Add a theme picker and an Original web theme (#42)

Settings has a Theme row listing Settings.THEMES: Classic (main_theme.tres,
still the default) and Original web (original_web_theme.tres), which looks like
MusicFrontend: orange-bordered buttons, a #333 header and popups, #424242
panels, #4e4e4e alternating rows, a yellow playing song and a light grey
player bar. Picking one sets the root window's theme at once and saves it as
theme_id in settings.cfg, and it is applied at start.

The popup backdrop and score graph follow a theme switch. The top bar has its
own TopBarBackground style. test_theme.gd checks that every theme has
everything main_theme.tres has. The screenshot tool takes a theme id.

Closes #42

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

data/settings.gd

@@ -3,6 +3,9 @@ extends Node
 ##
 ## Registered as the [code]Settings[/code] autoload.
 
+## Emitted when another theme is used, for code that reads theme colours itself.
+signal theme_changed
+
 const MAX_NUMBER_OF_PLAYERS: int = 7
 ## How many letters a search needs before it also finds names with the letters in order
 ## but apart, e.g. "lttp" for "A Link to the Past". Shorter searches only find names
@@ -26,8 +29,14 @@ const SAVED_SETTINGS: Dictionary[String, Array] = {
 		&"inspiration_list_speed",
 	],
 	"window": [&"fullscreen"],
-	"app": [&"last_seen_version"],
+	"app": [&"last_seen_version", &"theme_id"],
 }
+## The looks the game can have, picked in Settings: an id that is saved, the name shown
+## and the theme file. The first is the default. See themes/README.md.
+const THEMES: Array[Dictionary] = [
+	{"id": "classic", "name": "Classic", "path": "res://themes/main_theme.tres"},
+	{"id": "original_web", "name": "Original web", "path": "res://themes/original_web_theme.tres"},
+]
 ## When this environment variable is set, the settings files are kept in that folder
 ## instead of the user's config folder. The tests set it so they never touch the real files.
 const CONFIG_DIR_ENV: String = "MUSICPLAYER_CONFIG_DIR"
@@ -85,6 +94,8 @@ var queue_ids: Dictionary[String, String] = {}
 ## The version the game last showed the About popup for. When it is not [member version],
 ## this version is new and the main window opens the About popup to show what is new.
 var last_seen_version: String = ""
+## The id of the theme in use, one of [constant THEMES].
+var theme_id: String = THEMES[0].id
 ## The folder songs are played from instead of the server, picked in the settings, or null
 ## to use the server. Kept for this session only.
 var music_folder: MusicFolder = null
@@ -103,6 +114,7 @@ var version: String = ProjectSettings.get_setting("application/config/version",
 func _ready() -> void:
 	apply_config(load_config())
 	load_saved_settings()
+	_use_theme(theme_id)
 	if fullscreen:
 		DisplayServer.window_set_mode(DisplayServer.WINDOW_MODE_FULLSCREEN)
 
@@ -246,6 +258,28 @@ func characters_dir() -> String:
 	return ""
 
 
+## Switches the whole game to the theme [param id] from [constant THEMES] and saves the
+## choice. Controls without a theme of their own take it from the root window.
+func apply_theme(id: String) -> void:
+	_use_theme(id)
+	save_settings()
+
+
+## The theme in [constant THEMES] with [param id], or the default one if there is none.
+func theme_entry(id: String) -> Dictionary:
+	for entry: Dictionary in THEMES:
+		if entry.id == id:
+			return entry
+	return THEMES[0]
+
+
+func _use_theme(id: String) -> void:
+	var entry: Dictionary = theme_entry(id)
+	theme_id = entry.id
+	get_tree().root.theme = load(entry.path)
+	theme_changed.emit()
+
+
 func delete_children(node: Node) -> void:
 	for n: Node in node.get_children():
 		node.remove_child(n)

main/TopBar.tscn

@@ -17,6 +17,7 @@ script = ExtResource("top_bar_script")
 layout_mode = 0
 offset_right = 1920.0
 offset_bottom = 56.0
+theme_type_variation = &"TopBarBackground"
 
