if(c == 10 && debugfile) fflush(debugfile); }
-  virtual char read_char() { throw hstream_exception(); }
+  char read_char() override { throw hstream_exception(); }
   };
 
 extern logger hlog;
@@ -278,11 +278,11 @@ inline void print(hstream& hs, cellwalker cw) {
 struct indenter {
   dynamicval<int> ind;
   
-  indenter(int i = 2) : ind(hlog.indentation, hlog.indentation + (i)) {}
+  explicit indenter(int i = 2) : ind(hlog.indentation, hlog.indentation + (i)) {}
   };
 
 struct indenter_finish : indenter {
-  indenter_finish(bool b = true): indenter(b ? 2:0) {}
+  explicit indenter_finish(bool b = true): indenter(b ? 2:0) {}
   ~indenter_finish() { if(hlog.indentation != ind.backup) println(hlog, "(done)"); }
   };
 
diff --git a/hyper_function.h b/hyper_function.h
index 5bb8a040..9904010a 100644
--- a/hyper_function.h
+++ b/hyper_function.h
@@ -19,10 +19,10 @@ template<class T, class R, class... Args>
 struct function_state : function_state_base<R, Args...> {
     T t_;
     explicit function_state(T t) : t_(std::move(t)) {}
-    R call(Args... args) const /*override*/ {
+    R call(Args... args) const override {
         return const_cast<T&>(t_)(static_cast<Args&&>(args)...);
     }
-    function_state_base<R, Args...> *clone() const /*override*/ {
+    function_state_base<R, Args...> *clone() const override {
         return new function_state(*this);
     }
 };
diff --git a/inforder.cpp b/inforder.cpp
index 4abe524f..a32094d2 100644
--- a/inforder.cpp
+++ b/inforder.cpp
@@ -21,7 +21,7 @@ EX namespace inforder {
 
   struct hrmap_inforder : hrmap_hyperbolic {
 
-    heptagon *create_step(heptagon *h, int direction) {
+    heptagon *create_step(heptagon *h, int direction) override {
       int deg = h->type;
       if(mixed()) deg = 7 - deg;
       auto h1 = init_heptagon(deg);
@@ -51,4 +51,4 @@ EX namespace inforder {
   EX }
 
 
-}
\ No newline at end of file
+}
diff --git a/kite.cpp b/kite.cpp
index 0f3dc6da..14d1531c 100644
--- a/kite.cpp
+++ b/kite.cpp
@@ -339,7 +339,7 @@ struct hrmap_kite : hrmap {
     return gm * where;
     }
 
-  virtual int wall_offset(cell *c) {
+  int wall_offset(cell *c) override {
     if(WDIM == 3)
       return kite::getshape(c->master) == kite::pKite ? 10 : 0;
     else
@@ -426,4 +426,4 @@ auto hooksw = addHook(hooks_swapdim, 100, [] { if(kite::in() && currentmap) kite
 #endif
 }}
 
-   
\ No newline at end of file
+   
diff --git a/pattern2.cpp b/pattern2.cpp
index efd83536..ae257c6d 100644
--- a/pattern2.cpp
+++ b/pattern2.cpp
@@ -664,10 +664,10 @@ EX namespace patterns {
       si.reflect = false;
       }
     else {
-      int ids = 0, tids = 0, td = 0;
+      int ids = 0, td = 0;
       for(int i=0; i<S3; i++) {
         int d = c->move(2*i)->master->fieldval;
-        ids |= (1<<d); tids += d;
+        ids |= (1<<d);
         }
       for(int i=0; i<S3; i++) {
         int d = c->move(2*i)->master->fieldval;
diff --git a/quotient.cpp b/quotient.cpp
index d4020bc7..4a7428d4 100644
--- a/quotient.cpp
+++ b/quotient.cpp
@@ -64,16 +64,16 @@ struct hrmap_quotient : hrmap_standard {
   
   void build();
   
-  hrmap_quotient() {
+  explicit hrmap_quotient() {
     generate_connections();    
     build();
     }
 
-  hrmap_quotient(const vector<int>& con) : connections(con) {
+  explicit hrmap_quotient(const vector<int>& con) : connections(con) {
     build();
     }
 
-  heptagon *getOrigin() { return allh[0]; }
+  heptagon *getOrigin() override { return allh[0]; }
 
   ~hrmap_quotient() {
     for(int i=0; i<isize(allh); i++) {
@@ -82,7 +82,7 @@ struct hrmap_quotient : hrmap_standard {
       }
     }
   
-  vector<cell*>& allcells() { return celllist; }
+  vector<cell*>& allcells() override { return celllist; }
   };
 #endif
   
diff --git a/reg3.cpp b/reg3.cpp
index ddcc2559..37859474 100644
--- a/reg3.cpp
+++ b/reg3.cpp
@@ -649,7 +649,7 @@ EX namespace reg3 {
     int h_id;
     /** transition matrix to that heptagon */
     transmatrix T;
-    /** the sequence of moves we need to make to get there */;
+    /** the sequence of moves we need to make to get there */
     vector<int> move_sequence;
     };
   
@@ -680,7 +680,7 @@ EX namespace reg3 {
       return cgi.subshapes[id].vertices_only_local;
       }
 
