VSE: Use edge panning

Add edge panning feature to transform operator. It works in same way as
in node editor, but Y axis is limited by usable range up to 128
channels.

Reviewed By: Severin

Differential Revision: https://developer.blender.org/D14310

5 files changed, 83 insertions, 10 deletions

diff --git a/release/scripts/presets/keyconfig/keymap_data/blender_default.py b/release/scripts/presets/keyconfig/keymap_data/blender_default.py
index 262d341e885..27556922f5e 100644
--- a/release/scripts/presets/keyconfig/keymap_data/blender_default.py
+++ b/release/scripts/presets/keyconfig/keymap_data/blender_default.py
@@ -2893,10 +2893,12 @@ def km_sequencer(params):
         ("sequencer.slip", {"type": 'S', "value": 'PRESS'}, None),
         ("wm.context_set_int", {"type": 'O', "value": 'PRESS'},
          {"properties": [("data_path", 'scene.sequence_editor.overlay_frame'), ("value", 0)]}),
-        ("transform.seq_slide", {"type": 'G', "value": 'PRESS'}, None),
-        ("transform.seq_slide", {"type": params.select_mouse, "value": 'CLICK_DRAG'}, None),
+        ("transform.seq_slide", {"type": 'G', "value": 'PRESS'},
+         {"properties": [("view2d_edge_pan", True)]}),
+        ("transform.seq_slide", {"type": params.select_mouse, "value": 'CLICK_DRAG'},
+         {"properties": [("view2d_edge_pan", True)]}),
         ("transform.transform", {"type": 'E', "value": 'PRESS'},
-         {"properties": [("mode", 'TIME_EXTEND')]}),
+         {"properties": [("mode", 'TIME_EXTEND'), ("view2d_edge_pan", True)]}),
         ("marker.add", {"type": 'M', "value": 'PRESS'}, None),
         ("marker.rename", {"type": 'M', "value": 'PRESS', "ctrl": True}, None),
         ("sequencer.select_side_of_frame", {"type": 'LEFT_BRACKET', "value": 'PRESS'},
diff --git a/source/blender/editors/include/UI_view2d.h b/source/blender/editors/include/UI_view2d.h
index 4282465c0ca..56b0bd04a71 100644
--- a/source/blender/editors/include/UI_view2d.h
+++ b/source/blender/editors/include/UI_view2d.h
@@ -447,6 +447,8 @@ typedef struct View2DEdgePanData {
   struct ARegion *region;
   /** View2d we're operating in. */
   struct View2D *v2d;
+    /* Limit maximum pannable area */
+  struct rctf limit;
 
   /** Panning should only start once being in the inside rect once (e.g. adding nodes can happen
    * outside). */
@@ -492,6 +494,12 @@ void UI_view2d_edge_pan_init(struct bContext *C,
                              float delay,
                              float zoom_influence);
 
+/**
+ * Set area which can be panned
+ */
+void UI_view2d_edge_pan_set_limits(
+    struct View2DEdgePanData *vpd, float xmin, float xmax, float ymin, float ymax);
+
 void UI_view2d_edge_pan_reset(struct View2DEdgePanData *vpd);
 
 /**
diff --git a/source/blender/editors/interface/view2d_edge_pan.cc b/source/blender/editors/interface/view2d_edge_pan.cc
index ab1672ae8f6..82959d96043 100644
--- a/source/blender/editors/interface/view2d_edge_pan.cc
+++ b/source/blender/editors/interface/view2d_edge_pan.cc
@@ -67,6 +67,7 @@ void UI_view2d_edge_pan_init(bContext *C,
   vpd->area = CTX_wm_area(C);
   vpd->region = CTX_wm_region(C);
   vpd->v2d = &vpd->region->v2d;
+  BLI_rctf_init(&vpd->limit, -FLT_MAX, FLT_MAX, -FLT_MAX, FLT_MAX);
 
   BLI_assert(speed_ramp > 0.0f);
   vpd->inside_pad = inside_pad;
@@ -87,6 +88,12 @@ void UI_view2d_edge_pan_init(bContext *C,
   UI_view2d_edge_pan_reset(vpd);
 }
 
