VSE: Improved Snapping

Change snapping behavior to snap strip edges when they are close to snap point.
Default behavior is, that each transformed strip is snapped to any other strip.

Implement snapping controls in sequencer tool settings. These controls include:

 - Snapping on/off
 - Ability to snap to playhead and strip hold offset points
 - Filter snap points by excluding sound or muted strips
 - Control snapping distance

Snapping controls are placed in timeline header similar to 3D viewport

Reviewed By: mano-wii

Differential Revision: https://developer.blender.org/D11646

1 files changed, 4 insertions, 58 deletions

diff --git a/source/blender/editors/transform/transform_convert_sequencer.c b/source/blender/editors/transform/transform_convert_sequencer.c
index 2cb0e3c8589..51914004e70 100644
--- a/source/blender/editors/transform/transform_convert_sequencer.c
+++ b/source/blender/editors/transform/transform_convert_sequencer.c
@@ -63,9 +63,6 @@ typedef struct TransDataSeq {
  */
 typedef struct TransSeq {
   TransDataSeq *tdseq;
-  int min;
-  int max;
-  bool snap_left;
   int selection_channel_range_min;
   int selection_channel_range_max;
 } TransSeq;
@@ -252,42 +249,6 @@ static int SeqToTransData_build(
   return tot;
 }
 
-static void SeqTransDataBounds(TransInfo *t, ListBase *seqbase, TransSeq *ts)
-{
-  Sequence *seq;
-  int count, flag;
-  int max = INT32_MIN, min = INT32_MAX;
-
-  for (seq = seqbase->first; seq; seq = seq->next) {
-
-    /* just to get the flag since there are corner cases where this isn't totally obvious */
-    SeqTransInfo(t, seq, &count, &flag);
-
-    /* use 'flag' which is derived from seq->flag but modified for special cases */
-    if (flag & SELECT) {
-      if (flag & (SEQ_LEFTSEL | SEQ_RIGHTSEL)) {
-        if (flag & SEQ_LEFTSEL) {
-          min = min_ii(seq->startdisp, min);
-          max = max_ii(seq->startdisp, max);
-        }
-        if (flag & SEQ_RIGHTSEL) {
-          min = min_ii(seq->enddisp, min);
-          max = max_ii(seq->enddisp, max);
-        }
-      }
-      else {
-        min = min_ii(seq->startdisp, min);
-        max = max_ii(seq->enddisp, max);
-      }
-    }
-  }
-
-  if (ts) {
-    ts->max = max;
-    ts->min = min;
-  }
-}
-
 static void free_transform_custom_data(TransCustomData *custom_data)
 {
   if ((custom_data->data != NULL) && custom_data->use_free) {
@@ -544,15 +505,6 @@ void createTransSeqData(TransInfo *t)
 
   /* loop 2: build transdata array */
   SeqToTransData_build(t, ed->seqbasep, td, td2d, tdsq);
-  SeqTransDataBounds(t, ed->seqbasep, ts);
-
-  if (t->flag & T_MODAL) {
-    /* set the snap mode based on how close the mouse is at the end/start points */
-    int xmouse = (int)UI_view2d_region_to_view_x((View2D *)t->view, t->mouse.imval[0]);
-    if (abs(xmouse - ts->max) > abs(xmouse - ts->min)) {
-      ts->snap_left = true;
-    }
-  }
 
   ts->selection_channel_range_min = MAXSEQ + 1;
   LISTBASE_FOREACH (Sequence *, seq, SEQ_active_seqbase_get(ed)) {
@@ -719,25 +671,19 @@ void special_aftertrans_update__sequencer(bContext *UNUSED(C), TransInfo *t)
   }
 }
 
-void transform_convert_sequencer_channel_clamp(TransInfo *t)
+void transform_convert_sequencer_channel_clamp(TransInfo *t, float r_val[2])
 {
   const TransSeq *ts = (TransSeq *)TRANS_DATA_CONTAINER_FIRST_SINGLE(t)->custom.type.data;
-  const int channel_offset = round_fl_to_int(t->values[1]);
+  const int channel_offset = round_fl_to_int(r_val[1]);
   const int min_channel_after_transform = ts->selection_channel_range_min + channel_offset;
   const int max_channel_after_transform = ts->selection_channel_range_max + channel_offset;
 
   if (max_channel_after_transform > MAXSEQ) {
-    t->values[1] -= max_channel_after_transform - MAXSEQ;
+    r_val[1] -= max_channel_after_transform - MAXSEQ;
   }
   if (min_channel_after_transform < 1) {
-    t->values[1] -= min_channel_after_transform - 1;
+    r_val[1] -= min_channel_after_transform - 1;
   }
 }
 
-int transform_convert_sequencer_get_snap_bound(TransInfo *t)
-{
-  TransSeq *ts = TRANS_DATA_CONTAINER_FIRST_SINGLE(t)->custom.type.data;
-  return ts->snap_left ? ts->min : ts->max;
-}
-
 /** \} */