Performance boost

src/Autoload/DrawingAlgos.gd

@@ -25,39 +25,39 @@ func blend_layers(
 	only_selected_cels := false,
 	only_selected_layers := false,
 ) -> void:
-	var frame_index := project.frames.find(frame)
+	var frame_index: int = project.frames.find(frame)
 	var previous_ordered_layers: Array[int] = project.ordered_layers
 	project.order_layers(frame_index)
 	var textures: Array[Image] = []
 	# Nx4 texture, where N is the number of layers and the first row are the blend modes,
 	# the second are the opacities, the third are the origins and the fourth are the
 	# clipping mask booleans.
-	var metadata_image := Image.create(project.layers.size(), 4, false, Image.FORMAT_R8)
+	var metadata_image: Image = Image.create(project.layers.size(), 4, false, Image.FORMAT_R8)
 	for i in project.layers.size():
-		var ordered_index := project.ordered_layers[i]
-		var layer := project.layers[ordered_index]
-		var include := true if layer.is_visible_in_hierarchy() else false
+		var ordered_index: int = project.ordered_layers[i]
+		var layer: BaseLayer = project.layers[ordered_index]
+		var include: bool = true if layer.is_visible_in_hierarchy() else false
 		if only_selected_cels and include:
 			var test_array := [frame_index, i]
 			if not test_array in project.selected_cels:
 				include = false
 		if only_selected_layers and include:
-			var layer_is_selected := false
+			var layer_is_selected: bool = false
 			for selected_cel in project.selected_cels:
 				if i == selected_cel[1]:
 					layer_is_selected = true
 					break
 			if not layer_is_selected:
 				include = false
-		var cel := frame.cels[ordered_index]
+		var cel: BaseCel = frame.cels[ordered_index]
 		if DisplayServer.get_name() == "headless":
 			blend_layers_headless(image, project, layer, cel, origin)
 		else:
 			if layer is GroupLayer and layer.blend_mode != BaseLayer.BlendModes.PASS_THROUGH:
-				var cel_image := (layer as GroupLayer).blend_children(frame)
+				var cel_image: Image = (layer as GroupLayer).blend_children(frame)
 				textures.append(cel_image)
 			else:
-				var cel_image := layer.display_effects(cel)
+				var cel_image: Image = layer.display_effects(cel)
 				textures.append(cel_image)
 			if (
 				layer.is_blended_by_ancestor()
@@ -67,13 +67,13 @@ func blend_layers(
 				include = false
 			set_layer_metadata_image(layer, cel, metadata_image, ordered_index, include)
 	if DisplayServer.get_name() != "headless":
-		var texture_array := Texture2DArray.new()
+		var texture_array: Texture2DArray = Texture2DArray.new()
 		texture_array.create_from_images(textures)
 		var params := {
 			"layers": texture_array,
 			"metadata": ImageTexture.create_from_image(metadata_image),
 		}
-		var blended := Image.create(project.size.x, project.size.y, false, image.get_format())
+		var blended: Image = Image.create(project.size.x, project.size.y, false, image.get_format())
 		var gen := ShaderImageEffect.new()
 		gen.generate_image(blended, blend_layers_shader, params, project.size)
 		image.blend_rect(blended, Rect2i(Vector2i.ZERO, project.size), origin)

src/Autoload/Export.gd

@@ -149,7 +149,14 @@ func process_data(project := Global.current_project) -> void:
 			process_spritesheet(project)
 
 
-func process_spritesheet(project := Global.current_project) -> void:
+func process_spritesheet(project := Global.current_project, info_cache: Dictionary = {}) -> void:
+	## info_cache stores the position of frame in the spritesheet and recycles the last created
+	## spritesheet to construct a new one (only if info_cache is provided).
+	## This causes significant performance boost for higher row or column values
+	## (no significant increase in lower values).
+	var old_spritesheet: Image
+	if not info_cache.is_empty():
+		old_spritesheet = processed_images[0].image
 	processed_images.clear()
 	# Range of frames determined by tags
 	var frames := _calculate_frames(project)
@@ -192,6 +199,11 @@ func process_spritesheet(project := Global.current_project) -> void:
 	var width := project.size.x * spritesheet_columns
 	var height := project.size.y * spritesheet_rows
 	var whole_image := Image.create(width, height, false, Image.FORMAT_RGBA8)
+	if not info_cache.is_empty() and old_spritesheet:
+		whole_image.blend_rect(
+			old_spritesheet, Rect2i(Vector2i.ZERO, old_spritesheet.get_size()), Vector2i.ZERO
+		)
+	var old_origins = info_cache.values()
 	var origin := Vector2i.ZERO
 	var hh := 0
 	var vv := 0
@@ -252,8 +264,17 @@ func process_spritesheet(project := Global.current_project) -> void:
 				origin.y = project.size.y * tag_origins[0]
 				origin.x = 0
 				tag_origins[0] += 1
+		old_origins.erase(origin)
+		if frame in info_cache:
+			if info_cache[frame] == origin:
+				continue
+			else:
+				whole_image.fill_rect(Rect2i(origin, project.size), Color.TRANSPARENT)
+		info_cache[frame] = origin
 		_blend_layers(whole_image, frame, origin)
-
+	## remove redundant origins from image
+	for useless in old_origins:
+		whole_image.fill_rect(Rect2i(useless, project.size), Color.TRANSPARENT)
 	processed_images.append(ProcessedImage.new(whole_image, 0))
 