+void UI_view2d_edge_pan_set_limits(
+    View2DEdgePanData *vpd, float xmin, float xmax, float ymin, float ymax)
+{
+  BLI_rctf_init(&vpd->limit, xmin, xmax, ymin, ymax);
+}
+
 void UI_view2d_edge_pan_reset(View2DEdgePanData *vpd)
 {
   vpd->edge_pan_start_time_x = 0.0;
@@ -220,20 +227,23 @@ void UI_view2d_edge_pan_apply(bContext *C, View2DEdgePanData *vpd, const int xy[
     vpd->enabled = true;
   }
 
+  rctf *cur = &vpd->v2d->cur;
+  rctf *limit = &vpd->limit;
+
   int pan_dir_x = 0;
   int pan_dir_y = 0;
   if (vpd->enabled && ((vpd->outside_pad == 0) || BLI_rcti_isect_pt_v(&outside_rect, xy))) {
     /* Find whether the mouse is beyond X and Y edges. */
-    if (xy[0] > inside_rect.xmax) {
+    if (xy[0] > inside_rect.xmax && cur->xmax < limit->xmax) {
       pan_dir_x = 1;
     }
-    else if (xy[0] < inside_rect.xmin) {
+    else if (xy[0] < inside_rect.xmin && cur->xmin > limit->xmin) {
       pan_dir_x = -1;
     }
-    if (xy[1] > inside_rect.ymax) {
+    if (xy[1] > inside_rect.ymax && cur->ymax < limit->ymax) {
       pan_dir_y = 1;
     }
-    else if (xy[1] < inside_rect.ymin) {
+    else if (xy[1] < inside_rect.ymin && cur->ymin > limit->ymin) {
       pan_dir_y = -1;
     }
   }
diff --git a/source/blender/editors/transform/transform_convert_sequencer.c b/source/blender/editors/transform/transform_convert_sequencer.c
index b355b459c1e..16a96001fd2 100644
--- a/source/blender/editors/transform/transform_convert_sequencer.c
+++ b/source/blender/editors/transform/transform_convert_sequencer.c
@@ -35,6 +35,13 @@
 #include "transform.h"
 #include "transform_convert.h"
 
+#define SEQ_EDGE_PAN_INSIDE_PAD 2
+#define SEQ_EDGE_PAN_OUTSIDE_PAD 0 /* Disable clamping for panning, use whole screen. */
+#define SEQ_EDGE_PAN_SPEED_RAMP 1
+#define SEQ_EDGE_PAN_MAX_SPEED 4 /* In UI units per second, slower than default. */
+#define SEQ_EDGE_PAN_DELAY 1.0f
+#define SEQ_EDGE_PAN_ZOOM_INFLUENCE 0.5f
+
 /** Used for sequencer transform. */
 typedef struct TransDataSeq {
   struct Sequence *seq;
@@ -55,6 +62,10 @@ typedef struct TransSeq {
   TransDataSeq *tdseq;
   int selection_channel_range_min;
   int selection_channel_range_max;
+
+  /* Initial rect of the view2d, used for computing offset during edge panning */
+  rctf initial_v2d_cur;
+  View2DEdgePanData edge_pan;
 } TransSeq;
 
 /* -------------------------------------------------------------------- */
@@ -673,6 +684,18 @@ void createTransSeqData(TransInfo *t)
   td2d = tc->data_2d = MEM_callocN(tc->data_len * sizeof(TransData2D), "TransSeq TransData2D");
   ts->tdseq = tdsq = MEM_callocN(tc->data_len * sizeof(TransDataSeq), "TransSeq TransDataSeq");
 