 [node name="Title" type="Label" parent="." unique_id=1187907861]
 layout_mode = 0

popups/SettingsPopup.tscn

@@ -143,6 +143,21 @@ theme_type_variation = &"HighlightMedium"
 text = "No pictures found"
 text_overrun_behavior = 3
 
+[node name="ThemeRow" type="HBoxContainer" parent="SettingsPanel/VBoxContainer"]
+layout_mode = 2
+
+[node name="Title" type="Label" parent="SettingsPanel/VBoxContainer/ThemeRow"]
+layout_mode = 2
+size_flags_horizontal = 3
+theme_type_variation = &"SettingsRowLabel"
+text = "Theme"
+
+[node name="ThemeButton" type="OptionButton" parent="SettingsPanel/VBoxContainer/ThemeRow"]
+unique_name_in_owner = true
+custom_minimum_size = Vector2(180, 0)
+layout_mode = 2
+focus_mode = 0
+
 [node name="FullscreenButton" type="CheckButton" parent="SettingsPanel/VBoxContainer" unique_id=400304684]
 unique_name_in_owner = true
 layout_mode = 2

popups/popup_backdrop.gd

@@ -27,5 +27,11 @@ static func add_to(parent: Control, popups: Array[BasePopup]) -> PopupBackdrop:
 	return backdrop
 
 
+func _notification(what: int) -> void:
+	# The dimming colour comes from the theme, which can be switched in Settings
+	if what == NOTIFICATION_THEME_CHANGED:
+		color = get_theme_color(&"backdrop", &"Palette")
+
+
 func _update() -> void:
 	visible = _popups.any(func(popup: BasePopup) -> bool: return popup.visible)

popups/score_graph.gd

@@ -19,6 +19,12 @@ var _history: ScoreHistory
 var _winning_score: int = 0
 
 
+func _notification(what: int) -> void:
+	# The colours come from the theme, which can be switched in Settings
+	if what == NOTIFICATION_THEME_CHANGED:
+		queue_redraw()
+
+
 ## Shows [param history]. The y axis goes up to [param winning_score], or higher if
 ## someone has more points. A winning score of 0 draws no winning line.
 func show_history(history: ScoreHistory, winning_score: int) -> void:

popups/settings_popup.gd

@@ -1,9 +1,9 @@
 class_name SettingsPopup
 extends BasePopup
-## The application settings: which MusicServer or music folder to play from, fullscreen,
-## how many songs to download ahead, whether to prefer less played soundtracks and whether
-## plays count in the statistics, and a button that opens the folder the settings are
-## kept in. Opened from the Settings button in the top bar.
+## The application settings: which MusicServer or music folder to play from, the theme,
+## fullscreen, how many songs to download ahead, whether to prefer less played soundtracks
+## and whether plays count in the statistics, and a button that opens the folder the
+## settings are kept in. Opened from the Settings button in the top bar.
 ##
 ## A music folder (see [MusicFolder]) is used instead of the server until Use server is
 ## pressed or the game is closed. The settings that need the server are off meanwhile.
@@ -25,6 +25,7 @@ const PADDING: Vector2 = Vector2(20, 12)
 @onready var settings_panel: Panel = %SettingsPanel
 @onready var select_server_button: OptionButton = %SelectServerButton
 @onready var fullscreen_button: CheckButton = %FullscreenButton
+@onready var theme_button: OptionButton = %ThemeButton
 @onready var cache_label: Label = %CacheLabel
 @onready var lower_cache_button: Button = %LowerCacheButton
 @onready var increase_cache_button: Button = %IncreaseCacheButton
@@ -56,6 +57,10 @@ var _panel_middle_y: float = 0.0
 func _ready() -> void:
 	for server: String in Settings.servers:
 		select_server_button.add_item(server)
+	for entry: Dictionary in Settings.THEMES:
+		theme_button.add_item(entry.name)
+	theme_button.select(Settings.THEMES.find(Settings.theme_entry(Settings.theme_id)))
+	theme_button.item_selected.connect(select_theme)
 	fullscreen_button.button_pressed = Settings.fullscreen
 	select_server_button.select(Settings.selected_server)
 	cache_label.text = str(Playlist.number_of_tracks_to_preload)
@@ -83,6 +88,11 @@ func _ready() -> void:
 	_show_music_source()
 
