Share settings page helpers, add GUI cursor/scale API

- move create_trackbar_setting/update_trackbar_label/create_checkbox from
  settings_audio/display/graphics pages to core:settings_common module
- GUI scale trackbar shows the really applied scale, e.g. '3 (effective 2)'
- add gui.get_scale(), gui.get_max_scale(), gui.get_cursor_pos() (UI units);
  document that input.get_mouse_pos() returns window pixels
- InventoryView default color is defined once (InventoryView::DEFAULT_COLOR)
  instead of duplicated literals; 'color' attribute still overrides it

doc/en/scripting/builtins/libgui.md

@@ -16,6 +16,17 @@ gui.str(text: str, context: str) -> str
 -- Returns size of the main container (window).
 gui.get_viewport() -> {int, int}
 
+-- Returns current GUI scale: window pixels per one UI unit (1..4).
+-- Set by the display.gui-scale setting and limited by window size.
+gui.get_scale() -> int
+
+-- Returns maximal GUI scale that fits the current window size.
+gui.get_max_scale() -> int
+
+-- Returns cursor position in UI units (unlike input.get_mouse_pos,
+-- which returns window pixels). Use it to position UI elements.
+gui.get_cursor_pos() -> {number, number}
+
 -- Returns environment (global variables table) of the specified document.
 gui.get_env(document: str) -> table
 ```

doc/en/scripting/builtins/libinput.md

@@ -55,7 +55,8 @@ end, document.root)
 input.get_mouse_pos() --> {int, int}
 ```
 
-Returns cursor screen position.
+Returns cursor screen position in window pixels.
+To get position in UI units (affected by GUI scale) use `gui.get_cursor_pos()`.
 
 ```lua
 input.get_mouse_delta() --> {int, int}

doc/ru/scripting/builtins/libgui.md

@@ -31,6 +31,17 @@ gui.str(text: string, context: string) -> string
 -- Возвращает размер главного контейнера (окна).
 gui.get_viewport() -> {number, number}
 
+-- Возвращает текущий масштаб интерфейса: пикселей окна в одной единице UI (1..4).
+-- Задаётся настройкой display.gui-scale и ограничивается размером окна.
+gui.get_scale() -> int
+
+-- Возвращает максимальный масштаб интерфейса, помещающийся в текущее окно.
+gui.get_max_scale() -> int
+
+-- Возвращает позицию курсора в единицах UI (в отличие от input.get_mouse_pos,
+-- возвращающей пиксели окна). Используйте для позиционирования элементов UI.
+gui.get_cursor_pos() -> {number, number}
+
 -- Возвращает окружение (глобальные переменные) указанного документа.
 gui.get_env(document: string) -> table
 

doc/ru/scripting/builtins/libinput.md

@@ -29,7 +29,8 @@ input.set_enabled(bindname: string, flag: boolean)
 
 ## Курсор мыши
 ```lua
--- Возвращает позицию курсора на экране.
+-- Возвращает позицию курсора на экране в пикселях окна.
+-- Для позиции в единицах UI (с учётом масштаба) используйте gui.get_cursor_pos().
 input.get_mouse_pos() -> {number, number}
 
 -- Возращает дельту позиции курсора.

res/layouts/pages/settings_audio.xml.lua

@@ -1,30 +1,7 @@
-function create_trackbar_setting(id, name, step, postfix, tooltip)
-    local info = app.get_setting_info(id)
-    postfix = postfix or ""
-    tooltip = tooltip or ""
-    document.root:add(gui.template("track_setting", {
-        id=id,
-        name=gui.str(name, "settings"),
-        value=app.get_setting(id),
-        min=info.min,
-        max=info.max,
-        step=step,
-        postfix=postfix,
-        tooltip=gui.str(tooltip, "settings")
-    }))
-    update_trackbar_label(app.get_setting(id), id, name, postfix)
-end
-
-function update_trackbar_label(x, id, name, postfix)
-    app.set_setting(id, x)
-    -- updating label
-    document[id..".L"].text = string.format(
-        "%s: %s%s", 
-        gui.str(name, "settings"),
-        app.str_setting(id),
-        postfix
-    )
-end
+local settings = require "core:settings_common".new(document, {})
+-- templates call these functions by name, so they must be global
+create_trackbar_setting = settings.create_trackbar_setting
+update_trackbar_label = settings.update_trackbar_label
 
 function update_checkbox_setting(id, value)
     app.set_setting(id, value)
@@ -43,12 +20,8 @@ function update_checkbox_setting(id, value)
     end
 end
 