+  /* Custom data to enable edge panning during transformation. */
+  UI_view2d_edge_pan_init(t->context,
+                          &ts->edge_pan,
+                          SEQ_EDGE_PAN_INSIDE_PAD,
+                          SEQ_EDGE_PAN_OUTSIDE_PAD,
+                          SEQ_EDGE_PAN_SPEED_RAMP,
+                          SEQ_EDGE_PAN_MAX_SPEED,
+                          SEQ_EDGE_PAN_DELAY,
+                          SEQ_EDGE_PAN_ZOOM_INFLUENCE);
+  UI_view2d_edge_pan_set_limits(&ts->edge_pan, -FLT_MAX, FLT_MAX, 1, MAXSEQ + 1);
+  ts->initial_v2d_cur = t->region->v2d.cur;
+
   /* loop 2: build transdata array */
   SeqToTransData_build(t, ed->seqbasep, td, td2d, tdsq);
 
@@ -710,8 +733,36 @@ BLI_INLINE void trans_update_seq(Scene *sce, Sequence *seq, int old_start, int s
   }
 }
 
+static void view2d_edge_pan_loc_compensate(TransInfo *t, float loc_in[2], float r_loc[2])
+{
+  TransSeq *ts = (TransSeq *)TRANS_DATA_CONTAINER_FIRST_SINGLE(t)->custom.type.data;
+
+  /* Initial and current view2D rects for additional transform due to view panning and zooming */
+  const rctf *rect_src = &ts->initial_v2d_cur;
+  const rctf *rect_dst = &t->region->v2d.cur;
+
+  copy_v2_v2(r_loc, loc_in);
+  /* Additional offset due to change in view2D rect. */
+  BLI_rctf_transform_pt_v(rect_dst, rect_src, r_loc, r_loc);
+}
+
 static void flushTransSeq(TransInfo *t)
 {
+  TransSeq *ts = (TransSeq *)TRANS_DATA_CONTAINER_FIRST_SINGLE(t)->custom.type.data;
+  if (t->options & CTX_VIEW2D_EDGE_PAN) {
+    if (t->state == TRANS_CANCEL) {
+      UI_view2d_edge_pan_cancel(t->context, &ts->edge_pan);
+    }
+    else {
+      /* Edge panning functions expect window coordinates, mval is relative to region */
+      const int xy[2] = {
+          t->region->winrct.xmin + t->mval[0],
+          t->region->winrct.ymin + t->mval[1],
+      };
+      UI_view2d_edge_pan_apply(t->context, &ts->edge_pan, xy);
+    }
+  }
+
   /* Editing null check already done */
   ListBase *seqbasep = seqbase_active_get(t);
 
@@ -727,7 +778,9 @@ static void flushTransSeq(TransInfo *t)
   for (a = 0, td = tc->data, td2d = tc->data_2d; a < tc->data_len; a++, td++, td2d++) {
     tdsq = (TransDataSeq *)td->extra;
     seq = tdsq->seq;
-    new_frame = round_fl_to_int(td2d->loc[0]);
+    float loc[2];
+    view2d_edge_pan_loc_compensate(t, td->loc, loc);
+    new_frame = round_fl_to_int(loc[0]);
 
     switch (tdsq->sel_flag) {
       case SELECT:
@@ -735,7 +788,7 @@ static void flushTransSeq(TransInfo *t)
           const int offset = new_frame - tdsq->start_offset - seq->start;
           SEQ_transform_translate_sequence(t->scene, seq, offset);
         }
-        seq->machine = round_fl_to_int(td2d->loc[1]);
+        seq->machine = round_fl_to_int(loc[1]);
         CLAMP(seq->machine, 1, MAXSEQ);
         break;
 
diff --git a/source/blender/editors/transform/transform_ops.c b/source/blender/editors/transform/transform_ops.c
index efbb7375af4..ec49cef4067 100644
--- a/source/blender/editors/transform/transform_ops.c
+++ b/source/blender/editors/transform/transform_ops.c
@@ -1255,7 +1255,7 @@ static void TRANSFORM_OT_seq_slide(struct wmOperatorType *ot)
 
   WM_operatortype_props_advanced_begin(ot);
 
-  Transform_Properties(ot, P_SNAP);
+  Transform_Properties(ot, P_SNAP | P_VIEW2D_EDGE_PAN);
 }
 
 static void TRANSFORM_OT_rotate_normal(struct wmOperatorType *ot)