Added a new brush type - Random Brushes

They're like File brushes, but each time you draw, expect to see something different!

To make a random brush, just put the images you want in the same folder (under the main Brushes folder of course), and make sure their filename starts with "%".

I also changed _process() to _input() in Canvas.gd, so there may be some unexpected behavior.

Scripts/BrushButton.gd

@@ -2,6 +2,8 @@ extends BaseButton
 
 export var brush_type = Global.BRUSH_TYPES.PIXEL
 export var custom_brush_index := -2
+# warning-ignore:unused_class_variable
+var random_brushes := []
 
 func _on_BrushButton_pressed() -> void:
 	# Change left brush

Scripts/Canvas.gd

@@ -12,6 +12,7 @@ var frame_texture_rect : TextureRect
 var current_pixel := Vector2.ZERO #pretty much same as mouse_pos, but can be accessed externally
 var previous_mouse_pos := Vector2.ZERO
 var previous_mouse_pos_for_lines := Vector2.ZERO
+var can_undo := true
 var cursor_inside_canvas := false
 var previous_action := "None"
 var mouse_inside_canvas := false #used for undo
@@ -80,9 +81,10 @@ func camera_zoom() -> void:
 	Global.camera_preview.offset = size / 2
 
 # warning-ignore:unused_argument
-func _process(delta : float) -> void:
+func _input(event) -> void:
 	sprite_changed_this_frame = false
-	update()
+	if Global.current_frame == frame:
+		update()
 	current_pixel = get_local_mouse_position() - location
 	var mouse_pos := current_pixel
 	var mouse_pos_floored := mouse_pos.floor()
@@ -90,8 +92,8 @@ func _process(delta : float) -> void:
 	var mouse_in_canvas := point_in_rectangle(mouse_pos, location, location + size)
 	var current_mouse_button := "None"
 	var current_action := "None"
-	var fill_area := 0 #For the bucket tool
-	#For the LightenDarken tool
+	var fill_area := 0 # For the bucket tool
+	# For the LightenDarken tool
 	var ld := 0
 	var ld_amount := 0.1
 	if Input.is_mouse_button_pressed(BUTTON_LEFT):
@@ -126,13 +128,13 @@ func _process(delta : float) -> void:
 				Global.right_cursor.visible = false
 				Input.set_custom_mouse_cursor(null)
 
-	#Handle Undo/Redo
+	# Handle Undo/Redo
 	var can_handle : bool = mouse_in_canvas && Global.can_draw && Global.has_focus && !made_line
 	var mouse_pressed : bool = (Input.is_action_just_pressed("left_mouse") && !Input.is_action_pressed("right_mouse")) || (Input.is_action_just_pressed("right_mouse") && !Input.is_action_pressed("left_mouse"))
 
-	#If we're already pressing a mouse button and we haven't handled undo yet,...
-	#... it means that the cursor was outside the canvas. Then, ...
-	#simulate "just pressed" logic the moment the cursor gets inside the canvas
+	# If we're already pressing a mouse button and we haven't handled undo yet,...
+	#. .. it means that the cursor was outside the canvas. Then, ...
+	# simulate "just pressed" logic the moment the cursor gets inside the canvas
 	if Input.is_action_pressed("left_mouse") || Input.is_action_pressed("right_mouse"):
 		if mouse_in_canvas && Global.undos < Global.undo_redo.get_version():
 			mouse_pressed = true
@@ -151,7 +153,7 @@ func _process(delta : float) -> void:
 			if previous_action != "None" && previous_action != "RectSelect" && current_action != "ColorPicker":
 				handle_redo("Draw")
 