-function create_checkbox(id, name, tooltip)
-    tooltip = tooltip or ''
-    document.root:add(string.format(
-        "<checkbox consumer='function(x) update_checkbox_setting(\"%s\", x) end' checked='%s' tooltip='%s'>%s</checkbox>",
-        id, app.str_setting(id), gui.str(tooltip, "settings"), gui.str(name, "settings")
-    ))
+local function create_audio_checkbox(id, name, tooltip)
+    settings.create_checkbox(id, name, tooltip, "update_checkbox_setting")
     update_checkbox_setting(id, app.get_setting(id))
 end
 
@@ -103,6 +76,6 @@ function on_open()
         selectbox.value = app.get_setting("audio.input-device")
     end
 
-    create_checkbox("audio.recording-enabled", "Microphone access", "audio.recording-enabled.tooltip")
-    create_checkbox("audio.acoustic-effects", "Acoustic effects", "audio.acoustic-effects.tooltip")
+    create_audio_checkbox("audio.recording-enabled", "Microphone access", "audio.recording-enabled.tooltip")
+    create_audio_checkbox("audio.acoustic-effects", "Acoustic effects", "audio.acoustic-effects.tooltip")
 end

res/layouts/pages/settings_display.xml.lua

@@ -10,57 +10,24 @@ tostring_overrides["display.framerate"] = function(x)
 end
 
 tostring_overrides["display.gui-scale"] = function(x)
+    -- scale is limited by the window size, show what is really applied
+    local effective = gui.get_max_scale()
+    if x > 0 then
+        effective = math.min(x, effective)
+    end
     if x == 0 then
-        return gui.str("Auto")
-    else
-        return tostring(x)
+        return string.format("%s (%d)", gui.str("Auto"), effective)
+    elseif effective < x then
+        return string.format("%d (%s %d)", x, gui.str("Effective"), effective)
     end
+    return tostring(x)
 end
 
-function create_trackbar_setting(id, name, step, postfix, tooltip, changeonrelease)
-    local info = app.get_setting_info(id)
-    postfix = postfix or ""
-    tooltip = tooltip or ""
-    changeonrelease = changeonrelease or ""
-    document.root:add(gui.template("track_setting", {
-        id=id,
-        name=gui.str(name, "settings"),
-        value=app.get_setting(id),
-        min=info.min,
-        max=info.max,
-        step=step,
-        postfix=postfix,
-        tooltip=tooltip,
-        changeonrelease=changeonrelease
-    }))
-    update_trackbar_label(app.get_setting(id), id, name, postfix)
-end
-
-function update_trackbar_label(x, id, name, postfix)
-    local str
-    local func = tostring_overrides[id]
-    if func then
-        str = func(x)
-    else
-        str = app.str_setting(id)
-    end
-    -- updating label
-    document[id..".L"].text = string.format(
-        "%s: %s%s",
-        gui.str(name, "settings"),
-        str,
-        postfix
-    )
-end
-
-function create_checkbox(id, name, tooltip)
-    tooltip = tooltip or ''
-    document.root:add(string.format(
-        "<checkbox consumer='function(x) app.set_setting(\"%s\", x) end' checked='%s' tooltip='%s'>%s</checkbox>",
-        id, app.str_setting(id), gui.str(tooltip, "settings"), gui.str(name, "settings")
-    ))
-end
-
+local settings = require "core:settings_common".new(document, {tostring_overrides=tostring_overrides})
+-- templates call these functions by name, so they must be global
+create_trackbar_setting = settings.create_trackbar_setting
+update_trackbar_label = settings.update_trackbar_label
+create_checkbox = settings.create_checkbox
 
 function on_open()
     create_trackbar_setting("camera.fov", "FOV", 1, "°")

res/layouts/pages/settings_graphics.xml.lua

@@ -1,39 +1,8 @@
-function create_trackbar_setting(id, name, step, postfix, tooltip, changeonrelease)
-    local info = app.get_setting_info(id)
-    postfix = postfix or ""
-    tooltip = tooltip or ""
-    changeonrelease = changeonrelease or ""
-    document.root:add(gui.template("track_setting", {
-        id=id,
-        name=gui.str(name, "settings"),
-        value=app.get_setting(id),
-        min=info.min,
-        max=info.max,
-        step=step,
-        postfix=postfix,
-        tooltip=tooltip,
-        changeonrelease=changeonrelease
-    }))
-    update_trackbar_label(app.get_setting(id), id, name, postfix)
-end
-
-function update_trackbar_label(x, id, name, postfix)
-    -- updating label
-    document[id..".L"].text = string.format(
-        "%s: %s%s",
-        gui.str(name, "settings"),
-        app.str_setting(id),
-        postfix
-    )
-end
-
-function create_checkbox(id, name, tooltip)
-    tooltip = tooltip or ''
-    document.root:add(string.format(
-        "<checkbox consumer='function(x) app.set_setting(\"%s\", x) end' checked='%s' tooltip='%s'>%s</checkbox>",
-        id, app.str_setting(id), gui.str(tooltip, "settings"), gui.str(name, "settings")
-    ))
-end
+local settings = require "core:settings_common".new(document, {})
+-- templates call these functions by name, so they must be global
+create_trackbar_setting = settings.create_trackbar_setting
+update_trackbar_label = settings.update_trackbar_label
+create_checkbox = settings.create_checkbox
 