-    transmatrix master_relative(cell *c, bool get_inverse) {
+    transmatrix master_relative(cell *c, bool get_inverse) override {
       int id = local_id.at(c).second;
       auto& ss = cgi.subshapes[id];
       return get_inverse ? ss.from_cellcenter : ss.to_cellcenter;
@@ -689,11 +689,11 @@ EX namespace reg3 {
     void make_subconnections();
     
     int wall_offset(cell *c) override;
-    int shvid(cell *c) { return local_id.at(c).second; }
+    int shvid(cell *c) override { return local_id.at(c).second; }
     
-    virtual transmatrix ray_iadj(cell *c, int i) override;
+    transmatrix ray_iadj(cell *c, int i) override;
 
-    const vector<bool>& adjacent_dirs(cell *c, int i) { 
+    const vector<bool>& adjacent_dirs(cell *c, int i) override {
       int id = local_id.at(c).second;
       return cgi.subshapes[id].dirs_adjacent[i];
       }
@@ -1490,7 +1490,7 @@ EX namespace reg3 {
       return cgi.vertices_only;
       }
 
-    const vector<bool>& adjacent_dirs(cell *c, int i) { 
+    const vector<bool>& adjacent_dirs(cell *c, int i) override {
       return cgi.dirs_adjacent[i];
       }
 
@@ -1582,7 +1582,7 @@ EX namespace reg3 {
       clearfrom(allh[0]);
       }    
 
-    virtual struct transmatrix relative_matrix(heptagon *h2, heptagon *h1, const hyperpoint& hint) override {
+    struct transmatrix relative_matrix(heptagon *h2, heptagon *h1, const hyperpoint& hint) override {
       return iso_inverse(locations[h1->fieldval]) * locations[h2->fieldval];
       }
 
@@ -1901,13 +1901,13 @@ EX namespace reg3 {
       return relative_matrix_via_masters(c2, c1, hint);
       }
     
-    transmatrix master_relative(cell *c, bool get_inverse) {
+    transmatrix master_relative(cell *c, bool get_inverse) override {
       if(PURE) return Id;
       int aid = cell_id.at(c);
       return quotient_map->master_relative(quotient_map->acells[aid], get_inverse);
       }
 
-    int shvid(cell *c) {
+    int shvid(cell *c) override {
       if(PURE) return 0;
       if(!cell_id.count(c)) return quotient_map->shvid(c);
       int aid = cell_id.at(c);
@@ -1963,14 +1963,14 @@ EX namespace reg3 {
       c->c.connect(d, c1, ac->c.spin(d), false);
       }
 
-    virtual transmatrix ray_iadj(cell *c, int i) {
+    transmatrix ray_iadj(cell *c, int i) override {
       if(PURE) return iadj(c, i);
       if(!cell_id.count(c)) return quotient_map->ray_iadj(c, i); /* necessary because ray samples are from quotient_map */
       int aid = cell_id.at(c);
       return quotient_map->ray_iadj(quotient_map->acells[aid], i);
       }
 
-    const vector<bool>& adjacent_dirs(cell *c, int i) { 
+    const vector<bool>& adjacent_dirs(cell *c, int i) override { 
       if(PURE) return cgi.dirs_adjacent[i];
       int aid = cell_id.at(c);
       return quotient_map->adjacent_dirs(quotient_map->acells[aid], i);
diff --git a/sky.cpp b/sky.cpp
index 80f6897a..ea7f8c50 100644
--- a/sky.cpp
+++ b/sky.cpp
@@ -24,11 +24,11 @@ struct sky_item {
 
 struct dqi_sky : drawqueueitem {
   vector<sky_item> sky;
-  void draw();
-  virtual color_t outline_group() { return 3; }
+  void draw() override;
+  color_t outline_group() override { return 3; }
   // singleton
-  dqi_sky() { hr::sky = this; }
-  ~dqi_sky() { hr::sky = NULL; }
+  explicit dqi_sky() { hr::sky = this; }
+  ~dqi_sky() override { hr::sky = NULL; }
   };
   
 EX struct dqi_sky *sky;
diff --git a/sphere.cpp b/sphere.cpp
index 8d254ec6..7ed5a9c1 100644
--- a/sphere.cpp
+++ b/sphere.cpp
@@ -139,14 +139,14 @@ struct hrmap_spherical : hrmap_standard {
     #endif
     }
 
-  heptagon *getOrigin() { return dodecahedron[0]; }
+  heptagon *getOrigin() override { return dodecahedron[0]; }
 
   ~hrmap_spherical() {
     for(int i=0; i<spherecells(); i++) clearHexes(dodecahedron[i]);
     for(int i=0; i<spherecells(); i++) tailored_delete(dodecahedron[i]);
     }    
 
-  void verify() {
+  void verify() override {
     for(int i=0; i<spherecells(); i++) for(int k=0; k<S7; k++) {
       heptspin hs(dodecahedron[i], k, false);
       heptspin hs2 = hs + wstep + (S7-1) + wstep + (S7-1) + wstep + (S7-1);
@@ -172,7 +172,7 @@ struct hrmap_spherical : hrmap_standard {
     return Id;
     }
   
-  transmatrix relative_matrix(cell *c2, cell *c1, const hyperpoint& hint) {
+  transmatrix relative_matrix(cell *c2, cell *c1, const hyperpoint& hint) override {
     transmatrix T = iso_inverse(get_where(c1)) * get_where(c2);
     if(elliptic) fixelliptic(T);
     return T;