backed-map:: moved same_point_may_warn to backed-map.cpp

backed-map.cpp

@@ -114,6 +114,23 @@ void backed_map::rebase(heptagon*& backer, transmatrix& T) {
     }
   }
 
+EX ld worst_precision_error;
+
+#if HDR
+struct hr_precision_error : hr_exception { hr_precision_error() : hr_exception("precision error") {} };
+#endif
+
+/** check if a and b are the same, testing for equality. Throw an exception or warning if not sure */
+EX bool same_point_may_warn(hyperpoint a, hyperpoint b) {
+  ld d = hdist(a, b);
+  if(d > 1e-2) return false;
+  if(d > 1e-3) throw hr_precision_error();
+  if(d > 1e-6 && worst_precision_error <= 1e-6)
+    addMessage("warning: precision errors are building up!");
+  if(d > worst_precision_error) worst_precision_error = d;
+  return true;
+  }
+
 bool in_hpe = false;
 
 void backed_map::handle_precision_errors(heptagon *h) {