VSE: Make time operations self-contained

This patch makes it possible to manipulate strips without need to use
update functions to recalculate effect and meta strips.

Prior to this change function `SEQ_time_update_sequence` had to be used
to update mainly effects and meta strips. This was implemented in a way
that relied on sorted list of strips, which can't always be done and in
rare cases this approach failed.

In case of meta strips, `seqbase` had to be passed and compared with
"active" one to determine whether meta strip should be updated or not.
This is especially weak system that is prone to bugs when functions are
used by python API functions.

Finally, other strip types had startdisp` and `enddisp` fields updated
by this function and a lot of code relied on these fields even if strip
start, length and offsets are available. This is completely
unnecessary.

Implemented changes:
All effects and meta strips are updated when strip handles are moved or
strip is translated, without need to call any update function.

Function `SEQ_time_update_sequence` has been split to
`SEQ_time_update_meta_strip_range` and
`seq_time_update_effects_strip_range`. These functions should be only
used within sequencer module code. Meta update is used for versioning,
which is only reason for it not being declared internally.

Sequence fields `startdisp` and `enddisp` are now only used for
effects to store strip start and end points. These fields should be
used only internally within sequencer module code.
Use function `SEQ_time_*_handle_frame_get` to get strip start and end
points.

To update effects and meta strips with reasonable performance, cache
for "parent" meta strip and attached effects is added to
`SequenceLookup` cache, so it shares invalidation mechanisms.
All caches are populated during single iteration.

There should be no functional changes.

Differential Revision: https://developer.blender.org/D14990

1 files changed, 40 insertions, 29 deletions

diff --git a/source/blender/editors/space_sequencer/sequencer_select.c b/source/blender/editors/space_sequencer/sequencer_select.c
index 074be0fd120..f237fbc0a12 100644
--- a/source/blender/editors/space_sequencer/sequencer_select.c
+++ b/source/blender/editors/space_sequencer/sequencer_select.c
@@ -116,13 +116,13 @@ static void select_active_side(ListBase *seqbase, int sel_side, int channel, int
     if (channel == seq->machine) {
       switch (sel_side) {
         case SEQ_SIDE_LEFT:
-          if (frame > (seq->startdisp)) {
+          if (frame > (SEQ_time_left_handle_frame_get(seq))) {
             seq->flag &= ~(SEQ_RIGHTSEL | SEQ_LEFTSEL);
             seq->flag |= SELECT;
           }
           break;
         case SEQ_SIDE_RIGHT:
-          if (frame < (seq->startdisp)) {
+          if (frame < (SEQ_time_left_handle_frame_get(seq))) {
             seq->flag &= ~(SEQ_RIGHTSEL | SEQ_LEFTSEL);
             seq->flag |= SELECT;
           }
@@ -152,13 +152,13 @@ static void select_active_side_range(ListBase *seqbase,
       }
       switch (sel_side) {
         case SEQ_SIDE_LEFT:
-          if (frame > (seq->startdisp)) {
+          if (frame > (SEQ_time_left_handle_frame_get(seq))) {
             seq->flag &= ~(SEQ_RIGHTSEL | SEQ_LEFTSEL);
             seq->flag |= SELECT;
           }
           break;
         case SEQ_SIDE_RIGHT:
-          if (frame < (seq->startdisp)) {
+          if (frame < (SEQ_time_left_handle_frame_get(seq))) {
             seq->flag &= ~(SEQ_RIGHTSEL | SEQ_LEFTSEL);
             seq->flag |= SELECT;
           }
@@ -179,8 +179,8 @@ static void select_linked_time(ListBase *seqbase, Sequence *seq_link)
 
   for (seq = seqbase->first; seq; seq = seq->next) {
     if (seq_link->machine != seq->machine) {
-      int left_match = (seq->startdisp == seq_link->startdisp) ? 1 : 0;
-      int right_match = (seq->enddisp == seq_link->enddisp) ? 1 : 0;
+      int left_match = (SEQ_time_left_handle_frame_get(seq) == seq_link->startdisp) ? 1 : 0;
+      int right_match = (SEQ_time_right_handle_frame_get(seq) == seq_link->enddisp) ? 1 : 0;
 
       if (left_match && right_match) {
         /* Direct match, copy the selection settings. */
@@ -247,8 +247,8 @@ void ED_sequencer_select_sequence_single(Scene *scene, Sequence *seq, bool desel
 
