Add an option to control dragging to resize windows

docs/changelog.rst

@@ -164,6 +164,9 @@ Detailed list of changes
 - Allow dragging tabs in the tab bar to re-order, move to another OS Window or
   detach (:pull:`9296`)
 
+- Allow dragging window borders to resize kitty windows in all the different
+  layouts, controlled by :opt:`window_drag_tolerance` (:pull:`9447`)
+
 - choose-files kitten: Fix JXL image preview not working (:iss:`9323`)
 
 - Fix tab bar rendering glitches when using :opt:`tab_bar_filter` in some

kitty/mouse.c

@@ -254,9 +254,9 @@ contains_mouse(Window *w) {
 }
 
 static void
-border_contains_mouse(BorderRect *br, int tolerance, bool *horizontal, bool *vertical) {
+border_contains_mouse(BorderRect *br, double tolerance, bool *horizontal, bool *vertical) {
     double x = global_state.callback_os_window->mouse_x, y = global_state.callback_os_window->mouse_y;
-    if ((int)br->px.left - tolerance <= x && x < br->px.right + tolerance && (int)br->px.top - tolerance <= y && y < br->px.bottom + tolerance) {
+    if ((int)br->px.left - tolerance <= x && x < (int)br->px.right + tolerance && (int)br->px.top - tolerance <= y && y < (int)br->px.bottom + tolerance) {
         if (br->px.right - br->px.left > br->px.bottom - br->px.top) *horizontal = true; else *vertical = true;
     }
 }
@@ -906,13 +906,15 @@ window_for_event(unsigned int *window_idx, bool *in_tab_bar, int *window_border)
                 (tab_bar.bottom > central.bottom && w->mouse_y >= central.bottom)
            ) *in_tab_bar = true;
     }
-    if (in_central && global_state.callback_os_window->num_tabs > 0) {
+    if (in_central && w->num_tabs > 0) {
         Tab *t = global_state.callback_os_window->tabs + global_state.callback_os_window->active_tab;
         if (window_border) {
             bool horizontal = false, vertical = false;
+            double dpi = (w->fonts_data->logical_dpi_x + w->fonts_data->logical_dpi_y) / 2.;
+            double tolerance = ((long)round((OPT(window_drag_tolerance) * (dpi / 72.0))));
             for (unsigned i = 0; i < t->border_rects.num_border_rects && !(horizontal && vertical); i++) {
                 BorderRect *br = t->border_rects.rect_buf + i;
-                if (br->is_actual_border) border_contains_mouse(br, 0, &horizontal, &vertical);
+                if (br->is_actual_border) border_contains_mouse(br, tolerance, &horizontal, &vertical);
             }
             *window_border = 0;
             if (horizontal) *window_border |= 1;
@@ -1173,9 +1175,6 @@ mouse_event(const int button, int modifiers, int action) {
         mouse_cursor_shape = POINTER_POINTER;
         handle_tab_bar_mouse(button, modifiers, action);
         debug("handled by tab bar\n");
-    } else if (w) {
-        debug("grabbed: %d\n", w->render_data.screen->modes.mouse_tracking_mode != 0);
-        handle_event(w, button, modifiers, window_idx);
     } else if (window_border) {
         debug("window border: %d\n", window_border);
         w = window_for_event(&window_idx, &in_tab_bar, NULL);
@@ -1191,6 +1190,9 @@ mouse_event(const int button, int modifiers, int action) {
             if (r == NULL) { PyErr_Print(); return; }
             if (PyObject_IsTrue(r)) global_state.active_drag_resize = w->id;
         }
+    } else if (w) {
+        debug("grabbed: %d\n", w->render_data.screen->modes.mouse_tracking_mode != 0);
+        handle_event(w, button, modifiers, window_idx);
     } else if (button == GLFW_MOUSE_BUTTON_LEFT && global_state.callback_os_window->mouse_button_pressed[button]) {
         // initial click, clamp it to the closest window
         w = closest_window_for_event(&window_idx);
@@ -1200,7 +1202,10 @@ mouse_event(const int button, int modifiers, int action) {
             handle_event(w, button, modifiers, window_idx);
             clamp_to_window = false;
         } else debug("no window for event\n");
-    } else debug("\n");
+    } else {
+        mouse_cursor_shape = DEFAULT_POINTER;
+        debug("\n");
+    }
     if (mouse_cursor_shape != old_cursor) set_mouse_cursor(mouse_cursor_shape);
 }
 

kitty/options/definition.py

@@ -1457,6 +1457,13 @@
 Note that if you want confirmation when closing individual windows,
 you can map the :ac:`close_window_with_confirmation` action.
 ''')
+
+opt('window_drag_tolerance', '2', option_type='float', ctype='double', long_text='''
+Control dragging window borders to resize kitty windows. This is the tolerance in pts
+for the region around window borders where pressing the left mouse button
+will start the dragging of window borders. Use a large negative value such as -200 to disable
+dragging of borders.
+''')
 egr()  # }}}
 
 
@@ -3847,9 +3854,7 @@
 '''
     )
 
-opt('map_timeout', '0.0',
-    option_type='positive_float', ctype='time',
-    long_text='''
+opt('map_timeout', '0.0', option_type='positive_float', long_text='''
 The default timeout (in seconds) for multi-key mappings and modal keyboard modes.
 If you press the first key(s) of a multi-key mapping and don't press the next
 key within this timeout, the mapping is cancelled and the mode is exited. A value
@@ -3862,8 +3867,7 @@
 