 
+## Switches to the theme at [param index] in [constant Settings.THEMES] at once.
+func select_theme(index: int) -> void:
+	Settings.apply_theme(Settings.THEMES[index].id)
+
+
 func fullscreen() -> void:
 	Settings.set_fullscreen(!Settings.fullscreen)
 

tests/integration/test_theme.gd

@@ -15,6 +15,7 @@ const STYLES: Dictionary = {
 	"WindowBackground": "Panel",
 	"PopupBackground": "Panel",
 	"StepButton": "Button",
+	"TopBarBackground": "PanelContainer",
 	"PlayerList": "PanelContainer",
 	"PlayerCharacter": "PanelContainer",
 	"PlayerCharacterHover": "PanelContainer",
@@ -171,3 +172,31 @@ func test_japanese_fallback_keeps_the_line_height_of_godots_font() -> void:
 		assert_float(_theme.default_font.get_height(size)) \
 				.override_failure_message("Line height at size %d" % size) \
 				.is_equal(builtin.get_height(size))
+
+
+func test_every_theme_has_everything_the_main_theme_has() -> void:
+	var data_types: Array[Theme.DataType] = [Theme.DATA_TYPE_COLOR, Theme.DATA_TYPE_CONSTANT,
+			Theme.DATA_TYPE_FONT, Theme.DATA_TYPE_FONT_SIZE, Theme.DATA_TYPE_ICON,
+			Theme.DATA_TYPE_STYLEBOX]
+	for entry: Dictionary in Settings.THEMES:
+		var other: Theme = load(entry.path)
+		assert_object(other).override_failure_message(entry.path + " is missing").is_not_null()
+		for theme_type: String in _theme.get_type_list():
+			assert_str(String(other.get_type_variation_base(theme_type))) \
+					.override_failure_message("%s: %s" % [entry.name, theme_type]) \
+					.is_equal(String(_theme.get_type_variation_base(theme_type)))
+			for data_type: Theme.DataType in data_types:
+				for item: String in _theme.get_theme_item_list(data_type, theme_type):
+					assert_bool(other.has_theme_item(data_type, item, theme_type)) \
+							.override_failure_message("%s has no %s/%s" % [entry.name,
+									theme_type, item]).is_true()
+
+
+func test_every_theme_has_its_own_name_and_id() -> void:
+	var ids: Array = Settings.THEMES.map(func(entry: Dictionary) -> String: return entry.id)
+	var names: Array = Settings.THEMES.map(func(entry: Dictionary) -> String: return entry.name)
+
+	assert_str(Settings.THEMES[0].path).is_equal(THEME_PATH)
+	for list: Array in [ids, names]:
+		for value: String in list:
+			assert_int(list.count(value)).override_failure_message(value).is_equal(1)

