Add a reverse frames menu option in the right click frame menu

Is enabled only when multiple frames are selected.

Translations/Translations.pot

@@ -1716,6 +1716,10 @@ msgstr ""
 msgid "Frame properties"
 msgstr ""
 
+#. Found on the popup menu that appears when a user right-clicks on a frame button. When clicked, the order of the selected frames is being reversed.
+msgid "Reverse Frames"
+msgstr ""
+
 msgid "Layer"
 msgstr ""
 

src/Classes/Project.gd

@@ -672,17 +672,7 @@ func add_frames(new_frames: Array, indices: Array) -> void:  # indices should be
 		# Add frame
 		frames.insert(indices[i], new_frames[i])
 		Global.animation_timeline.project_frame_added(indices[i])
-	# Update the frames and frame buttons:
+	_update_frame_ui()
-	for f in frames.size():
-		Global.frame_hbox.get_child(f).frame = f
-		Global.frame_hbox.get_child(f).text = str(f + 1)
-	# Update the cel buttons:
-	for l in layers.size():
-		var cel_hbox: HBoxContainer = Global.cel_vbox.get_child(layers.size() - 1 - l)
-		for f in frames.size():
-			cel_hbox.get_child(f).frame = f
-			cel_hbox.get_child(f).button_setup()
-	_set_timeline_first_and_last_frames()
 
 
 func remove_frames(indices: Array) -> void:  # indices should be in ascending order
@@ -701,17 +691,7 @@ func remove_frames(indices: Array) -> void:  # indices should be in ascending or
 		# Remove frame
 		frames.remove(indices[i] - i)
 		Global.animation_timeline.project_frame_removed(indices[i] - i)
-	# Update the frames and frame buttons:
+	_update_frame_ui()
-	for f in frames.size():
-		Global.frame_hbox.get_child(f).frame = f
-		Global.frame_hbox.get_child(f).text = str(f + 1)
-	# Update the cel buttons:
-	for l in layers.size():
-		var cel_hbox: HBoxContainer = Global.cel_vbox.get_child(layers.size() - 1 - l)
-		for f in frames.size():
-			cel_hbox.get_child(f).frame = f
-			cel_hbox.get_child(f).button_setup()
-	_set_timeline_first_and_last_frames()
 
 
 func move_frame(from_index: int, to_index: int) -> void:
@@ -722,17 +702,7 @@ func move_frame(from_index: int, to_index: int) -> void:
 	Global.animation_timeline.project_frame_removed(from_index)
 	frames.insert(to_index, frame)
 	Global.animation_timeline.project_frame_added(to_index)
-	# Update the frames and frame buttons:
+	_update_frame_ui()
-	for f in frames.size():
-		Global.frame_hbox.get_child(f).frame = f
-		Global.frame_hbox.get_child(f).text = str(f + 1)
-	# Update the cel buttons:
-	for l in layers.size():
-		var cel_hbox: HBoxContainer = Global.cel_vbox.get_child(layers.size() - 1 - l)
-		for f in frames.size():
-			cel_hbox.get_child(f).frame = f
-			cel_hbox.get_child(f).button_setup()
-	_set_timeline_first_and_last_frames()
 
 
 func swap_frame(a_index: int, b_index: int) -> void:
@@ -748,6 +718,22 @@ func swap_frame(a_index: int, b_index: int) -> void:
 	_set_timeline_first_and_last_frames()
 
 
+func reverse_frames(frame_indices: Array) -> void:
+	Global.canvas.selection.transform_content_confirm()
+# warning-ignore:integer_division
+	for i in frame_indices.size() / 2:
+		var index: int = frame_indices[i]
+		var reverse_index: int = frame_indices[-i - 1]
+		var temp: Frame = frames[index]
+		frames[index] = frames[reverse_index]
+		frames[reverse_index] = temp
+		Global.animation_timeline.project_frame_removed(index)
+		Global.animation_timeline.project_frame_added(index)
+		Global.animation_timeline.project_frame_removed(reverse_index)
+		Global.animation_timeline.project_frame_added(reverse_index)
+	_set_timeline_first_and_last_frames()
+
+
 func add_layers(new_layers: Array, indices: Array, cels: Array) -> void:  # cels is 2d Array of cels
 	Global.canvas.selection.transform_content_confirm()
 	selected_cels.clear()
@@ -899,3 +885,16 @@ func swap_cel(a_frame: int, a_layer: int, b_frame: int, b_layer: int) -> void:
 	Global.animation_timeline.project_cel_added(a_frame, a_layer)
 	Global.animation_timeline.project_cel_removed(b_frame, b_layer)
 	Global.animation_timeline.project_cel_added(b_frame, b_layer)
+
+
+func _update_frame_ui() -> void:
+	for f in frames.size():  # Update the frames and frame buttons
+		Global.frame_hbox.get_child(f).frame = f
+		Global.frame_hbox.get_child(f).text = str(f + 1)
+
+	for l in layers.size():  # Update the cel buttons
+		var cel_hbox: HBoxContainer = Global.cel_vbox.get_child(layers.size() - 1 - l)
+		for f in frames.size():
+			cel_hbox.get_child(f).frame = f
+			cel_hbox.get_child(f).button_setup()
+	_set_timeline_first_and_last_frames()

src/UI/Timeline/AnimationTimeline.gd

@@ -389,6 +389,22 @@ func _on_MoveRight_pressed() -> void:
 	Global.frame_hbox.get_child(frame).change_frame_order(1)
 
