VSE: Improved Retiming system

Patch implements better way to control playback speed than it is
possible to do with speed effect. Speed factor property can be set in
Time panel.

There are 2 layers of control:

Option to retime movie to match scene FPS rate.
Custom speed factor to control playback rate.
Since playback rate is strip property, it is now possible to manipulate
strip as normal one even if it is retimed.

To facilitate manipulation, some functions need to consider speed factor
and apply necessary corrections to strip offset or strip start. These
corrections may need to be float numbers, so start and offsets must be
float as well.

Sound strips now use speed factor instead of pitch. This means, that
strips will change length to match usable length. In addition, it is
possible to group movie and sound strip and change speed of meta strip.

1 files changed, 42 insertions, 34 deletions

diff --git a/source/blender/editors/transform/transform_convert_sequencer.c b/source/blender/editors/transform/transform_convert_sequencer.c
index 226b0f84f14..849641fd320 100644
--- a/source/blender/editors/transform/transform_convert_sequencer.c
+++ b/source/blender/editors/transform/transform_convert_sequencer.c
@@ -91,8 +91,8 @@ static void SeqTransInfo(TransInfo *t, Sequence *seq, int *r_count, int *r_flag)
 
     /* *** Extend Transform *** */
     int cfra = CFRA;
-    int left = SEQ_time_left_handle_frame_get(seq);
-    int right = SEQ_time_right_handle_frame_get(seq);
+    int left = SEQ_time_left_handle_frame_get(scene, seq);
+    int right = SEQ_time_right_handle_frame_get(scene, seq);
 
     if (((seq->flag & SELECT) == 0 || SEQ_transform_is_locked(channels, seq))) {
       *r_count = 0;
@@ -163,8 +163,13 @@ static int SeqTransCount(TransInfo *t, ListBase *seqbase)
   return tot;
 }
 
-static TransData *SeqToTransData(
-    TransData *td, TransData2D *td2d, TransDataSeq *tdsq, Sequence *seq, int flag, int sel_flag)
+static TransData *SeqToTransData(Scene *scene,
+                                 TransData *td,
+                                 TransData2D *td2d,
+                                 TransDataSeq *tdsq,
+                                 Sequence *seq,
+                                 int flag,
+                                 int sel_flag)
 {
   int start_left;
 
@@ -173,16 +178,16 @@ static TransData *SeqToTransData(
       /* Use seq_tx_get_final_left() and an offset here
        * so transform has the left hand location of the strip.
        * tdsq->start_offset is used when flushing the tx data back */
-      start_left = SEQ_time_left_handle_frame_get(seq);
+      start_left = SEQ_time_left_handle_frame_get(scene, seq);
       td2d->loc[0] = start_left;
       tdsq->start_offset = start_left - seq->start; /* use to apply the original location */
       break;
     case SEQ_LEFTSEL:
-      start_left = SEQ_time_left_handle_frame_get(seq);
+      start_left = SEQ_time_left_handle_frame_get(scene, seq);
       td2d->loc[0] = start_left;
       break;
     case SEQ_RIGHTSEL:
-      td2d->loc[0] = SEQ_time_right_handle_frame_get(seq);
+      td2d->loc[0] = SEQ_time_right_handle_frame_get(scene, seq);
       break;
   }
 
@@ -227,6 +232,7 @@ static int SeqToTransData_build(
     TransInfo *t, ListBase *seqbase, TransData *td, TransData2D *td2d, TransDataSeq *tdsq)
 {
   Sequence *seq;
+  Scene *scene = t->scene;
   int count, flag;
   int tot = 0;
 