 
@@ -671,7 +692,7 @@ func _blend_layers(
 			# Attempt to read the image data directly from the pxo file, without having to blend
 			# This is mostly useful for when running Pixelorama in headless mode
 			# To handle exporting from a CLI
-			var zip_reader := ZIPReader.new()
+			var zip_reader: ZIPReader = ZIPReader.new()
 			var err := zip_reader.open(project.save_path)
 			if err == OK:
 				var frame_index := project.frames.find(frame) + 1
@@ -679,8 +700,8 @@ func _blend_layers(
 				if zip_reader.file_exists(image_path):
 					# "Include blended" must be toggled on when saving the pxo file
 					# in order for this to work.
-					var image_data := zip_reader.read_file(image_path)
-					var loaded_image := Image.create_from_data(
+					var image_data: PackedByteArray = zip_reader.read_file(image_path)
+					var loaded_image: Image = Image.create_from_data(
 						project.size.x,
 						project.size.y,
 						image.has_mipmaps(),
@@ -698,8 +719,8 @@ func _blend_layers(
 	elif export_layers == SELECTED_LAYERS:
 		DrawingAlgos.blend_layers(image, frame, origin, project, false, true)
 	else:
-		var layer := project.layers[export_layers - 2]
-		var layer_image := Image.new()
+		var layer: BaseLayer = project.layers[export_layers - 2]
+		var layer_image: Image = Image.new()
 		if layer is GroupLayer:
 			layer_image.copy_from(layer.blend_children(frame, Vector2i.ZERO))
 		else:

src/UI/Dialogs/ExportDialog.gd

@@ -6,7 +6,7 @@ signal about_to_preview(dict: Dictionary)
 
 var preview_current_frame := 0
 var preview_frames: Array[Texture2D] = []
-
+var spritesheet_info_cache = {}
 # Allow custom exporters to be added
 var image_exports: Array[Export.FileFormat] = [
 	Export.FileFormat.PNG,
@@ -31,7 +31,7 @@ var _preview_images: Array[Export.ProcessedImage]
 @onready var previews: GridContainer = $"%Previews"
 
 @onready var spritesheet_orientation: OptionButton = $"%Orientation"
-@onready var spritesheet_lines_count: SpinBox = $"%LinesCount"
+@onready var spritesheet_lines_count: ValueSlider = $"%LinesCount"
 @onready var spritesheet_lines_count_label: Label = $"%LinesCountLabel"
 
 @onready var frames_option_button: OptionButton = $"%Frames"
@@ -51,6 +51,7 @@ var _preview_images: Array[Export.ProcessedImage]
 @onready var export_progress_popup: Window = $ExportProgressBar
 @onready var export_progress_bar := %ProgressBar as ProgressBar
 @onready var frame_timer: Timer = $FrameTimer
+@onready var spritesheet_update_timer: Timer = %SpritesheetUpdateTimer
 
 
 func _ready() -> void:
@@ -84,7 +85,8 @@ func show_tab() -> void:
 			)
 		Export.ExportTab.SPRITESHEET:
 			frame_timer.stop()
-			Export.process_spritesheet()
+			spritesheet_info_cache.clear()
+			Export.process_spritesheet(Global.current_project, spritesheet_info_cache)
 			spritesheet_orientation.selected = Export.orientation
 			spritesheet_lines_count.max_value = Export.number_of_frames
 			spritesheet_lines_count.value = Export.lines_count
@@ -121,6 +123,7 @@ func add_image_preview(image: Image, canvas_number: int = -1) -> void:
 	var container := create_preview_container()
 	var preview := create_preview_rect()
 	preview.texture = ImageTexture.create_from_image(image)
+	preview.expand_mode = TextureRect.EXPAND_IGNORE_SIZE
 	container.add_child(preview)
 
 	if canvas_number != -1:
@@ -145,6 +148,7 @@ func add_animated_preview() -> void:
 	var preview := create_preview_rect()
 	preview.name = "Preview"
 	preview.texture = preview_frames[preview_current_frame]
+	preview.expand_mode = TextureRect.EXPAND_IGNORE_SIZE
 	container.add_child(preview)
 
 	previews.add_child(container)
@@ -305,9 +309,8 @@ func _on_Orientation_item_selected(id: Export.Orientation) -> void:
 	Export.orientation = id
 	_handle_orientation_ui()
 	spritesheet_lines_count.value = Export.frames_divided_by_spritesheet_lines()
-	Export.process_spritesheet()
-	update_dimensions_label()
-	set_preview()
+	## Due to the above line, we don't have to process the spritesheet again
+	## the value_changed signal will do this for us.
 