 
+func reverse_frames() -> void:
+	var project = Global.current_project
+	var indices := []
+	for cel in Global.current_project.selected_cels:
+		var f: int = cel[0]
+		if not f in indices:
+			indices.append(f)
+	indices.sort()
+	project.undo_redo.create_action("Change Frame Order")
+	project.undo_redo.add_do_method(project, "reverse_frames", indices)
+	project.undo_redo.add_undo_method(project, "reverse_frames", indices)
+	project.undo_redo.add_undo_method(Global, "undo_or_redo", true)
+	project.undo_redo.add_do_method(Global, "undo_or_redo", false)
+	project.undo_redo.commit_action()
+
+
 func _on_OnionSkinning_pressed() -> void:
 	Global.onion_skinning = !Global.onion_skinning
 	Global.canvas.refresh_onion()

src/UI/Timeline/FrameButton.gd

@@ -1,5 +1,7 @@
 extends Button
 
+enum { REMOVE, CLONE, MOVE_LEFT, MOVE_RIGHT, PROPERTIES, REVERSE }
+
 var frame := 0
 
 onready var popup_menu: PopupMenu = $PopupMenu
@@ -15,7 +17,7 @@ func _ready() -> void:
 
 func _update_tooltip() -> void:
 	var duration: float = Global.current_project.frames[frame].duration
-	var duration_sec: float = duration * (1.0 / Global.current_project.fps)
+	var duration_sec := duration * (1.0 / Global.current_project.fps)
 	var duration_str := str(duration_sec)
 	if "." in duration_str:  # If its a decimal value
 		duration_str = "%.2f" % duration_sec  # Up to 2 decimal places
@@ -25,9 +27,9 @@ func _update_tooltip() -> void:
 func _button_pressed() -> void:
 	if Input.is_action_just_released("left_mouse"):
 		Global.canvas.selection.transform_content_confirm()
-		var prev_curr_frame: int = Global.current_project.current_frame
+		var prev_curr_frame := Global.current_project.current_frame
 		if Input.is_action_pressed("shift"):
-			var frame_diff_sign = sign(frame - prev_curr_frame)
+			var frame_diff_sign := sign(frame - prev_curr_frame)
 			if frame_diff_sign == 0:
 				frame_diff_sign = 1
 			for i in range(prev_curr_frame, frame + frame_diff_sign, frame_diff_sign):
@@ -50,15 +52,20 @@ func _button_pressed() -> void:
 
 	elif Input.is_action_just_released("right_mouse"):
 		if Global.current_project.frames.size() == 1:
-			popup_menu.set_item_disabled(0, true)
+			popup_menu.set_item_disabled(REMOVE, true)
-			popup_menu.set_item_disabled(2, true)
+			popup_menu.set_item_disabled(MOVE_LEFT, true)
-			popup_menu.set_item_disabled(3, true)
+			popup_menu.set_item_disabled(MOVE_RIGHT, true)
+			popup_menu.set_item_disabled(REVERSE, true)
 		else:
-			popup_menu.set_item_disabled(0, false)
+			popup_menu.set_item_disabled(REMOVE, false)
+			if Global.current_project.selected_cels.size() > 1:
+				popup_menu.set_item_disabled(REVERSE, false)
+			else:
+				popup_menu.set_item_disabled(REVERSE, true)
 			if frame > 0:
-				popup_menu.set_item_disabled(2, false)
+				popup_menu.set_item_disabled(MOVE_LEFT, false)
 			if frame < Global.current_project.frames.size() - 1:
-				popup_menu.set_item_disabled(3, false)
+				popup_menu.set_item_disabled(MOVE_RIGHT, false)
 		popup_menu.popup(Rect2(get_global_mouse_position(), Vector2.ONE))
 		pressed = !pressed
 	elif Input.is_action_just_released("middle_mouse"):
@@ -70,19 +77,21 @@ func _button_pressed() -> void:
 
 func _on_PopupMenu_id_pressed(id: int) -> void:
 	match id:
-		0:  # Remove Frame
+		REMOVE:
 			Global.animation_timeline.delete_frames()
-		1:  # Clone Frame
+		CLONE:
 			Global.animation_timeline.copy_frames()
-		2:  # Move Left
+		MOVE_LEFT:
 			change_frame_order(-1)
-		3:  # Move Right
+		MOVE_RIGHT:
 			change_frame_order(1)
-		4:  # Frame Properties
+		PROPERTIES:
 			frame_properties.popup_centered()
 			Global.dialog_open(true)
 			frame_properties.set_frame_label(frame)
 			frame_properties.set_frame_dur(Global.current_project.frames[frame].duration)
+		REVERSE:
+			Global.animation_timeline.reverse_frames()
 
 
 func change_frame_order(rate: int) -> void:

src/UI/Timeline/FrameButton.tscn

@@ -20,7 +20,7 @@ __meta__ = {
 margin_right = 20.0
 margin_bottom = 20.0
 mouse_default_cursor_shape = 2
-items = [ "Remove Frame", null, 0, false, true, -1, 0, null, "", false, "Clone Frame", null, 0, false, false, -1, 0, null, "", false, "Move Left", null, 0, false, true, -1, 0, null, "", false, "Move Right", null, 0, false, true, -1, 0, null, "", false, "Frame Properties", null, 0, false, false, -1, 0, null, "", false ]
+items = [ "Remove Frame", null, 0, false, true, -1, 0, null, "", false, "Clone Frame", null, 0, false, false, -1, 0, null, "", false, "Move Left", null, 0, false, true, -1, 0, null, "", false, "Move Right", null, 0, false, true, -1, 0, null, "", false, "Frame Properties", null, 0, false, false, -1, 0, null, "", false, "Reverse Frames", null, 0, false, true, 5, 0, null, "", false ]
 __meta__ = {
 "_edit_use_anchors_": false
 }