GNOME: Add a new option to control the color of the kitty window titlebar

docs/changelog.rst

@@ -32,6 +32,9 @@ To update |kitty|, :doc:`follow the instructions <binary>`.
 - GNOME: Fix maximize state not being remembered when focus changes and window
   decorations are hidden (:iss:`3507`)
 
+- GNOME: Add a new :opt:`wayland_titlebar_color` option to control the color of the
+  kitty window titlebar
+
 - Fix reading :option:`kitty --session` from ``STDIN`` not working when the
   :option:`kitty --detach` option is used (:iss:`3523`)
 

glfw/glfw.py

@@ -218,6 +218,7 @@ def generate_wrappers(glfw_header: str) -> None:
     const char* glfwGetPrimarySelectionString(GLFWwindow* window, void)
     int glfwGetNativeKeyForName(const char* key_name, int case_sensitive)
     void glfwRequestWaylandFrameEvent(GLFWwindow *handle, unsigned long long id, GLFWwaylandframecallbackfunc callback)
+    bool glfwWaylandSetTitlebarColor(GLFWwindow *handle, uint32_t color, bool use_system_color)
     unsigned long long glfwDBusUserNotify(const char *app_name, const char* icon, const char *summary, const char *body, \
 const char *action_text, int32_t timeout, GLFWDBusnotificationcreatedfun callback, void *data)
     void glfwDBusSetUserNotificationHandler(GLFWDBusnotificationactivatedfun handler)

glfw/wl_client_side_decorations.c

@@ -146,6 +146,17 @@ static void
 render_title_bar(_GLFWwindow *window, bool to_front_buffer) {
     const bool is_focused = window->id == _glfw.focusedWindowId;
     uint32_t bg_color = is_focused ? active_bg_color : passive_bg_color;
+    uint32_t fg_color = is_focused ? 0xff444444 : 0xff888888;
+    if (decs.use_custom_titlebar_color) {
+        bg_color = 0xff000000 | (decs.titlebar_color & 0xffffff);
+        double red = ((bg_color >> 16) & 0xFF) / 255.0;
+        double green = ((bg_color >> 8) & 0xFF) / 255.0;
+        double blue = (bg_color & 0xFF) / 255.0;
+        double luma = 0.2126 * red + 0.7152 * green + 0.0722 * blue;
+        if (luma < 0.5) {
+            fg_color = is_focused ? 0xffeeeeee : 0xff888888;
+        }
+    }
     uint8_t *output = to_front_buffer ? decs.top.buffer.data.front : decs.top.buffer.data.back;
 
     // render shadow part
@@ -169,7 +180,6 @@ render_title_bar(_GLFWwindow *window, bool to_front_buffer) {
     // render text part
     output += decs.top.buffer.stride * margin;
     if (window->wl.title && window->wl.title[0] && _glfw.callbacks.draw_text) {
-        uint32_t fg_color = is_focused ? 0xff444444 : 0xff888888;
         if (_glfw.callbacks.draw_text((GLFWwindow*)window, window->wl.title, fg_color, bg_color, output, decs.top.buffer.width, decs.top.buffer.height - margin, 0, 0, 0)) return;
     }
     for (uint32_t *px = (uint32_t*)output, *end = (uint32_t*)(output + decs.top.buffer.size_in_bytes); px < end; px++) {
@@ -413,3 +423,16 @@ set_csd_window_geometry(_GLFWwindow *window, int32_t *width, int32_t *height) {
         *height -= decs.metrics.visible_titlebar_height;
     }
 }
+
+void
+set_titlebar_color(_GLFWwindow *window, uint32_t color, bool use_system_color) {
+    bool use_custom_color = !use_system_color;
+    if (use_custom_color != decs.use_custom_titlebar_color || color != decs.titlebar_color) {
+        decs.use_custom_titlebar_color = use_custom_color;
+        decs.titlebar_color = color;
+    }
+    if (window->decorated && decs.top.surface) {
+        update_title_bar(window);
+        damage_csd(top, decs.top.buffer.front);
+    }
+}