 void seq_rectf(Sequence *seq, rctf *rect)
 {
-  rect->xmin = seq->startdisp;
-  rect->xmax = seq->enddisp;
+  rect->xmin = SEQ_time_left_handle_frame_get(seq);
+  rect->xmax = SEQ_time_right_handle_frame_get(seq);
   rect->ymin = seq->machine + SEQ_STRIP_OFSBOTTOM;
   rect->ymax = seq->machine + SEQ_STRIP_OFSTOP;
 }
@@ -273,12 +273,12 @@ Sequence *find_neighboring_sequence(Scene *scene, Sequence *test, int lr, int se
          (sel == 0 && (seq->flag & SELECT) == 0))) {
       switch (lr) {
         case SEQ_SIDE_LEFT:
-          if (test->startdisp == (seq->enddisp)) {
+          if (SEQ_time_left_handle_frame_get(test) == (SEQ_time_right_handle_frame_get(seq))) {
             return seq;
           }
           break;
         case SEQ_SIDE_RIGHT:
-          if (test->enddisp == (seq->startdisp)) {
+          if (SEQ_time_right_handle_frame_get(test) == (SEQ_time_left_handle_frame_get(seq))) {
             return seq;
           }
           break;
@@ -311,13 +311,18 @@ Sequence *find_nearest_seq(Scene *scene, View2D *v2d, int *hand, const int mval[
   while (seq) {
     if (seq->machine == (int)y) {
       /* Check for both normal strips, and strips that have been flipped horizontally. */
-      if (((seq->startdisp < seq->enddisp) && (seq->startdisp <= x && seq->enddisp >= x)) ||
-          ((seq->startdisp > seq->enddisp) && (seq->startdisp >= x && seq->enddisp <= x))) {
+      if (((SEQ_time_left_handle_frame_get(seq) < SEQ_time_right_handle_frame_get(seq)) &&
+           (SEQ_time_left_handle_frame_get(seq) <= x &&
+            SEQ_time_right_handle_frame_get(seq) >= x)) ||
+          ((SEQ_time_left_handle_frame_get(seq) > SEQ_time_right_handle_frame_get(seq)) &&
+           (SEQ_time_left_handle_frame_get(seq) >= x &&
+            SEQ_time_right_handle_frame_get(seq) <= x))) {
         if (SEQ_transform_sequence_can_be_translated(seq)) {
 
           /* Clamp handles to defined size in pixel space. */
           handsize = 2.0f * sequence_handle_size_get_clamped(seq, pixelx);
-          displen = (float)abs(seq->startdisp - seq->enddisp);
+          displen = (float)abs(SEQ_time_left_handle_frame_get(seq) -
+                               SEQ_time_right_handle_frame_get(seq));
 
           /* Don't even try to grab the handles of small strips. */
           if (displen / pixelx > 16) {
@@ -332,10 +337,10 @@ Sequence *find_nearest_seq(Scene *scene, View2D *v2d, int *hand, const int mval[
               CLAMP(handsize, 7 * pixelx, 30 * pixelx);
             }
 
-            if (handsize + seq->startdisp >= x) {
+            if (handsize + SEQ_time_left_handle_frame_get(seq) >= x) {
               *hand = SEQ_SIDE_LEFT;
             }
-            else if (-handsize + seq->enddisp <= x) {
+            else if (-handsize + SEQ_time_right_handle_frame_get(seq) <= x) {
               *hand = SEQ_SIDE_RIGHT;
             }
           }
@@ -578,8 +583,8 @@ static void sequencer_select_side_of_frame(const bContext *C,
 
   const float x = UI_view2d_region_to_view_x(v2d, mval[0]);
   LISTBASE_FOREACH (Sequence *, seq_iter, SEQ_active_seqbase_get(ed)) {
-    if (((x < CFRA) && (seq_iter->enddisp <= CFRA)) ||
-        ((x >= CFRA) && (seq_iter->startdisp >= CFRA))) {
+    if (((x < CFRA) && (SEQ_time_right_handle_frame_get(seq_iter) <= CFRA)) ||
+        ((x >= CFRA) && (SEQ_time_left_handle_frame_get(seq_iter) >= CFRA))) {
       /* Select left or right. */
       seq_iter->flag |= SELECT;
       recurs_sel_seq(seq_iter);
@@ -634,7 +639,8 @@ static void sequencer_select_linked_handle(const bContext *C,
         case SEQ_SIDE_LEFT:
           if ((seq->flag & SEQ_LEFTSEL) && (neighbor->flag & SEQ_RIGHTSEL)) {
             seq->flag |= SELECT;
-            select_active_side(ed->seqbasep, SEQ_SIDE_LEFT, seq->machine, seq->startdisp);
+            select_active_side(
+                ed->seqbasep, SEQ_SIDE_LEFT, seq->machine, SEQ_time_left_handle_frame_get(seq));
           }
           else {
             seq->flag |= SELECT;
@@ -647,7 +653,8 @@ static void sequencer_select_linked_handle(const bContext *C,
         case SEQ_SIDE_RIGHT:
           if ((seq->flag & SEQ_RIGHTSEL) && (neighbor->flag & SEQ_LEFTSEL)) {
             seq->flag |= SELECT;
-            select_active_side(ed->seqbasep, SEQ_SIDE_RIGHT, seq->machine, seq->startdisp);
+            select_active_side(
+                ed->seqbasep, SEQ_SIDE_RIGHT, seq->machine, SEQ_time_left_handle_frame_get(seq));
           }
           else {
             seq->flag |= SELECT;
@@ -661,7 +668,8 @@ static void sequencer_select_linked_handle(const bContext *C,
     }
     else {
 
