Fixing states 5 and 10 to ensure clock-wise walk.

radixalgorithm/marchingsquares.i.hh

@@ -97,8 +97,6 @@ std::vector<std::pair<int, int>> MarchingSquares<data_type>::march(
     // of rows and columns to allow for traveling the boundaries
     if (column >= 0 && column <= mColumns && row >= 0 && row <= mRows)
     {
-      radix_tagged_line("(" << row << ", " << column
-                            << ") =" << int(next_step));
       out.push_back({row, column});
     }
 
@@ -206,10 +204,7 @@ void MarchingSquares<data_type>::step(size_t r, size_t c)
       next_step = StepDirection::Left;
       break;
     case 2:
-      if (prev_step == StepDirection::Left)
       next_step = StepDirection::Up;
-      else
-        next_step = StepDirection::Right;
       break;
     case 3:
       next_step = StepDirection::Left;
@@ -218,57 +213,54 @@ void MarchingSquares<data_type>::step(size_t r, size_t c)
       next_step = StepDirection::Right;
       break;
     case 5:
-      next_step = StepDirection::Up;
-      break;
-    case 6:
       if (prev_step == StepDirection::Down)
-        next_step = StepDirection::Down;
+        next_step = StepDirection::Right;
       else
+        next_step = StepDirection::Left;
+      break;
+    case 6:
       next_step = StepDirection::Up;
       break;
     case 7:
-      if (prev_step == StepDirection::Up)
       next_step = StepDirection::Left;
-      else
-        next_step = StepDirection::Down;
       break;
     case 8:
       next_step = StepDirection::Down;
       break;
     case 9:
-      if (prev_step == StepDirection::Down)
       next_step = StepDirection::Down;
-      else
-        next_step = StepDirection::Up;
       break;
     case 10:
+      if (prev_step == StepDirection::Left)
         next_step = StepDirection::Down;
+      else
+        next_step = StepDirection::Up;
       break;
     case 11:
-      if (prev_step == StepDirection::Left)
       next_step = StepDirection::Down;
-      else
-        next_step = StepDirection::Right;
       break;
     case 12:
       next_step = StepDirection::Right;
       break;
     case 13:
-      if (prev_step == StepDirection::Down)
       next_step = StepDirection::Right;
-      else
-        next_step == StepDirection::Up;
       break;
     case 14:
-      if (prev_step == StepDirection::Down)
-        next_step = StepDirection::Left;
-      else
       next_step = StepDirection::Up;
       break;
     default:
       next_step = StepDirection::None;
       break;
   }
+
+  radix_tagged_line(
+      "(" << r << ", " << c << ") =" << state << " "
+          << ((next_step == StepDirection::Up)
+                  ? "Up"
+                  : ((next_step == StepDirection::Down)
+                         ? "Down"
+                         : (next_step == StepDirection::Left) ? "Left"
+                                                              : "Right")));
 }
 
 }  // namespace radix