 function on_open()
     create_trackbar_setting("chunks.load-distance", "Load Distance", 1)

res/modules/settings_common.lua

@@ -0,0 +1,84 @@
+-- Common helpers for settings pages (res/layouts/pages/settings_*.xml.lua).
+--
+-- Usage in a page script:
+--
+--   local settings = require "core:settings_common".new(document, {
+--       tostring_overrides = {["display.framerate"] = function(x) ... end}
+--   })
+--   -- templates call these functions by name, so they must be global
+--   create_trackbar_setting = settings.create_trackbar_setting
+--   update_trackbar_label = settings.update_trackbar_label
+--   create_checkbox = settings.create_checkbox
+
+local settings_common = {}
+
+--- Create helpers bound to the page document.
+--- @param document the page document
+--- @param options table (optional) with fields:
+---   tostring_overrides: {[setting_id] = function(value) -> string}
+function settings_common.new(document, options)
+    options = options or {}
+    local tostring_overrides = options.tostring_overrides or {}
+    local this = {}
+
+    --- Update trackbar label (called by the track_setting template)
+    function this.update_trackbar_label(x, id, name, postfix)
+        local str
+        local func = tostring_overrides[id]
+        if func then
+            str = func(x)
+        else
+            str = app.str_setting(id)
+        end
+        document[id..".L"].text = string.format(
+            "%s: %s%s",
+            gui.str(name, "settings"),
+            str,
+            postfix
+        )
+    end
+
+    --- Add a trackbar bound to the setting
+    --- @param changeonrelease apply value only when mouse is released
+    function this.create_trackbar_setting(
+        id, name, step, postfix, tooltip, changeonrelease
+    )
+        local info = app.get_setting_info(id)
+        postfix = postfix or ""
+        tooltip = tooltip or ""
+        changeonrelease = changeonrelease or ""
+        document.root:add(gui.template("track_setting", {
+            id=id,
+            name=gui.str(name, "settings"),
+            value=app.get_setting(id),
+            min=info.min,
+            max=info.max,
+            step=step,
+            postfix=postfix,
+            tooltip=tooltip,
+            changeonrelease=changeonrelease
+        }))
+        this.update_trackbar_label(app.get_setting(id), id, name, postfix)
+    end
+
+    --- Add a checkbox bound to the setting
+    --- @param consumer name of a global page function(id, value) called on
+    --- change instead of just setting the value (optional)
+    function this.create_checkbox(id, name, tooltip, consumer)
+        tooltip = tooltip or ""
+        local action
+        if consumer then
+            action = string.format("%s(\"%s\", x)", consumer, id)
+        else
+            action = string.format("app.set_setting(\"%s\", x)", id)
+        end
+        document.root:add(string.format(
+            "<checkbox consumer='function(x) %s end' checked='%s' tooltip='%s'>%s</checkbox>",
+            action, app.str_setting(id), gui.str(tooltip, "settings"), gui.str(name, "settings")
+        ))
+    end
+
+    return this
+end
+
+return settings_common

res/texts/ru_RU.txt

@@ -13,6 +13,7 @@ Description=Описание
 Converting world...=Выполняется конвертация мира...
 Unlimited=Неограниченно
 Auto=Авто
+Effective=действует
 Chat=Чат
 Console=Консоль
 Log=Лог

src/graphics/ui/GUI.cpp

@@ -93,13 +93,18 @@ void GUI::onAssetsLoad(Assets* assets) {
 static constexpr glm::uvec2 MIN_UI_SIZE {640, 480};
 static constexpr int MAX_SCALE = 4;
 
