Tracking: Re-duplicate logic used to count and initialize data

Allows to easily implement more comprehensive checks about which
markers get added to the transformation context.

No user measurable changes are expected, purely house-keeping to
ease an upcoming development.

1 files changed, 75 insertions, 56 deletions

diff --git a/source/blender/editors/transform/transform_convert_tracking.c b/source/blender/editors/transform/transform_convert_tracking.c
index 59dd5766f45..24e6d6a64f7 100644
--- a/source/blender/editors/transform/transform_convert_tracking.c
+++ b/source/blender/editors/transform/transform_convert_tracking.c
@@ -74,6 +74,14 @@ enum transDataTracking_Mode {
  * \{ */
 
 typedef struct TransformInitContext {
+  SpaceClip *space_clip;
+  TransDataContainer *tc;
+
+  /* MOTE: There pointers will be nullptr during counting step.
+   * This means, that the transformation data initialization functions are to increment
+   * `tc->data_len` instead of filling in the transformation data when these pointers are nullptr.
+   * For simplicitly, check the `current.td` against nullptr.
+   * Do not `tc->data_len` when filling in the transformation data. */
   struct {
     TransData *td;
     TransData2D *td2d;
@@ -94,6 +102,11 @@ static void markerToTransDataInit(TransformInitContext *init_context,
   TransData2D *td2d = init_context->current.td2d;
   TransDataTracking *tdt = init_context->current.tdt;
 
+  if (td == NULL) {
+    init_context->tc->data_len++;
+    return;
+  }
+
   int anchor = area == TRACK_AREA_POINT && off;
 
   tdt->flag = marker->flag;
@@ -216,7 +229,23 @@ static void trackToTransData(TransformInitContext *init_context,
                           aspect);
   }
 
-  marker->flag &= ~(MARKER_DISABLED | MARKER_TRACKED);
+  if (init_context->current.td != NULL) {
+    marker->flag &= ~(MARKER_DISABLED | MARKER_TRACKED);
+  }
+}
+
+static void trackToTransDataIfNeeded(TransformInitContext *init_context,
+                                     const int framenr,
+                                     MovieTrackingTrack *track,
+                                     const float aspect[2])
+{
+  if (!TRACK_VIEW_SELECTED(init_context->space_clip, track)) {
+    return;
+  }
+  if (track->flag & TRACK_LOCKED) {
+    return;
+  }
+  trackToTransData(init_context, framenr, track, aspect);
 }
 
 static void planeMarkerToTransDataInit(TransformInitContext *init_context,
@@ -229,6 +258,11 @@ static void planeMarkerToTransDataInit(TransformInitContext *init_context,
   TransData2D *td2d = init_context->current.td2d;
   TransDataTracking *tdt = init_context->current.tdt;
 
+  if (td == NULL) {
+    init_context->tc->data_len++;
+    return;
+  }
+
   tdt->flag = plane_marker->flag;
   tdt->mode = transDataTracking_ModePlaneTracks;
   tdt->plane_track = plane_track;
@@ -273,7 +307,20 @@ static void planeTrackToTransData(TransformInitContext *init_context,
         init_context, plane_track, plane_marker, plane_marker->corners[i], aspect);
   }
 
-  plane_marker->flag &= ~PLANE_MARKER_TRACKED;
+  if (init_context->current.td != NULL) {
+    plane_marker->flag &= ~PLANE_MARKER_TRACKED;
+  }
+}
+
+static void planeTrackToTransDataIfNeeded(TransformInitContext *init_context,
+                                          const int framenr,
+                                          MovieTrackingPlaneTrack *plane_track,
+                                          const float aspect[2])
+{
+  if (!PLANE_TRACK_VIEW_SELECTED(plane_track)) {
+    return;
+  }
+  planeTrackToTransData(init_context, framenr, plane_track, aspect);
 }
 
 static void transDataTrackingFree(TransInfo *UNUSED(t),
@@ -293,80 +340,52 @@ static void transDataTrackingFree(TransInfo *UNUSED(t),
 
 static void createTransTrackingTracksData(bContext *C, TransInfo *t)
 {
-  TransData *td;
-  TransData2D *td2d;
-  SpaceClip *sc = CTX_wm_space_clip(C);
-  MovieClip *clip = ED_space_clip_get_clip(sc);
-  ListBase *tracksbase = BKE_tracking_get_active_tracks(&clip->tracking);
-  ListBase *plane_tracks_base = BKE_tracking_get_active_plane_tracks(&clip->tracking);
-  MovieTrackingTrack *track;
-  MovieTrackingPlaneTrack *plane_track;
-  TransDataTracking *tdt;
-  int framenr = ED_space_clip_get_clip_frame_number(sc);
+  SpaceClip *space_clip = CTX_wm_space_clip(C);
+  MovieClip *clip = ED_space_clip_get_clip(space_clip);
+  const ListBase *tracksbase = BKE_tracking_get_active_tracks(&clip->tracking);
+  const ListBase *plane_tracks_base = BKE_tracking_get_active_plane_tracks(&clip->tracking);
+  const int framenr = ED_space_clip_get_clip_frame_number(space_clip);
 