     # This mode will have a 5 second timeout (overrides the global 2 second timeout)
     map --new-mode resize --timeout 5.0 kitty_mod+r
-'''
-    )
+''')
 
 opt('+action_alias', 'launch_tab launch --type=tab --cwd=current',
     option_type='action_alias',

kitty/options/parse.py

@@ -1060,9 +1060,6 @@ def kitten_alias(self, val: str, ans: dict[str, typing.Any]) -> None:
     def kitty_mod(self, val: str, ans: dict[str, typing.Any]) -> None:
         ans['kitty_mod'] = to_modifiers(val)
 
-    def map_timeout(self, val: str, ans: dict[str, typing.Any]) -> None:
-        ans['map_timeout'] = positive_float(val)
-
     def linux_bell_theme(self, val: str, ans: dict[str, typing.Any]) -> None:
         ans['linux_bell_theme'] = str(val)
 
@@ -1123,6 +1120,9 @@ def macos_traditional_fullscreen(self, val: str, ans: dict[str, typing.Any]) ->
     def macos_window_resizable(self, val: str, ans: dict[str, typing.Any]) -> None:
         ans['macos_window_resizable'] = to_bool(val)
 
+    def map_timeout(self, val: str, ans: dict[str, typing.Any]) -> None:
+        ans['map_timeout'] = positive_float(val)
+
     def mark1_background(self, val: str, ans: dict[str, typing.Any]) -> None:
         ans['mark1_background'] = to_color(val)
 
@@ -1472,6 +1472,9 @@ def window_alert_on_bell(self, val: str, ans: dict[str, typing.Any]) -> None:
     def window_border_width(self, val: str, ans: dict[str, typing.Any]) -> None:
         ans['window_border_width'] = window_border_width(val)
 
+    def window_drag_tolerance(self, val: str, ans: dict[str, typing.Any]) -> None:
+        ans['window_drag_tolerance'] = float(val)
+
     def window_logo_alpha(self, val: str, ans: dict[str, typing.Any]) -> None:
         ans['window_logo_alpha'] = unit_float(val)
 

kitty/options/to-c-generated.h

@@ -980,6 +980,19 @@ convert_from_opts_resize_in_steps(PyObject *py_opts, Options *opts) {
     Py_DECREF(ret);
 }
 
+static void
+convert_from_python_window_drag_tolerance(PyObject *val, Options *opts) {
+    opts->window_drag_tolerance = PyFloat_AsDouble(val);
+}
+
+static void
+convert_from_opts_window_drag_tolerance(PyObject *py_opts, Options *opts) {
+    PyObject *ret = PyObject_GetAttrString(py_opts, "window_drag_tolerance");
+    if (ret == NULL) return;
+    convert_from_python_window_drag_tolerance(ret, opts);
+    Py_DECREF(ret);
+}
+
 static void
 convert_from_python_tab_bar_edge(PyObject *val, Options *opts) {
     opts->tab_bar_edge = PyLong_AsLong(val);
@@ -1535,6 +1548,8 @@ convert_opts_from_python_opts(PyObject *py_opts, Options *opts) {
     if (PyErr_Occurred()) return false;
     convert_from_opts_resize_in_steps(py_opts, opts);
     if (PyErr_Occurred()) return false;
+    convert_from_opts_window_drag_tolerance(py_opts, opts);
+    if (PyErr_Occurred()) return false;
     convert_from_opts_tab_bar_edge(py_opts, opts);
     if (PyErr_Occurred()) return false;
     convert_from_opts_tab_bar_margin_height(py_opts, opts);

kitty/options/types.py

@@ -488,6 +488,7 @@
     'wheel_scroll_multiplier',
     'window_alert_on_bell',
     'window_border_width',
+    'window_drag_tolerance',
     'window_logo_alpha',
     'window_logo_path',
     'window_logo_position',
@@ -573,7 +574,6 @@ class Options:
     input_delay: int = 3
     italic_font: FontSpec = FontSpec(family=None, style=None, postscript_name=None, full_name=None, system='auto', axes=(), variable_name=None, features=(), created_from_string='auto')
     kitty_mod: int = 5
-    map_timeout: float = 0.0
     linux_bell_theme: str = '__custom'
     linux_display_server: choices_for_linux_display_server = 'auto'
     listen_on: str = 'none'
@@ -589,6 +589,7 @@ class Options:
     macos_titlebar_color: int = 0
     macos_traditional_fullscreen: bool = False
     macos_window_resizable: bool = True
+    map_timeout: float = 0
     mark1_background: Color = Color(152, 211, 203)
     mark1_foreground: Color = Color(0, 0, 0)
     mark2_background: Color = Color(242, 220, 211)
@@ -679,6 +680,7 @@ class Options:
     wheel_scroll_multiplier: float = 5.0
     window_alert_on_bell: bool = True
     window_border_width: tuple[float, str] = (0.5, 'pt')
+    window_drag_tolerance: float = 2.0
     window_logo_alpha: float = 0.5
     window_logo_path: str | None = None
     window_logo_position: choices_for_window_logo_position = 'bottom-right'

kitty/state.h

@@ -141,6 +141,7 @@ typedef struct Options {
     struct { float thickness; int unit; } underline_exclusion;
     float box_drawing_scale[4];
     double momentum_scroll;
+    double window_drag_tolerance;
 } Options;
 
 typedef struct WindowLogoRenderData {