tests/integration/test_theme_picker.gd

@@ -0,0 +1,74 @@
+extends MainWindowTestSuite
+## Picking a theme in Settings switches the whole game's look at once and is saved.
+
+var _settings: SettingsPopup
+
+
+func before_test() -> void:
+	await super()
+	_settings = _window.get_node("SettingsPopup")
+
+
+func after_test() -> void:
+	Settings.apply_theme(Settings.THEMES[0].id)
+	await super()
+
+
+func _pick(theme_name: String) -> void:
+	var index: int = Settings.THEMES.map(
+			func(entry: Dictionary) -> String: return entry.name).find(theme_name)
+	_settings.theme_button.select(index)
+	_settings.theme_button.item_selected.emit(index)
+	await _runner.simulate_frames(1)
+
+
+func test_picker_lists_every_theme_and_shows_the_one_in_use() -> void:
+	var names: Array[String] = []
+	for index: int in _settings.theme_button.item_count:
+		names.append(_settings.theme_button.get_item_text(index))
+
+	assert_array(names).contains_exactly(["Classic", "Original web"])
+	assert_str(_settings.theme_button.get_item_text(_settings.theme_button.selected)) \
+			.is_equal("Classic")
+
+
+func test_picking_a_theme_switches_the_look_at_once() -> void:
+	var button: Button = _window.get_node("TopBar/%SyncButton")
+	var classic_text: Color = button.get_theme_color(&"font_color")
+	var panel: Panel = _window.get_node("SettingsPopup/SettingsPanel")
+	var popup_style: StyleBox = panel.get_theme_stylebox(&"panel")
+
+	await _pick("Original web")
+
+	assert_str(Settings.theme_id).is_equal("original_web")
+	assert_str(_window.get_tree().root.theme.resource_path) \
+			.is_equal("res://themes/original_web_theme.tres")
+	assert_object(panel.get_theme_stylebox(&"panel")).is_not_same(popup_style)
+	# The web version's buttons have orange text
+	assert_bool(button.get_theme_color(&"font_color") != classic_text).is_true()
+
+
+func test_chosen_theme_is_saved() -> void:
+	await _pick("Original web")
+
+	var saved: ConfigFile = ConfigFile.new()
+	assert_int(saved.load(Settings.saved_settings_path())).is_equal(OK)
+	assert_str(saved.get_value("app", "theme_id")).is_equal("original_web")
+
+
+func test_backdrop_and_graph_follow_the_theme() -> void:
+	var backdrop: PopupBackdrop = _window.get_node("PopupBackdrop")
+	var classic: Color = backdrop.color
+
+	await _pick("Original web")
+
+	assert_object(backdrop.color).is_equal(backdrop.get_theme_color(&"backdrop", &"Palette"))
+	assert_bool(backdrop.color != classic).is_true()
+
+
+func test_unknown_theme_falls_back_to_the_default() -> void:
+	Settings.apply_theme("no_such_theme")
+
+	assert_str(Settings.theme_id).is_equal("classic")
+	assert_str(_window.get_tree().root.theme.resource_path) \
+			.is_equal("res://themes/main_theme.tres")

tests/integration/test_theme_picker.gd.uid

@@ -0,0 +1 @@
+uid://de1hpddu212xs

tests/unit/test_settings_files.gd

@@ -6,7 +6,7 @@ const SAVED_VALUES: Dictionary = {
 	&"auto_repeat_song": false, &"stop_after_current": false, &"hide_next_track": false,
 	&"hide_beginning": true, &"hide_for_seconds": 7.0, &"hide_length": true,
 	&"hide_ticks": true, &"winning_score": 13, &"inspiration_list_speed": 4,
-	&"fullscreen": true, &"last_seen_version": "1.2.3",
+	&"fullscreen": true, &"last_seen_version": "1.2.3", &"theme_id": "original_web",
 }
 
 var _snapshot: AutoloadSnapshot

themes/README.md

@@ -1,17 +1,35 @@
 # Themes
 
-The whole look of the game comes from one theme, `main_theme.tres`. It is the project
-theme (Project Settings → GUI → Theme → Custom), so every scene uses it without setting
-anything. Scenes and scripts never set colours, font sizes or style boxes themselves;
-they name one of the theme's styles instead, and `tests/integration/test_theme.gd`
-checks that it stays that way.
+The whole look of the game comes from a theme. Scenes and scripts never set colours,
+font sizes or style boxes themselves; they name one of the theme's styles instead, and
+`tests/integration/test_theme.gd` checks that it stays that way.
+
+| Theme | File | |
+|---|---|---|
+| Classic | `main_theme.tres` | The default. Also the project theme (Project Settings → GUI → Theme → Custom), which the editor shows |
+| Original web | `original_web_theme.tres` | Looks like MusicFrontend, the web version: orange-bordered buttons, `#333` header and popups, `#424242` panels, `#4e4e4e` alternating rows, a yellow playing song and a light grey player bar |
+
+## Picking a theme
+
+The themes are listed in `Settings.THEMES` (`data/settings.gd`): an id, the name shown
+and the file. The player picks one in Settings → Theme, and it applies at once.
+`Settings.apply_theme()` sets the theme of the root window, which every control without a
+theme of its own uses, and saves the id as `theme_id` in `settings.cfg`. The saved theme
+is applied when the game starts.
+
+Code that reads theme colours itself redraws on `NOTIFICATION_THEME_CHANGED`, e.g. the
+score graph and the popup backdrop. `Settings.theme_changed` is emitted after a switch.
+
+To see the pictures of the screenshot tour in another theme, pass its id:
+`godot --path . -s tools/take_screenshots.gd -- <dir> original_web`.
 