   TransDataContainer *tc = TRANS_DATA_CONTAINER_FIRST_SINGLE(t);
 
-  /* count */
-  tc->data_len = 0;
-
-  track = tracksbase->first;
-  while (track) {
-    if (TRACK_VIEW_SELECTED(sc, track) && (track->flag & TRACK_LOCKED) == 0) {
-      tc->data_len++; /* offset */
+  TransformInitContext init_context = {NULL};
+  init_context.space_clip = space_clip;
+  init_context.tc = tc;
 
-      if (track->flag & SELECT) {
-        tc->data_len++;
-      }
+  /* Count required tranformation data. */
 
-      if (track->pat_flag & SELECT) {
-        tc->data_len += 4;
-      }
-
-      if (track->search_flag & SELECT) {
-        tc->data_len += 2;
-      }
-    }
+  tc->data_len = 0;
 
-    track = track->next;
+  LISTBASE_FOREACH (MovieTrackingTrack *, track, tracksbase) {
+    trackToTransDataIfNeeded(&init_context, framenr, track, t->aspect);
   }
 
-  for (plane_track = plane_tracks_base->first; plane_track; plane_track = plane_track->next) {
-    if (PLANE_TRACK_VIEW_SELECTED(plane_track)) {
-      tc->data_len += 4;
-    }
+  LISTBASE_FOREACH (MovieTrackingPlaneTrack *, plane_track, plane_tracks_base) {
+    planeTrackToTransDataIfNeeded(&init_context, framenr, plane_track, t->aspect);
   }
 
   if (tc->data_len == 0) {
     return;
   }
 
-  td = tc->data = MEM_callocN(tc->data_len * sizeof(TransData), "TransTracking TransData");
-  td2d = tc->data_2d = MEM_callocN(tc->data_len * sizeof(TransData2D),
-                                   "TransTracking TransData2D");
-  tdt = tc->custom.type.data = MEM_callocN(tc->data_len * sizeof(TransDataTracking),
-                                           "TransTracking TransDataTracking");
-
+  tc->data = MEM_callocN(tc->data_len * sizeof(TransData), "TransTracking TransData");
+  tc->data_2d = MEM_callocN(tc->data_len * sizeof(TransData2D), "TransTracking TransData2D");
+  tc->custom.type.data = MEM_callocN(tc->data_len * sizeof(TransDataTracking),
+                                     "TransTracking TransDataTracking");
   tc->custom.type.free_cb = transDataTrackingFree;
 
-  TransformInitContext init_context;
-  init_context.current.td = td;
-  init_context.current.td2d = td2d;
-  init_context.current.tdt = tdt;
+  init_context.current.td = tc->data;
+  init_context.current.td2d = tc->data_2d;
+  init_context.current.tdt = tc->custom.type.data;
 
-  /* create actual data */
-  track = tracksbase->first;
-  while (track) {
-    if (TRACK_VIEW_SELECTED(sc, track) && (track->flag & TRACK_LOCKED) == 0) {
-      trackToTransData(&init_context, framenr, track, t->aspect);
-    }
+  /* Create actual transformation data. */
 
-    track = track->next;
+  LISTBASE_FOREACH (MovieTrackingTrack *, track, tracksbase) {
+    trackToTransDataIfNeeded(&init_context, framenr, track, t->aspect);
   }
 
-  for (plane_track = plane_tracks_base->first; plane_track; plane_track = plane_track->next) {
-    if (PLANE_TRACK_VIEW_SELECTED(plane_track)) {
-      planeTrackToTransData(&init_context, framenr, plane_track, t->aspect);
-    }
+  LISTBASE_FOREACH (MovieTrackingPlaneTrack *, plane_track, plane_tracks_base) {
+    planeTrackToTransDataIfNeeded(&init_context, framenr, plane_track, t->aspect);
   }
 }