glfw/wl_client_side_decorations.h

@@ -14,3 +14,4 @@ void free_csd_surfaces(_GLFWwindow *window);
 void change_csd_title(_GLFWwindow *window);
 bool ensure_csd_resources(_GLFWwindow *window);
 void set_csd_window_geometry(_GLFWwindow *window, int32_t *width, int32_t *height);
+void set_titlebar_color(_GLFWwindow *window, uint32_t color, bool use_system_color);

glfw/wl_platform.h

@@ -195,6 +195,9 @@ typedef struct _GLFWwindowWayland
             size_t for_decoration_size, stride, segments, corner_size;
         } shadow_tile;
         monotonic_t last_click_on_top_decoration_at;
+
+        uint32_t titlebar_color;
+        bool use_custom_titlebar_color;
     } decorations;
 
     struct {

glfw/wl_window.c

@@ -2001,3 +2001,12 @@ GLFWAPI unsigned long long glfwDBusUserNotify(const char *app_name, const char*
 GLFWAPI void glfwDBusSetUserNotificationHandler(GLFWDBusnotificationactivatedfun handler) {
     glfw_dbus_set_user_notification_activated_handler(handler);
 }
+
+GLFWAPI bool glfwWaylandSetTitlebarColor(GLFWwindow *handle, uint32_t color, bool use_system_color) {
+    _GLFWwindow* window = (_GLFWwindow*) handle;
+    if (!window->wl.decorations.serverSide) {
+        set_titlebar_color(window, color, use_system_color);
+        return true;
+    }
+    return false;
+}

kitty/config_data.py

@@ -1260,6 +1260,14 @@ def macos_titlebar_color(x: str) -> int:
     return (color_as_int(to_color(x)) << 8) | 2
 
 
+o('wayland_titlebar_color', 'system', option_type=macos_titlebar_color, long_text=_('''
+Change the color of the kitty window's titlebar on Wayland systems with client side window decorations such as GNOME.
+A value of :code:`system` means to use the default system color,
+a value of :code:`background` means to use the background color
+of the currently active window and finally you can use
+an arbitrary color, such as :code:`#12af59` or :code:`red`.
+'''))
+
 o('macos_titlebar_color', 'system', option_type=macos_titlebar_color, long_text=_('''
 Change the color of the kitty window's titlebar on macOS. A value of :code:`system`
 means to use the default system color, a value of :code:`background` means to use

kitty/fast_data_types.pyi

@@ -437,7 +437,7 @@ def init_cell_program() -> None:
     pass
 
 
-def set_titlebar_color(os_window_id: int, color: int) -> bool:
+def set_titlebar_color(os_window_id: int, color: int, use_system_color: bool = False) -> bool:
     pass
 
 

kitty/glfw-wrapper.c

@@ -432,6 +432,9 @@ load_glfw(const char* path) {
     *(void **) (&glfwRequestWaylandFrameEvent_impl) = dlsym(handle, "glfwRequestWaylandFrameEvent");
     if (glfwRequestWaylandFrameEvent_impl == NULL) dlerror(); // clear error indicator
 
+    *(void **) (&glfwWaylandSetTitlebarColor_impl) = dlsym(handle, "glfwWaylandSetTitlebarColor");
+    if (glfwWaylandSetTitlebarColor_impl == NULL) dlerror(); // clear error indicator
+
     *(void **) (&glfwDBusUserNotify_impl) = dlsym(handle, "glfwDBusUserNotify");
     if (glfwDBusUserNotify_impl == NULL) dlerror(); // clear error indicator
 

kitty/glfw-wrapper.h

@@ -2154,6 +2154,10 @@ typedef void (*glfwRequestWaylandFrameEvent_func)(GLFWwindow*, unsigned long lon
 GFW_EXTERN glfwRequestWaylandFrameEvent_func glfwRequestWaylandFrameEvent_impl;
 #define glfwRequestWaylandFrameEvent glfwRequestWaylandFrameEvent_impl
 