 
 func _handle_orientation_ui() -> void:
@@ -326,9 +329,8 @@ func _handle_orientation_ui() -> void:
 
 func _on_LinesCount_value_changed(value: float) -> void:
 	Export.lines_count = value
-	Export.process_spritesheet()
-	update_dimensions_label()
-	set_preview()
+	## Check if spritesheet needs to be updated (This is required when orientation gets changed)
+	spritesheet_update_timer.start()
 
 
 func _on_Direction_item_selected(id: Export.AnimationDirection) -> void:
@@ -478,3 +480,9 @@ func _on_Layers_item_selected(id: int) -> void:
 
 func _on_SeparatorCharacter_text_changed(new_text: String) -> void:
 	Export.separator_character = new_text
+
+
+func _on_spritesheet_update_timer_timeout() -> void:
+	Export.process_spritesheet(Global.current_project, spritesheet_info_cache)
+	update_dimensions_label()
+	set_preview()

src/UI/Dialogs/ExportDialog.tscn

@@ -1,8 +1,9 @@
-[gd_scene load_steps=5 format=3 uid="uid://clgu8wb5o6oup"]
+[gd_scene load_steps=6 format=3 uid="uid://clgu8wb5o6oup"]
 
 [ext_resource type="Script" path="res://src/UI/Dialogs/ExportDialog.gd" id="1"]
 [ext_resource type="PackedScene" uid="uid://3pmb60gpst7b" path="res://src/UI/Nodes/TransparentChecker.tscn" id="2"]
 [ext_resource type="Script" path="res://src/UI/Nodes/CollapsibleContainer.gd" id="3"]
+[ext_resource type="PackedScene" uid="uid://yjhp0ssng2mp" path="res://src/UI/Nodes/ValueSlider.tscn" id="3_u6gtq"]
 [ext_resource type="Script" path="res://src/UI/Nodes/ValueSlider.gd" id="4"]
 
 [node name="ExportDialog" type="ConfirmationDialog"]
@@ -84,6 +85,7 @@ item_count = 4
 popup/item_0/text = "Columns"
 popup/item_0/id = 1
 popup/item_1/text = "Rows"
+popup/item_1/id = 1
 popup/item_2/text = "Tags by column"
 popup/item_2/id = 2
 popup/item_3/text = "Tags by row"
@@ -94,11 +96,12 @@ unique_name_in_owner = true
 layout_mode = 2
 text = "Columns:"
 
-[node name="LinesCount" type="SpinBox" parent="VBoxContainer/VSplitContainer/VBoxContainer/GridContainer" groups=["ExportSpritesheetOptions"]]
+[node name="LinesCount" parent="VBoxContainer/VSplitContainer/VBoxContainer/GridContainer" groups=["ExportSpritesheetOptions"] instance=ExtResource("3_u6gtq")]
 unique_name_in_owner = true
+custom_minimum_size = Vector2(0, 0)
 layout_mode = 2
-size_flags_horizontal = 3
-mouse_default_cursor_shape = 2
+focus_mode = 0
+theme_type_variation = &""
 min_value = 1.0
 max_value = 1000.0
 value = 1.0
@@ -358,6 +361,11 @@ size_flags_horizontal = 3
 
 [node name="FrameTimer" type="Timer" parent="."]
 
+[node name="SpritesheetUpdateTimer" type="Timer" parent="."]
+unique_name_in_owner = true
+wait_time = 0.2
+one_shot = true
+
 [connection signal="about_to_popup" from="." to="." method="_on_ExportDialog_about_to_show"]
 [connection signal="confirmed" from="." to="." method="_on_ExportDialog_confirmed"]
 [connection signal="tab_clicked" from="VBoxContainer/TabBar" to="." method="_on_Tabs_tab_clicked"]
@@ -384,3 +392,4 @@ size_flags_horizontal = 3
 [connection signal="confirmed" from="FileExistsAlert" to="." method="_on_FileExistsAlert_confirmed"]
 [connection signal="custom_action" from="FileExistsAlert" to="." method="_on_FileExistsAlert_custom_action"]
 [connection signal="timeout" from="FrameTimer" to="." method="_on_FrameTimer_timeout"]
+[connection signal="timeout" from="SpritesheetUpdateTimer" to="." method="_on_spritesheet_update_timer_timeout"]