From 672d67859f5720e69bca3a97ec96a02362091c1a Mon Sep 17 00:00:00 2001
From: Stefan Weil <sw@weilnetz.de>
Date: Mon, 30 Sep 2019 21:33:15 +0200
Subject: [PATCH] mfoutline: Modernize code

- Use C++ enums
- Use strongly typed C++11 enum for DIRECTION and optimize struct MFEDGEPT
- Use float constant for MF_SCALE_FACTOR
- Replace macros by inline functions
- Fix documentation comment

This fixes several warnings from clang.

Signed-off-by: Stefan Weil <sw@weilnetz.de>
---
 src/classify/mfoutline.cpp |  7 +++--
 src/classify/mfoutline.h   | 62 +++++++++++++++++++++++---------------
 2 files changed, 42 insertions(+), 27 deletions(-)

diff --git a/src/classify/mfoutline.cpp b/src/classify/mfoutline.cpp
index 9cdef184..e506b294 100644
--- a/src/classify/mfoutline.cpp
+++ b/src/classify/mfoutline.cpp
@@ -63,7 +63,7 @@ MFOUTLINE ConvertOutline(TESSLINE *outline) {
     if (EdgePoint->pos.x != NextPoint->pos.x ||
         EdgePoint->pos.y != NextPoint->pos.y) {
       NewPoint = NewEdgePoint();
-      ClearMark(NewPoint);
+      NewPoint->ClearMark();
       NewPoint->Hidden = EdgePoint->IsHidden();
       NewPoint->Point.x = EdgePoint->pos.x;
       NewPoint->Point.y = EdgePoint->pos.y;
@@ -192,7 +192,7 @@ void MarkDirectionChanges(MFOUTLINE Outline) {
   Last = First;
   do {
     Current = NextDirectionChange (Last);
-    MarkPoint (PointAt (Current));
+    PointAt(Current)->MarkPoint();
     Last = Current;
   }
   while (Last != First);
@@ -303,7 +303,8 @@ void Classify::NormalizeOutlines(LIST Outlines,
  * starts at Start and ends at End.  Note that the previous
  * direction of End must also be changed to reflect the
  * change in direction of the point before it.
- * @param Start, End  defines segment of outline to be modified
+ * @param Start defines start of segment of outline to be modified
+ * @param End defines end of segment of outline to be modified
  * @param Direction new direction to assign to segment
  */
 void ChangeDirection(MFOUTLINE Start, MFOUTLINE End, DIRECTION Direction) {
diff --git a/src/classify/mfoutline.h b/src/classify/mfoutline.h
index 435408aa..2e14071e 100644
--- a/src/classify/mfoutline.h
+++ b/src/classify/mfoutline.h
@@ -26,12 +26,9 @@
 #include "oldlist.h"
 #include "params.h"
 
-#define NORMAL_X_HEIGHT (0.5)
-#define NORMAL_BASELINE (0.0)
-
 using MFOUTLINE = LIST;
 
-typedef enum {
+enum DIRECTION : uint8_t {
   north,
   south,
   east,
@@ -40,39 +37,56 @@ typedef enum {
   northwest,
   southeast,
   southwest
-} DIRECTION;
+};
+
+struct MFEDGEPT {
+  // Inline functions for manipulating micro-feature outline edge points.
+
+  void ClearMark() {
+    ExtremityMark = false;
+  }
+
+  void MarkPoint() {
+    ExtremityMark = true;
+  }
 
-typedef struct {
   FPOINT Point;
   float Slope;
-  unsigned Padding : 20;
-  bool Hidden : true;
-  bool ExtremityMark : true;
-  DIRECTION Direction : 4;
-  DIRECTION PreviousDirection : 4;
-} MFEDGEPT;
+  bool Hidden;
+  bool ExtremityMark;
+  DIRECTION Direction;
+  DIRECTION PreviousDirection;
+};
 
-typedef enum { outer, hole } OUTLINETYPE;
+enum OUTLINETYPE { outer, hole };
 
-typedef enum { baseline, character } NORM_METHOD;
+enum NORM_METHOD { baseline, character };
 
 /**----------------------------------------------------------------------------
           Macros
 ----------------------------------------------------------------------------**/
 #define AverageOf(A, B) (((A) + (B)) / 2)
 
-/* macro for computing the scale factor to use to normalize characters */
-#define MF_SCALE_FACTOR (NORMAL_X_HEIGHT / kBlnXHeight)
+// Constant for computing the scale factor to use to normalize characters.
+const float MF_SCALE_FACTOR = 0.5f / kBlnXHeight;
 
-/* macros for manipulating micro-feature outlines */
-#define DegenerateOutline(O) (((O) == NIL_LIST) || ((O) == list_rest(O)))
-#define PointAt(O) ((MFEDGEPT*)first_node(O))
-#define NextPointAfter(E) (list_rest(E))
-#define MakeOutlineCircular(O) (set_rest(last(O), (O)))
+// Inline functions for manipulating micro-feature outlines.
 
-/* macros for manipulating micro-feature outline edge points */
-#define ClearMark(P) ((P)->ExtremityMark = false)
-#define MarkPoint(P) ((P)->ExtremityMark = true)
+static inline bool DegenerateOutline(MFOUTLINE Outline) {
+  return (Outline == NIL_LIST) || (Outline == list_rest(Outline));
+}
+
+static inline MFEDGEPT* PointAt(MFOUTLINE Outline) {
+  return reinterpret_cast<MFEDGEPT*>first_node(Outline);
+}
+
+static inline MFOUTLINE NextPointAfter(MFOUTLINE Outline) {
+  return list_rest(Outline);
+}
+
+static inline void MakeOutlineCircular(MFOUTLINE Outline) {
+  set_rest(last(Outline), Outline);
+}
 
 /**----------------------------------------------------------------------------
           Public Function Prototypes