-	match current_action: #Handle current tool
+	match current_action: # Handle current tool
 		"Pencil":
 			var current_color : Color
 			if current_mouse_button == "left_mouse":
@@ -316,18 +318,20 @@ func _process(delta : float) -> void:
 		update_texture(current_layer_index, (Input.is_action_just_released("left_mouse") || Input.is_action_just_released("right_mouse")))
 
 func handle_undo(action : String) -> void:
+	if !can_undo:
+		return
 	var canvases := []
 	var layer_index := -1
-	if Global.animation_timer.is_stopped(): #if we're not animating, store only the current canvas
+	if Global.animation_timer.is_stopped(): # if we're not animating, store only the current canvas
 		canvases = [self]
 		layer_index = current_layer_index
-	else: #If we're animating, store all canvases
+	else: # If we're animating, store all canvases
 		canvases = Global.canvases
 	Global.undos += 1
 	Global.undo_redo.create_action(action)
 	for c in canvases:
-		#I'm not sure why I have to unlock it, but...
-		#...if I don't, it doesn't work properly
+		# I'm not sure why I have to unlock it, but...
+		# ...if I don't, it doesn't work properly
 		c.layers[c.current_layer_index][0].unlock()
 		var data = c.layers[c.current_layer_index][0].data
 		c.layers[c.current_layer_index][0].lock()
@@ -338,6 +342,8 @@ func handle_undo(action : String) -> void:
 		Global.undo_redo.add_undo_property(Global, "selected_pixels", selected_pixels)
 	Global.undo_redo.add_undo_method(Global, "undo", canvases, layer_index)
 
+	can_undo = false
+
 func handle_redo(action : String) -> void:
 	if Global.undos < Global.undo_redo.get_version():
 		return
@@ -356,6 +362,8 @@ func handle_redo(action : String) -> void:
 	Global.undo_redo.add_do_method(Global, "redo", canvases, layer_index)
 	Global.undo_redo.commit_action()
 
+	can_undo = true
+
 func update_texture(layer_index : int, update_frame_tex := true) -> void:
 	layers[layer_index][1].create_from_image(layers[layer_index][0], 0)
 	var layer_container := get_layer_container(layer_index)
@@ -533,7 +541,17 @@ func draw_pixel(pos : Vector2, color : Color, current_mouse_button : String, cur
 			brush_size = Global.left_brush_size
 			brush_type = Global.current_left_brush_type
 			brush_index = Global.custom_left_brush_index
-			custom_brush_image = Global.custom_left_brush_image
+			if brush_type != Global.BRUSH_TYPES.RANDOM_FILE:
+				custom_brush_image = Global.custom_left_brush_image
+			else: # Handle random brush
+				var brush_button = Global.file_brush_container.get_child(brush_index + 2)
+				var random_index = randi() % brush_button.random_brushes.size()
+				custom_brush_image = brush_button.random_brushes[random_index]
+				var custom_brush_size = custom_brush_image.get_size()
+				custom_brush_image.resize(custom_brush_size.x * brush_size, custom_brush_size.y * brush_size, Image.INTERPOLATE_NEAREST)
+				custom_brush_image = Global.blend_image_with_color(custom_brush_image, color, Global.left_interpolate_spinbox.value / 100)
+				custom_brush_image.lock()
+
 			horizontal_mirror = Global.left_horizontal_mirror
 			vertical_mirror = Global.left_vertical_mirror
 			ld = Global.left_ld
@@ -542,7 +560,17 @@ func draw_pixel(pos : Vector2, color : Color, current_mouse_button : String, cur
 			brush_size = Global.right_brush_size
 			brush_type = Global.current_right_brush_type
 			brush_index = Global.custom_right_brush_index
-			custom_brush_image = Global.custom_right_brush_image
+			if brush_type != Global.BRUSH_TYPES.RANDOM_FILE:
+				custom_brush_image = Global.custom_right_brush_image
+			else: # Handle random brush
+				var brush_button = Global.file_brush_container.get_child(brush_index + 2)
+				var random_index = randi() % brush_button.random_brushes.size()
+				custom_brush_image = brush_button.random_brushes[random_index]
+				var custom_brush_size = custom_brush_image.get_size()
+				custom_brush_image.resize(custom_brush_size.x * brush_size, custom_brush_size.y * brush_size, Image.INTERPOLATE_NEAREST)
+				custom_brush_image = Global.blend_image_with_color(custom_brush_image, color, Global.right_interpolate_spinbox.value / 100)
+				custom_brush_image.lock()
+
 			horizontal_mirror = Global.right_horizontal_mirror
 			vertical_mirror = Global.right_vertical_mirror
 			ld = Global.right_ld

Scripts/Global.gd

@@ -83,7 +83,7 @@ var onion_skinning_future_rate := 0
 var onion_skinning_blue_red := false
 
