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, 27 insertions, 2 deletions

diff --git a/source/blender/editors/space_sequencer/sequencer_add.c b/source/blender/editors/space_sequencer/sequencer_add.c
index 37dfcdbc765..71433a6978a 100644
--- a/source/blender/editors/space_sequencer/sequencer_add.c
+++ b/source/blender/editors/space_sequencer/sequencer_add.c
@@ -81,9 +81,18 @@ typedef struct SequencerAddData {
 #define SEQPROP_ENDFRAME (1 << 1)
 #define SEQPROP_NOPATHS (1 << 2)
 #define SEQPROP_NOCHAN (1 << 3)
+#define SEQPROP_FIT_METHOD (1 << 4)
 
 #define SELECT 1
 
+static const EnumPropertyItem scale_fit_methods[] = {
+    {SEQ_SCALE_TO_FIT, "FIT", 0, "Scale to Fit", "Scale image to fit within the canvas"},
+    {SEQ_SCALE_TO_FILL, "FILL", 0, "Scale to Fill", "Scale image to completely fill the canvas"},
+    {SEQ_STRETCH_TO_FILL, "STRETCH", 0, "Stretch to Fill", "Stretch image to fill the canvas"},
+    {SEQ_USE_ORIGINAL_SIZE, "ORIGINAL", 0, "Use Original Size", "Keep image at its original size"},
+    {0, NULL, 0, NULL, NULL},
+};
+
 static void sequencer_generic_props__internal(wmOperatorType *ot, int flag)
 {
   PropertyRNA *prop;
@@ -123,6 +132,15 @@ static void sequencer_generic_props__internal(wmOperatorType *ot, int flag)
   prop = RNA_def_boolean(
       ot->srna, "overlap", 0, "Allow Overlap", "Don't correct overlap on new sequence strips");
   RNA_def_property_flag(prop, PROP_HIDDEN);
+
+  if (flag & SEQPROP_FIT_METHOD) {
+    ot->prop = RNA_def_enum(ot->srna,
+                            "fit_method",
+                            scale_fit_methods,
+                            SEQ_SCALE_TO_FIT,
+                            "Fit Method",
+                            "Scale fit method");
+  }
 }
 
 static void sequencer_generic_invoke_path__internal(bContext *C,
@@ -206,6 +224,8 @@ static void seq_load_operator_info(SeqLoadInfo *seq_load, bContext *C, wmOperato
   seq_load->end_frame = seq_load->start_frame;
   seq_load->channel = RNA_int_get(op->ptr, "channel");
   seq_load->len = 1;
+  seq_load->fit_method = RNA_enum_get(op->ptr, "fit_method");
+  SEQ_tool_settings_fit_method_set(CTX_data_scene(C), seq_load->fit_method);
 
   if ((prop = RNA_struct_find_property(op->ptr, "filepath"))) {
     /* Full path, file is set by the caller. */
@@ -659,6 +679,7 @@ static int sequencer_add_movie_strip_invoke(bContext *C,
   if (ed && ed->seqbasep && ed->seqbasep->first) {
     RNA_boolean_set(op->ptr, "use_framerate", false);
   }
+  RNA_enum_set(op->ptr, "fit_method", SEQ_tool_settings_fit_method_get(scene));
 
   /* This is for drag and drop. */
   if ((RNA_struct_property_is_set(op->ptr, "files") && RNA_collection_length(op->ptr, "files")) ||
@@ -725,7 +746,7 @@ void SEQUENCER_OT_movie_strip_add(struct wmOperatorType *ot)
                                      WM_FILESEL_SHOW_PROPS | WM_FILESEL_DIRECTORY,
                                  FILE_DEFAULTDISPLAY,
                                  FILE_SORT_DEFAULT);
-  sequencer_generic_props__internal(ot, SEQPROP_STARTFRAME);
+  sequencer_generic_props__internal(ot, SEQPROP_STARTFRAME | SEQPROP_FIT_METHOD);
   RNA_def_boolean(ot->srna, "sound", true, "Sound", "Load sound with the movie");
   RNA_def_boolean(ot->srna,
                   "use_framerate",
@@ -928,6 +949,9 @@ static int sequencer_add_image_strip_invoke(bContext *C,
   PropertyRNA *prop;
   Scene *scene = CTX_data_scene(C);
 
+  const SequencerToolSettings *tool_settings = scene->toolsettings->sequencer_tool_settings;
+  RNA_enum_set(op->ptr, "fit_method", tool_settings->fit_method);
+
   /* Name set already by drag and drop. */
   if (RNA_struct_property_is_set(op->ptr, "files") && RNA_collection_length(op->ptr, "files")) {
     sequencer_generic_invoke_xy__internal(
@@ -972,7 +996,8 @@ void SEQUENCER_OT_image_strip_add(struct wmOperatorType *ot)
                                      WM_FILESEL_SHOW_PROPS | WM_FILESEL_DIRECTORY,
                                  FILE_DEFAULTDISPLAY,
                                  FILE_SORT_DEFAULT);
-  sequencer_generic_props__internal(ot, SEQPROP_STARTFRAME | SEQPROP_ENDFRAME);
+  sequencer_generic_props__internal(ot,
+                                    SEQPROP_STARTFRAME | SEQPROP_ENDFRAME | SEQPROP_FIT_METHOD);
 
   RNA_def_boolean(ot->srna,
                   "use_placeholders",