@@ -238,16 +244,16 @@ static int SeqToTransData_build(
     if (flag & SELECT) {
       if (flag & (SEQ_LEFTSEL | SEQ_RIGHTSEL)) {
         if (flag & SEQ_LEFTSEL) {
-          SeqToTransData(td++, td2d++, tdsq++, seq, flag, SEQ_LEFTSEL);
+          SeqToTransData(scene, td++, td2d++, tdsq++, seq, flag, SEQ_LEFTSEL);
           tot++;
         }
         if (flag & SEQ_RIGHTSEL) {
-          SeqToTransData(td++, td2d++, tdsq++, seq, flag, SEQ_RIGHTSEL);
+          SeqToTransData(scene, td++, td2d++, tdsq++, seq, flag, SEQ_RIGHTSEL);
           tot++;
         }
       }
       else {
-        SeqToTransData(td++, td2d++, tdsq++, seq, flag, SELECT);
+        SeqToTransData(scene, td++, td2d++, tdsq++, seq, flag, SELECT);
         tot++;
       }
     }
@@ -275,7 +281,7 @@ static void seq_transform_cancel(TransInfo *t, SeqCollection *transformed_strips
   SEQ_ITERATOR_FOREACH (seq, transformed_strips) {
     /* Handle pre-existing overlapping strips even when operator is canceled.
      * This is necessary for SEQUENCER_OT_duplicate_move macro for example. */
-    if (SEQ_transform_test_overlap(seqbase, seq)) {
+    if (SEQ_transform_test_overlap(t->scene, seqbase, seq)) {
       SEQ_transform_seqbase_shuffle(seqbase, seq, t->scene);
     }
   }
@@ -318,7 +324,8 @@ static void freeSeqData(TransInfo *t, TransDataContainer *tc, TransCustomData *c
   }
 
   SeqCollection *transformed_strips = seq_transform_collection_from_transdata(tc);
-  SEQ_collection_expand(seqbase_active_get(t), transformed_strips, SEQ_query_strip_effect_chain);
+  SEQ_collection_expand(
+      t->scene, seqbase_active_get(t), transformed_strips, SEQ_query_strip_effect_chain);
 
   Sequence *seq;
   SEQ_ITERATOR_FOREACH (seq, transformed_strips) {
@@ -363,11 +370,11 @@ typedef enum SeqInputSide {
   SEQ_INPUT_RIGHT = 1,
 } SeqInputSide;
 
-static Sequence *effect_input_get(Sequence *effect, SeqInputSide side)
+static Sequence *effect_input_get(const Scene *scene, Sequence *effect, SeqInputSide side)
 {
   Sequence *input = effect->seq1;
-  if (effect->seq2 && (SEQ_time_left_handle_frame_get(effect->seq2) -
-                       SEQ_time_left_handle_frame_get(effect->seq1)) *
+  if (effect->seq2 && (SEQ_time_left_handle_frame_get(scene, effect->seq2) -
+                       SEQ_time_left_handle_frame_get(scene, effect->seq1)) *
                               side >
                           0) {
     input = effect->seq2;
@@ -375,12 +382,12 @@ static Sequence *effect_input_get(Sequence *effect, SeqInputSide side)
   return input;
 }
 
-static Sequence *effect_base_input_get(Sequence *effect, SeqInputSide side)
+static Sequence *effect_base_input_get(const Scene *scene, Sequence *effect, SeqInputSide side)
 {
   Sequence *input = effect, *seq_iter = effect;
   while (seq_iter != NULL) {
     input = seq_iter;
-    seq_iter = effect_input_get(seq_iter, side);
+    seq_iter = effect_input_get(scene, seq_iter, side);
   }
   return input;
 }
@@ -400,7 +407,7 @@ static SeqCollection *query_time_dependent_strips_strips(TransInfo *t)
   SeqCollection *strips_no_handles = query_selected_strips_no_handles(seqbase);
   /* Selection is needed as reference for related strips. */
   SeqCollection *dependent = SEQ_collection_duplicate(strips_no_handles);
-  SEQ_collection_expand(seqbase, strips_no_handles, SEQ_query_strip_effect_chain);
+  SEQ_collection_expand(t->scene, seqbase, strips_no_handles, SEQ_query_strip_effect_chain);
   bool strip_added = true;
 
   while (strip_added) {
@@ -430,7 +437,7 @@ static SeqCollection *query_time_dependent_strips_strips(TransInfo *t)
    * With single input effect, it is less likely desirable to move animation. */
 
   SeqCollection *selected_strips = SEQ_query_selected_strips(seqbase);
-  SEQ_collection_expand(seqbase, selected_strips, SEQ_query_strip_effect_chain);
+  SEQ_collection_expand(t->scene, seqbase, selected_strips, SEQ_query_strip_effect_chain);
   Sequence *seq;
   SEQ_ITERATOR_FOREACH (seq, selected_strips) {
     /* Check only 2 input effects. */
@@ -439,8 +446,8 @@ static SeqCollection *query_time_dependent_strips_strips(TransInfo *t)
     }
 