 ## Making a new theme
 
 1. Copy `main_theme.tres`, e.g. to `dark_blue_theme.tres`.
 2. Open the copy in Godot (double-click it) and change its colours, style boxes and font
    sizes in the theme editor. Keep every style's name.
-3. Point Project Settings → GUI → Theme → Custom at the copy.
+3. Add it to `Settings.THEMES`. `test_theme.gd` checks that it has every style, colour and
+   size that `main_theme.tres` has.
 
 The **font** is the theme's default font, Godot's own Open Sans with Noto Sans JP for
 Japanese text; see `fonts/README.md`.
@@ -32,7 +50,11 @@ inspector or `theme_type_variation` in code:
 |---|---|---|
 | `WindowBackground` | Panel | The background behind everything in the main window |
 | `PopupBackground` | Panel | The panel of every popup: dark, bordered and rounded |
-| `DarkSpacer` | Panel | The dark gaps in the player list and the add player row |
+| `TopBarBackground` | PanelContainer | The bar along the top of the window |
+| `PlayerList` | PanelContainer | The player list, with space around its rows |
+| `PlayerScore` | Label | A player's points (24) |
+| `PlayerCharacter`, `PlayerCharacterHover` | PanelContainer | The frame around a player's character, and the one under the mouse |
+| `StepButton` | Button | The small +1 and -1 buttons, with less padding than other buttons |
 | `CharacterCard` | Panel | A character in the character select popup |
 | `MusicList` | PanelContainer | The list of songs in the quiz |
 | `SongRow`, `SongRowOdd` | PanelContainer | Alternating songs in that list |

themes/main_theme.tres

@@ -1331,6 +1331,8 @@ TitleLarge/base_type = &"Label"
 TitleLarge/font_sizes/font_size = 50
 TitleMedium/base_type = &"Label"
 TitleMedium/font_sizes/font_size = 35
+TopBarBackground/base_type = &"PanelContainer"
+TopBarBackground/styles/panel = SubResource("StyleBoxFlat_wl3gy")
 TooltipLabel/colors/font_color = Color(0.875, 0.875, 0.875, 1)
 TooltipLabel/colors/font_outline_color = Color(0, 0, 0, 1)
 TooltipLabel/colors/font_shadow_color = Color(0, 0, 0, 0)

tools/take_screenshots.gd

@@ -3,6 +3,7 @@ extends SceneTree
 ##
 ## Usage:
 ##   MUSICPLAYER_CONFIG_DIR=$(mktemp -d) godot --path . -s tools/take_screenshots.gd -- <dir>
+##       [<theme id>]
 ##
 ## Setting [code]MUSICPLAYER_CONFIG_DIR[/code] keeps your saved quiz settings out of the
 ## pictures.
@@ -10,6 +11,9 @@ extends SceneTree
 ## Writes [code]<state>.png[/code] for each state and [code]layout.json[/code] with where
 ## every node is in each state. With [code]--headless[/code] only the layout is written.
 ## Compare two runs with [code]tools/compare_screenshots.py[/code].
+##
+## The pictures use the default theme, or the theme with the given id from
+## [code]Settings.THEMES[/code], e.g. [code]original_web[/code].
 
 const SIZE: Vector2i = Vector2i(1920, 1080)
 
@@ -37,6 +41,10 @@ func _take() -> void:
 	viewport.render_target_update_mode = SubViewport.UPDATE_ALWAYS
 	root.add_child(viewport)
 	var main: Control = load("res://main/MainWindow.tscn").instantiate()
+	if args.size() > 1:
+		# The game sets the root window's theme, which the viewport here is not under
+		var settings: Node = root.get_node("Settings")
+		main.theme = load(settings.theme_entry(args[1]).path)
 	viewport.add_child(main)
 
 	var layout: Dictionary = {}