 # Brushes
-enum BRUSH_TYPES {PIXEL, CIRCLE, FILE, CUSTOM}
+enum BRUSH_TYPES {PIXEL, CIRCLE, FILE, RANDOM_FILE, CUSTOM}
 # warning-ignore:unused_class_variable
 var left_brush_size := 1
 # warning-ignore:unused_class_variable
@@ -215,6 +215,7 @@ var palette_import_file_dialog : FileDialog
 var error_dialog : AcceptDialog
 
 func _ready() -> void:
+	randomize()
 	# Load settings from the config file
 	config_cache.load("user://cache.ini")
 
@@ -434,14 +435,14 @@ func frame_changed(value : int) -> void:
 	canvas = canvases[current_frame]
 	canvas.visible = true
 	canvas.generate_layer_panels()
-	#Make all frame buttons unpressed
+	# Make all frame buttons unpressed
 	for c in canvases:
 		var text_color := Color.white
 		if theme_type == "Gold" || theme_type == "Light":
 			text_color = Color.black
 		c.frame_button.get_node("FrameButton").pressed = false
 		c.frame_button.get_node("FrameID").add_color_override("font_color", text_color)
-	#Make only the current frame button pressed
+	# Make only the current frame button pressed
 	canvas.frame_button.get_node("FrameButton").pressed = true
 	canvas.frame_button.get_node("FrameID").add_color_override("font_color", Color("#3c5d75"))
 
@@ -451,7 +452,7 @@ func create_brush_button(brush_img : Image, brush_type := BRUSH_TYPES.CUSTOM, hi
 	var brush_button = load("res://Prefabs/BrushButton.tscn").instance()
 	brush_button.brush_type = brush_type
 	brush_button.custom_brush_index = custom_brushes.size() - 1
-	if brush_type == BRUSH_TYPES.FILE:
+	if brush_type == BRUSH_TYPES.FILE || brush_type == BRUSH_TYPES.RANDOM_FILE:
 		brush_container = file_brush_container
 	else:
 		brush_container = project_brush_container
@@ -459,6 +460,8 @@ func create_brush_button(brush_img : Image, brush_type := BRUSH_TYPES.CUSTOM, hi
 	brush_tex.create_from_image(brush_img, 0)
 	brush_button.get_child(0).texture = brush_tex
 	brush_button.hint_tooltip = hint_tooltip
+	if brush_type == BRUSH_TYPES.RANDOM_FILE:
+		brush_button.random_brushes.append(brush_img)
 	brush_container.add_child(brush_button)
 
 func remove_brush_buttons() -> void:

Scripts/Import.gd

@@ -14,18 +14,28 @@ func import_brushes(path : String) -> void:
 
 func find_brushes(brushes_dir : Directory, path : String) -> Array:
 	var subdirectories := []
+	var found_random_brush := 0
 	brushes_dir.open(path)
 	brushes_dir.list_dir_begin(true)
 	var file := brushes_dir.get_next()
 	while file != "":
-		print(file)
 		if file.get_extension().to_upper() == "PNG":
 			var image := Image.new()
 			var err := image.load(path.plus_file(file))
 			if err == OK:
-				image.convert(Image.FORMAT_RGBA8)
-				Global.custom_brushes.append(image)
-				Global.create_brush_button(image, Global.BRUSH_TYPES.FILE, file.trim_suffix(".png"))
+				if "%" in file:
+					if found_random_brush == 0:
+						found_random_brush = Global.file_brush_container.get_child_count()
+						image.convert(Image.FORMAT_RGBA8)
+						Global.custom_brushes.append(image)
+						Global.create_brush_button(image, Global.BRUSH_TYPES.RANDOM_FILE, file.trim_suffix(".png"))
+					else:
+						var brush_button = Global.file_brush_container.get_child(found_random_brush)
+						brush_button.random_brushes.append(image)
+				else:
+					image.convert(Image.FORMAT_RGBA8)
+					Global.custom_brushes.append(image)
+					Global.create_brush_button(image, Global.BRUSH_TYPES.FILE, file.trim_suffix(".png"))
 		elif file.get_extension() == "": # Probably a directory
 			var subdir := "./%s" % [file]
 			if brushes_dir.dir_exists(subdir): # If it's an actual directory