Cleanup: Refactor marker area clamping

Switch from a single function with a lot of branching at its top level
to dedicated function calls with own documentation.

2 files changed, 64 insertions, 43 deletions

diff --git a/source/blender/blenkernel/BKE_tracking.h b/source/blender/blenkernel/BKE_tracking.h
index 1d4ff06703d..3f6d32e2f70 100644
--- a/source/blender/blenkernel/BKE_tracking.h
+++ b/source/blender/blenkernel/BKE_tracking.h
@@ -32,12 +32,6 @@ struct rcti;
  * Common types and constants.
  */
 
-enum {
-  CLAMP_PAT_POS = 2,
-  CLAMP_SEARCH_DIM = 3,
-  CLAMP_SEARCH_POS = 4,
-};
-
 typedef enum eTrackArea {
   TRACK_AREA_POINT = (1 << 0),
   TRACK_AREA_PAT = (1 << 1),
@@ -292,7 +286,35 @@ struct MovieTrackingMarker *BKE_tracking_marker_insert(struct MovieTrackingTrack
                                                        struct MovieTrackingMarker *marker);
 void BKE_tracking_marker_delete(struct MovieTrackingTrack *track, int framenr);
 
-void BKE_tracking_marker_clamp(struct MovieTrackingMarker *marker, int event);
+/**
+ * If the pattern area is outside of the search area its position will be modified in a way that it
+ * is within the pattern is within the search area.
+ *
+ * If the pattern area is already within the search area nothing happens.
+ *
+ * If the pattern area is bigger than the search area the behavior is undefined.
+ *
+ * Search area is never modified.
+ */
+void BKE_tracking_marker_clamp_pattern_position(struct MovieTrackingMarker *marker);
+
+/**
+ * If the search size is such that pattern area is (partially) outside of the search area make the
+ * search area bigger so that the pattern is within the search area.
+ *
+ * Pattern area is never modified.
+ */
+void BKE_tracking_marker_clamp_search_size(struct MovieTrackingMarker *marker);
+
+/**
+ * If the search position is such that pattern area is (partially) outside of the search area move
+ * the search area so that the pattern is within the search area.
+ *
+ * If the search area is smaller than the pattern the behavior is undefined.
+ *
+ * Pattern area is never modified.
+ */
+void BKE_tracking_marker_clamp_search_position(struct MovieTrackingMarker *marker);
 
 /**
  * Get marker closest to the given frame number.
diff --git a/source/blender/blenkernel/intern/tracking.c b/source/blender/blenkernel/intern/tracking.c
index 307e9eca8cb..f9d3a44e5cb 100644
--- a/source/blender/blenkernel/intern/tracking.c
+++ b/source/blender/blenkernel/intern/tracking.c
@@ -1367,53 +1367,52 @@ void BKE_tracking_marker_delete(MovieTrackingTrack *track, int framenr)
   }
 }
 
-void BKE_tracking_marker_clamp(MovieTrackingMarker *marker, int event)
+void BKE_tracking_marker_clamp_pattern_position(MovieTrackingMarker *marker)
 {
   float pat_min[2], pat_max[2];
-
   BKE_tracking_marker_pattern_minmax(marker, pat_min, pat_max);
 
-  if (event == CLAMP_PAT_POS) {
-    float dim[2];
-
-    sub_v2_v2v2(dim, pat_max, pat_min);
-
-    for (int a = 0; a < 2; a++) {
-      /* pattern shouldn't be moved outside of search */
-      if (pat_min[a] < marker->search_min[a]) {
-        for (int b = 0; b < 4; b++) {
-          marker->pattern_corners[b][a] += marker->search_min[a] - pat_min[a];
-        }
+  for (int a = 0; a < 2; a++) {
+    if (pat_min[a] < marker->search_min[a]) {
+      for (int b = 0; b < 4; b++) {
+        marker->pattern_corners[b][a] += marker->search_min[a] - pat_min[a];
       }
-      if (pat_max[a] > marker->search_max[a]) {
-        for (int b = 0; b < 4; b++) {
-          marker->pattern_corners[b][a] -= pat_max[a] - marker->search_max[a];
-        }
+    }
+    if (pat_max[a] > marker->search_max[a]) {
+      for (int b = 0; b < 4; b++) {
+        marker->pattern_corners[b][a] -= pat_max[a] - marker->search_max[a];
       }
     }
   }
-  else if (event == CLAMP_SEARCH_DIM) {
-    for (int a = 0; a < 2; a++) {
-      /* search shouldn't be resized smaller than pattern */
-      marker->search_min[a] = min_ff(pat_min[a], marker->search_min[a]);
-      marker->search_max[a] = max_ff(pat_max[a], marker->search_max[a]);
-    }
+}
+
+void BKE_tracking_marker_clamp_search_size(MovieTrackingMarker *marker)
+{
+  float pat_min[2], pat_max[2];
+  BKE_tracking_marker_pattern_minmax(marker, pat_min, pat_max);
+
+  for (int a = 0; a < 2; a++) {
+    marker->search_min[a] = min_ff(pat_min[a], marker->search_min[a]);
+    marker->search_max[a] = max_ff(pat_max[a], marker->search_max[a]);
   }
-  else if (event == CLAMP_SEARCH_POS) {
-    float dim[2];
+}
+
+void BKE_tracking_marker_clamp_search_position(MovieTrackingMarker *marker)
+{
+  float pat_min[2], pat_max[2];
+  BKE_tracking_marker_pattern_minmax(marker, pat_min, pat_max);
 
-    sub_v2_v2v2(dim, marker->search_max, marker->search_min);
+  float dim[2];
+  sub_v2_v2v2(dim, marker->search_max, marker->search_min);
 
-    for (int a = 0; a < 2; a++) {
-      /* search shouldn't be moved inside pattern */
-      if (marker->search_min[a] > pat_min[a]) {
-        marker->search_min[a] = pat_min[a];
-        marker->search_max[a] = marker->search_min[a] + dim[a];
-      }
-      if (marker->search_max[a] < pat_max[a]) {
-        marker->search_max[a] = pat_max[a];
-        marker->search_min[a] = marker->search_max[a] - dim[a];
-      }
+  for (int a = 0; a < 2; a++) {
+    if (marker->search_min[a] > pat_min[a]) {
+      marker->search_min[a] = pat_min[a];
+      marker->search_max[a] = marker->search_min[a] + dim[a];
+    }
+    if (marker->search_max[a] < pat_max[a]) {
+      marker->search_max[a] = pat_max[a];
+      marker->search_min[a] = marker->search_max[a] - dim[a];
     }
   }
 }