     /* Find immediate base inputs(left and right side). */
-    Sequence *input_left = effect_base_input_get(seq, SEQ_INPUT_LEFT);
-    Sequence *input_right = effect_base_input_get(seq, SEQ_INPUT_RIGHT);
+    Sequence *input_left = effect_base_input_get(t->scene, seq, SEQ_INPUT_LEFT);
+    Sequence *input_right = effect_base_input_get(t->scene, seq, SEQ_INPUT_RIGHT);
 
     if ((input_left->flag & SEQ_RIGHTSEL) != 0 && (input_right->flag & SEQ_LEFTSEL) != 0) {
       SEQ_collection_append_strip(seq, dependent);
@@ -571,6 +578,8 @@ static void flushTransSeq(TransInfo *t)
   TransDataSeq *tdsq = NULL;
   Sequence *seq;
 
+  Scene *scene = t->scene;
+
   TransDataContainer *tc = TRANS_DATA_CONTAINER_FIRST_SINGLE(t);
 
   /* This is calculated for offsetting animation of effects that change position with inputs.
@@ -594,7 +603,7 @@ static void flushTransSeq(TransInfo *t)
       case SELECT: {
         if (SEQ_transform_sequence_can_be_translated(seq)) {
           offset = new_frame - tdsq->start_offset - seq->start;
-          SEQ_transform_translate_sequence(t->scene, seq, offset);
+          SEQ_transform_translate_sequence(scene, seq, offset);
           if (abs(offset) > abs(max_offset)) {
             max_offset = offset;
           }
@@ -604,24 +613,22 @@ static void flushTransSeq(TransInfo *t)
         break;
       }
       case SEQ_LEFTSEL: { /* No vertical transform. */
-        int old_startdisp = SEQ_time_left_handle_frame_get(seq);
+        int old_startdisp = SEQ_time_left_handle_frame_get(scene, seq);
         SEQ_time_left_handle_frame_set(t->scene, seq, new_frame);
-        SEQ_transform_handle_xlimits(
-            t->scene, seq, tdsq->flag & SEQ_LEFTSEL, tdsq->flag & SEQ_RIGHTSEL);
         SEQ_transform_fix_single_image_seq_offsets(t->scene, seq);
-        if (abs(SEQ_time_left_handle_frame_get(seq) - old_startdisp) > abs(max_offset)) {
-          max_offset = SEQ_time_left_handle_frame_get(seq) - old_startdisp;
+
+        if (abs(SEQ_time_left_handle_frame_get(scene, seq) - old_startdisp) > abs(max_offset)) {
+          max_offset = SEQ_time_left_handle_frame_get(scene, seq) - old_startdisp;
         }
         break;
       }
       case SEQ_RIGHTSEL: { /* No vertical transform. */
-        int old_enddisp = SEQ_time_right_handle_frame_get(seq);
+        int old_enddisp = SEQ_time_right_handle_frame_get(scene, seq);
         SEQ_time_right_handle_frame_set(t->scene, seq, new_frame);
-        SEQ_transform_handle_xlimits(
-            t->scene, seq, tdsq->flag & SEQ_LEFTSEL, tdsq->flag & SEQ_RIGHTSEL);
         SEQ_transform_fix_single_image_seq_offsets(t->scene, seq);
-        if (abs(SEQ_time_right_handle_frame_get(seq) - old_enddisp) > abs(max_offset)) {
-          max_offset = SEQ_time_right_handle_frame_get(seq) - old_enddisp;
+
+        if (abs(SEQ_time_right_handle_frame_get(scene, seq) - old_enddisp) > abs(max_offset)) {
+          max_offset = SEQ_time_right_handle_frame_get(scene, seq) - old_enddisp;
         }
         break;
       }
@@ -638,12 +645,13 @@ static void flushTransSeq(TransInfo *t)
   /* need to do the overlap check in a new loop otherwise adjacent strips
    * will not be updated and we'll get false positives */
   SeqCollection *transformed_strips = seq_transform_collection_from_transdata(tc);
-  SEQ_collection_expand(seqbase_active_get(t), transformed_strips, SEQ_query_strip_effect_chain);
+  SEQ_collection_expand(
+      t->scene, seqbase_active_get(t), transformed_strips, SEQ_query_strip_effect_chain);
 
   SEQ_ITERATOR_FOREACH (seq, transformed_strips) {
     /* test overlap, displays red outline */
     seq->flag &= ~SEQ_OVERLAP;
-    if (SEQ_transform_test_overlap(seqbasep, seq)) {
+    if (SEQ_transform_test_overlap(scene, seqbasep, seq)) {
       seq->flag |= SEQ_OVERLAP;
     }
   }