+typedef bool (*glfwWaylandSetTitlebarColor_func)(GLFWwindow*, uint32_t, bool);
+GFW_EXTERN glfwWaylandSetTitlebarColor_func glfwWaylandSetTitlebarColor_impl;
+#define glfwWaylandSetTitlebarColor glfwWaylandSetTitlebarColor_impl
+
 typedef unsigned long long (*glfwDBusUserNotify_func)(const char*, const char*, const char*, const char*, const char*, int32_t, GLFWDBusnotificationcreatedfun, void*);
 GFW_EXTERN glfwDBusUserNotify_func glfwDBusUserNotify_impl;
 #define glfwDBusUserNotify glfwDBusUserNotify_impl

kitty/glfw.c

@@ -573,11 +573,13 @@ intercept_cocoa_fullscreen(GLFWwindow *w) {
 #endif
 
 void
-set_titlebar_color(OSWindow *w, color_type color) {
+set_titlebar_color(OSWindow *w, color_type color, bool use_system_color) {
     if (w->handle && (!w->last_titlebar_color || (w->last_titlebar_color & 0xffffff) != (color & 0xffffff))) {
         w->last_titlebar_color = (1 << 24) | (color & 0xffffff);
 #ifdef __APPLE__
-        cocoa_set_titlebar_color(glfwGetCocoaWindow(w->handle), color);
+        if (!use_system_color) cocoa_set_titlebar_color(glfwGetCocoaWindow(w->handle), color);
+#else
+        if (global_state.is_wayland && glfwWaylandSetTitlebarColor) glfwWaylandSetTitlebarColor(w->handle, color, use_system_color);
 #endif
     }
 }

kitty/state.c

@@ -918,9 +918,10 @@ PYWRAP1(focus_os_window) {
 PYWRAP1(set_titlebar_color) {
     id_type os_window_id;
     unsigned int color;
-    PA("KI", &os_window_id, &color);
+    int use_system_color = 0;
+    PA("KI|p", &os_window_id, &color, &use_system_color);
     WITH_OS_WINDOW(os_window_id)
-        set_titlebar_color(os_window, color);
+        set_titlebar_color(os_window, color, use_system_color);
         Py_RETURN_TRUE;
     END_WITH_OS_WINDOW
     Py_RETURN_FALSE;

kitty/state.h

@@ -256,7 +256,7 @@ void send_image_to_gpu(uint32_t*, const void*, int32_t, int32_t, bool, bool, boo
 void send_sprite_to_gpu(FONTS_DATA_HANDLE fg, unsigned int, unsigned int, unsigned int, pixel*);
 void blank_canvas(float, color_type);
 void blank_os_window(OSWindow *);
-void set_titlebar_color(OSWindow *w, color_type color);
+void set_titlebar_color(OSWindow *w, color_type color, bool use_system_color);
 FONTS_DATA_HANDLE load_fonts_data(double, double, double);
 void send_prerendered_sprites_for_window(OSWindow *w);
 #ifdef __APPLE__

kitty/window.py

@@ -19,7 +19,7 @@
 from .child import ProcessDesc
 from .cli_stub import CLIOptions
 from .config import build_ansi_color_table
-from .constants import appname, wakeup
+from .constants import appname, wakeup, is_macos
 from .fast_data_types import (
     BGIMAGE_PROGRAM, BLIT_PROGRAM, CELL_BG_PROGRAM, CELL_FG_PROGRAM,
     CELL_PROGRAM, CELL_SPECIAL_PROGRAM, DCS, DECORATION, DIM, GLFW_MOD_CONTROL,
@@ -629,13 +629,15 @@ def on_bell(self) -> None:
                 tab.on_bell(self)
 
     def change_titlebar_color(self) -> None:
-        val = self.opts.macos_titlebar_color
+        val = self.opts.macos_titlebar_color if is_macos else self.opts.wayland_titlebar_color
         if val:
             if (val & 0xff) == 1:
                 val = self.screen.color_profile.default_bg
             else:
                 val = val >> 8
             set_titlebar_color(self.os_window_id, val)
+        else:
+            set_titlebar_color(self.os_window_id, 0, True)
 
     def change_colors(self, changes: Dict[DynamicColor, Optional[str]]) -> None:
         dirtied = default_bg_changed = False