-      select_active_side(ed->seqbasep, sel_side, seq->machine, seq->startdisp);
+      select_active_side(
+          ed->seqbasep, sel_side, seq->machine, SEQ_time_left_handle_frame_get(seq));
     }
   }
 }
@@ -1428,10 +1436,10 @@ static int sequencer_select_side_of_frame_exec(bContext *C, wmOperator *op)
     bool test = false;
     switch (side) {
       case -1:
-        test = (timeline_frame >= seq->enddisp);
+        test = (timeline_frame >= SEQ_time_right_handle_frame_get(seq));
         break;
       case 1:
-        test = (timeline_frame <= seq->startdisp);
+        test = (timeline_frame <= SEQ_time_left_handle_frame_get(seq));
         break;
       case 2:
         test = SEQ_time_strip_intersects_frame(seq, timeline_frame);
@@ -1505,10 +1513,10 @@ static int sequencer_select_side_exec(bContext *C, wmOperator *op)
     if (seq->flag & SELECT) {
       selected = true;
       if (sel_side == SEQ_SIDE_LEFT) {
-        *frame_limit_p = max_ii(*frame_limit_p, seq->startdisp);
+        *frame_limit_p = max_ii(*frame_limit_p, SEQ_time_left_handle_frame_get(seq));
       }
       else {
-        *frame_limit_p = min_ii(*frame_limit_p, seq->startdisp);
+        *frame_limit_p = min_ii(*frame_limit_p, SEQ_time_left_handle_frame_get(seq));
       }
     }
   }
@@ -1648,7 +1656,7 @@ static int sequencer_box_select_exec(bContext *C, wmOperator *op)
         float handsize = sequence_handle_size_get_clamped(seq, pixelx);
 
         /* Right handle. */
-        if (rectf.xmax > (seq->enddisp - handsize)) {
+        if (rectf.xmax > (SEQ_time_right_handle_frame_get(seq) - handsize)) {
           if (select) {
             seq->flag |= SELECT | SEQ_RIGHTSEL;
           }
@@ -1661,7 +1669,7 @@ static int sequencer_box_select_exec(bContext *C, wmOperator *op)
           }
         }
         /* Left handle. */
-        if (rectf.xmin < (seq->startdisp + handsize)) {
+        if (rectf.xmin < (SEQ_time_left_handle_frame_get(seq) + handsize)) {
           if (select) {
             seq->flag |= SELECT | SEQ_LEFTSEL;
           }
@@ -1953,7 +1961,8 @@ static bool select_grouped_time_overlap(SeqCollection *strips,
 
   Sequence *seq;
   SEQ_ITERATOR_FOREACH (seq, strips) {
-    if (seq->startdisp < actseq->enddisp && seq->enddisp > actseq->startdisp) {
+    if (SEQ_time_left_handle_frame_get(seq) < SEQ_time_right_handle_frame_get(actseq) &&
+        SEQ_time_right_handle_frame_get(seq) > SEQ_time_left_handle_frame_get(actseq)) {
       seq->flag |= SELECT;
       changed = true;
     }
@@ -1971,8 +1980,10 @@ static void query_lower_channel_strips(Sequence *seq_reference,
     if (seq_test->machine > seq_reference->machine) {
       continue; /* Not lower channel. */
     }
-    if (seq_test->enddisp <= seq_reference->startdisp ||
-        seq_test->startdisp >= seq_reference->enddisp) {
+    if (SEQ_time_right_handle_frame_get(seq_test) <=
+            SEQ_time_left_handle_frame_get(seq_reference) ||
+        SEQ_time_left_handle_frame_get(seq_test) >=
+            SEQ_time_right_handle_frame_get(seq_reference)) {
       continue; /* Not intersecting in time. */
     }
     SEQ_collection_append_strip(seq_test, collection);