-int GUI::calcScale(const glm::uvec2& viewport) const {
+int GUI::calcMaxScale(const glm::uvec2& viewport) {
     int maxFit = 1;
     while (maxFit < MAX_SCALE &&
            viewport.x / (maxFit + 1) >= MIN_UI_SIZE.x &&
            viewport.y / (maxFit + 1) >= MIN_UI_SIZE.y) {
         maxFit++;
     }
+    return maxFit;
+}
+
+int GUI::calcScale(const glm::uvec2& viewport) const {
+    int maxFit = calcMaxScale(viewport);
     int value = engine.getSettings().display.guiScale.get();
     if (value <= 0) {
         return maxFit; // auto
@@ -111,6 +116,10 @@ int GUI::getScale() const {
     return scale;
 }
 
+int GUI::getMaxScale() const {
+    return calcMaxScale(engine.getWindow().getSize());
+}
+
 CursorState GUI::getCursor() const {
     auto cursor = input.getCursor();
     cursor.pos /= static_cast<float>(scale);

src/graphics/ui/GUI.hpp

@@ -95,6 +95,7 @@ namespace gui {
         bool doubleClicked = false;
         bool debug = false;
 
+        static int calcMaxScale(const glm::uvec2& viewport);
         int calcScale(const glm::uvec2& viewport) const;
         CursorState getScaledCursor() const;
 
@@ -134,6 +135,9 @@ namespace gui {
         /// @brief Get current GUI scale: window pixels per one UI unit
         int getScale() const;
 
+        /// @brief Get maximal GUI scale that fits the current window size
+        int getMaxScale() const;
+
         /// @brief Get cursor state in UI coordinates
         CursorState getCursor() const;
 

src/graphics/ui/elements/InventoryView.cpp

@@ -78,7 +78,7 @@ void InventoryBuilder::addGrid(
     if (addpanel) {
         auto panel =
             std::make_shared<gui::Container>(gui, glm::vec2(width, height));
-        view->setColor(glm::vec4(0.122f, 0.122f, 0.122f, 0.878f));
+        view->setColor(InventoryView::DEFAULT_COLOR);
         view->add(panel, pos);
     }
 

src/graphics/ui/elements/InventoryView.hpp

@@ -160,6 +160,8 @@ namespace gui {
 
         static const int SLOT_INTERVAL = 4;
         static const int SLOT_SIZE = ITEM_ICON_SIZE;
+        /// @brief Default background color (can be overridden by 'color' attribute)
+        static inline const glm::vec4 DEFAULT_COLOR {0.122f, 0.122f, 0.122f, 0.878f};
     };
 
     class InventoryBuilder {

src/graphics/ui/gui_xml.cpp

@@ -860,7 +860,7 @@ static std::shared_ptr<UINode> read_inventory(
     UiXmlReader& reader, const xml::xmlelement& element
 ) {
     auto view = std::make_shared<InventoryView>(reader.getGUI());
-    view->setColor(glm::vec4(0.122f, 0.122f, 0.122f, 0.878f));  // TODO: fixme
+    view->setColor(InventoryView::DEFAULT_COLOR);
     reader.addIgnore("slot");
     reader.addIgnore("slots-grid");
     reader.readUINode(reader, element, *view);

src/logic/scripting/lua/libs/libgui.cpp

@@ -1067,6 +1067,20 @@ static int l_gui_getviewport(lua::State* L) {
     return lua::pushvec2(L, engine->getGUI().getContainer()->getSize());
 }
 
+static int l_gui_get_scale(lua::State* L) {
+    return lua::pushinteger(L, engine->getGUI().getScale());
+}
+
+static int l_gui_get_max_scale(lua::State* L) {
+    return lua::pushinteger(L, engine->getGUI().getMaxScale());
+}
+
+static int l_gui_get_cursor_pos(lua::State* L) {
+    if (engine->isHeadless())
+        return 0;
+    return lua::pushvec2(L, engine->getGUI().getCursor().pos);
+}
+
 static int l_gui_clear_markup(lua::State* L) {
     auto lang = lua::require_string(L, 1);
     std::string text = lua::require_string(L, 2);
@@ -1247,6 +1261,9 @@ static int l_screenshot(lua::State* L) {
 const luaL_Reg guilib[] = {
     {"screenshot", lua::wrap<l_screenshot>},
     {"get_viewport", lua::wrap<l_gui_getviewport>},
+    {"get_scale", lua::wrap<l_gui_get_scale>},
+    {"get_max_scale", lua::wrap<l_gui_get_max_scale>},
+    {"get_cursor_pos", lua::wrap<l_gui_get_cursor_pos>},
     {"getattr", lua::wrap<l_gui_getattr>},
     {"setattr", lua::wrap<l_gui_setattr>},
     {"get_env", lua::wrap<l_gui_get_env>},