VSE: Improve motion-picture workflow

This commit resolves problem introduced in e1665c3d3190 - it was
difficult to import media at their original resolution.
This is done by using original resolution as reference for scale.

All crop and strip transform values and their animation is converted
form old files.

To make both workflows easy to use, sequencer tool settings have been
created with preset for preffered scaling method. This setting is in
sequencer timeline header and add image or movie strip operator
properties.

Two new operators have been added:
`sequencer.strip_transform_fit` operator with 3 options: Scale To Fit,
Scale to Fill and Stretch To Fill.
Operator can fail if strip image or video is not loaded currently, this
case should be either sanitized or data loaded on demand.

`sequencer.strip_transform_clear` operator with 4 options:
Clear position, scale, rotation and all (previous 3 options combined).

Reviewed By: sergey, fsiddi

Differential Revision: https://developer.blender.org/D9582

1 files changed, 145 insertions, 0 deletions

diff --git a/source/blender/editors/space_sequencer/sequencer_edit.c b/source/blender/editors/space_sequencer/sequencer_edit.c
index 1e3529a9607..ddc9ba2e0f6 100644
--- a/source/blender/editors/space_sequencer/sequencer_edit.c
+++ b/source/blender/editors/space_sequencer/sequencer_edit.c
@@ -3414,3 +3414,148 @@ Sequence *find_nearest_seq(Scene *scene, View2D *v2d, int *hand, const int mval[
 }
 
 /** \} */
+
+/* -------------------------------------------------------------------- */
+/** \name Clear Strip Transform Operator
+ * \{ */
+
+enum {
+  STRIP_TRANSFORM_POSITION,
+  STRIP_TRANSFORM_SCALE,
+  STRIP_TRANSFORM_ROTATION,
+  STRIP_TRANSFORM_ALL,
+};
+
+static const EnumPropertyItem transform_reset_properties[] = {
+    {STRIP_TRANSFORM_POSITION, "POSITION", 0, "Position", "Reset strip transform location"},
+    {STRIP_TRANSFORM_SCALE, "SCALE", 0, "Scale", "Reset strip transform scale"},
+    {STRIP_TRANSFORM_ROTATION, "ROTATION", 0, "Rotation", "Reset strip transform rotation"},
+    {STRIP_TRANSFORM_ALL, "ALL", 0, "All", "Reset strip transform location, scale and rotation"},
+    {0, NULL, 0, NULL, NULL},
+};
+
+static int sequencer_strip_transform_clear_exec(bContext *C, wmOperator *op)
+{
+  Scene *scene = CTX_data_scene(C);
+  const Editing *ed = BKE_sequencer_editing_get(scene, false);
+  Sequence *seq;
+  const int property = RNA_enum_get(op->ptr, "property");
+
+  for (seq = ed->seqbasep->first; seq; seq = seq->next) {
+    if (seq->flag & SELECT && seq->type != SEQ_TYPE_SOUND_RAM) {
+      StripTransform *transform = seq->strip->transform;
+      switch (property) {
+        case STRIP_TRANSFORM_POSITION:
+          transform->xofs = 0;
+          transform->yofs = 0;
+          break;
+        case STRIP_TRANSFORM_SCALE:
+          transform->scale_x = 1.0f;
+          transform->scale_y = 1.0f;
+          break;
+        case STRIP_TRANSFORM_ROTATION:
+          transform->rotation = 0.0f;
+          break;
+        case STRIP_TRANSFORM_ALL:
+          transform->xofs = 0;
+          transform->yofs = 0;
+          transform->scale_x = 1.0f;
+          transform->scale_y = 1.0f;
+          transform->rotation = 0.0f;
+          break;
+      }
+      BKE_sequence_invalidate_cache_preprocessed(scene, seq);
+    }
+  }
+
+  WM_event_add_notifier(C, NC_SCENE | ND_SEQUENCER, scene);
+  return OPERATOR_FINISHED;
+}
+
+void SEQUENCER_OT_strip_transform_clear(struct wmOperatorType *ot)
+{
+  /* Identifiers. */
+  ot->name = "Clear Strip Transform";
+  ot->idname = "SEQUENCER_OT_strip_transform_clear";
+  ot->description = "Reset image transformation to default value";
+
+  /* Api callbacks. */
+  ot->exec = sequencer_strip_transform_clear_exec;
+  ot->poll = sequencer_edit_poll;
+
+  /* Flags. */
+  ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
+
+  ot->prop = RNA_def_enum(ot->srna,
+                          "property",
+                          transform_reset_properties,
+                          STRIP_TRANSFORM_ALL,
+                          "Property",
+                          "Strip transform property to be reset");
+}
+
+/** \} */
+
+/* -------------------------------------------------------------------- */
+/** \name Transform Set Fit Operator
+ * \{ */
+
+static const EnumPropertyItem scale_fit_methods[] = {
+    {SEQ_SCALE_TO_FIT, "FIT", 0, "Scale to Fit", "Scale image so fits in preview"},
+    {SEQ_SCALE_TO_FILL, "FILL", 0, "Scale to Fill", "Scale image so it fills preview completely"},
+    {SEQ_STRETCH_TO_FILL, "STRETCH", 0, "Stretch to Fill", "Stretch image so it fills preview"},
+    {0, NULL, 0, NULL, NULL},
+};
+
+static int sequencer_strip_transform_fit_exec(bContext *C, wmOperator *op)
+{
+  Scene *scene = CTX_data_scene(C);
+  const Editing *ed = BKE_sequencer_editing_get(scene, false);
+  Sequence *seq;
+  const eSeqImageFitMethod fit_method = RNA_enum_get(op->ptr, "fit_method");
+
+  for (seq = ed->seqbasep->first; seq; seq = seq->next) {
+    if (seq->flag & SELECT && seq->type != SEQ_TYPE_SOUND_RAM) {
+      const int timeline_frame = CFRA;
+      StripElem *strip_elem = SEQ_render_give_stripelem(seq, timeline_frame);
+
+      if (strip_elem == NULL) {
+        continue;
+      }
+
+      SEQ_set_scale_to_fit(seq,
+                           strip_elem->orig_width,
+                           strip_elem->orig_height,
+                           scene->r.xsch,
+                           scene->r.ysch,
+                           fit_method);
+      BKE_sequence_invalidate_cache_preprocessed(scene, seq);
+    }
+  }
+
+  WM_event_add_notifier(C, NC_SCENE | ND_SEQUENCER, scene);
+  return OPERATOR_FINISHED;
+}
+
+void SEQUENCER_OT_strip_transform_fit(struct wmOperatorType *ot)
+{
+  /* Identifiers. */
+  ot->name = "Strip Transform Set Fit";
+  ot->idname = "SEQUENCER_OT_strip_transform_fit";
+
+  /* Api callbacks. */
+  ot->exec = sequencer_strip_transform_fit_exec;
+  ot->poll = sequencer_edit_poll;
+
+  /* Flags. */
+  ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
+
+  ot->prop = RNA_def_enum(ot->srna,
+                          "fit_method",
+                          scale_fit_methods,
+                          SEQ_SCALE_TO_FIT,
+                          "Fit Method",
+                          "Scale fit fit_method");
+}
+
+/** \} */