Add a remote command to control window opacity

Fixes #569

kitty/boss.py

@@ -19,11 +19,11 @@ from .constants import (
     appname, config_dir, editor, set_boss, supports_primary_selection
 )
 from .fast_data_types import (
-    ChildMonitor, create_os_window, current_os_window, destroy_global_data,
+    ChildMonitor, change_background_opacity, create_os_window,
-    destroy_sprite_map, get_clipboard_string,
+    current_os_window, destroy_global_data, destroy_sprite_map,
-    glfw_post_empty_event, layout_sprite_map, mark_os_window_for_close,
+    get_clipboard_string, glfw_post_empty_event, layout_sprite_map,
-    set_clipboard_string, set_dpi_from_os_window, set_in_sequence_mode,
+    mark_os_window_for_close, set_clipboard_string, set_dpi_from_os_window,
-    show_window, toggle_fullscreen, viewport_for_window
+    set_in_sequence_mode, show_window, toggle_fullscreen, viewport_for_window
 )
 from .fonts.render import prerender, resize_fonts, set_font_family
 from .keys import get_shortcut, shortcut_matches
@@ -361,6 +361,9 @@ class Boss:
     def on_dpi_change(self, os_window_id):
         self._change_font_size()
 
+    def _set_os_window_background_opacity(self, os_window_id, opacity):
+        change_background_opacity(os_window_id, opacity)
+
     @property
     def active_tab_manager(self):
         os_window_id = current_os_window()

kitty/child-monitor.c

@@ -614,7 +614,7 @@ static inline void
 render_os_window(OSWindow *os_window, double now, unsigned int active_window_id, color_type active_window_bg, unsigned int num_visible_windows) {
     Tab *tab = os_window->tabs + os_window->active_tab;
     BorderRects *br = &tab->border_rects;
-    draw_borders(br->vao_idx, br->num_border_rects, br->rect_buf, br->is_dirty, os_window->viewport_width, os_window->viewport_height, active_window_bg, num_visible_windows);
+    draw_borders(br->vao_idx, br->num_border_rects, br->rect_buf, br->is_dirty, os_window->viewport_width, os_window->viewport_height, active_window_bg, num_visible_windows, os_window);
     if (TD.screen && os_window->num_tabs > 1) draw_cells(TD.vao_idx, 0, TD.xstart, TD.ystart, TD.dx, TD.dy, TD.screen, os_window, true);
     for (unsigned int i = 0; i < tab->num_windows; i++) {
         Window *w = tab->windows + i;

kitty/cmds.py

@@ -586,6 +586,45 @@ def set_colors(boss, window, payload):
 # }}}
 
 
+# set_background_opacity {{{
+@cmd(
+    'Set the background_opacity',
+    'Set the background opacity for the specified windows. This will only work if you have turned on'
+    ' dynamic_background_opacity in kitty.conf. The background opacity affects all kitty windows in a'
+    ' single os_window. For example: kitty @ set-background-opacity 0.5',
+    options_spec='''\
+--all -a
+type=bool-set
+By default, colors are only changed for the currently active window. This option will
+cause colors to be changed in all windows.
+
+''' + '\n\n' + MATCH_WINDOW_OPTION + '\n\n' + MATCH_TAB_OPTION.replace('--match -m', '--match-tab -t'),
+    argspec='OPACITY'
+)
+def cmd_set_background_opacity(global_opts, opts, args):
+    if len(args) != 1:
+        raise SystemExit('Must specify exactly one argument, the new opacity')
+    opacity = max(0.1, min(float(args[0]), 1.0))
+    return {
+            'opacity': opacity, 'match_window': opts.match,
+            'all': opts.all or opts.reset,
+    }
+
+
+def set_background_opacity(boss, window, payload):
+    if payload['all']:
+        windows = tuple(boss.all_windows)
+    else:
+        windows = (window or boss.active_window,)
+        if payload['match_window']:
+            windows = tuple(boss.match_windows(payload['match_window']))
+            if not windows:
+                raise MatchError(payload['match_window'])
+    for os_window_id in {w.os_window_id for w in windows}:
+        boss._set_os_window_background_opacity(os_window_id, payload['opacity'])
+# }}}
+
+
 cmap = {v.name: v for v in globals().values() if hasattr(v, 'is_cmd')}
 
 

kitty/config.py

@@ -354,6 +354,7 @@ type_map = {
     'macos_option_as_alt': to_bool,
     'macos_titlebar_color': macos_titlebar_color,
     'box_drawing_scale': box_drawing_scale,
+    'dynamic_background_opacity': to_bool,
     'background_opacity': unit_float,
     'dim_opacity': unit_float,
     'tab_separator': tab_separator,

kitty/glfw.c

@@ -365,7 +365,7 @@ create_os_window(PyObject UNUSED *self, PyObject *args) {
         PyErr_SetString(PyExc_ValueError, "Too many windows");
         return NULL;
     }
-    bool want_semi_transparent = (1.0 - OPT(background_opacity) >= 0.01) ? true : false;
+    bool want_semi_transparent = (1.0 - OPT(background_opacity) >= 0.01) || OPT(dynamic_background_opacity);
     glfwWindowHint(GLFW_TRANSPARENT_FRAMEBUFFER, want_semi_transparent);
     GLFWwindow *glfw_window = glfwCreateWindow(width, height, title, NULL, global_state.num_os_windows ? global_state.os_windows[0].handle : NULL);
     if (glfw_window == NULL) {

kitty/kitty.conf

@@ -257,7 +257,10 @@ background       #000000
 # in the editor color scheme. Or use the escape codes to set the terminals
 # default colors in a shell script to launch your editor.
 # Be aware that using a value less than 1.0 is a (possibly significant) performance hit.
+# If you want to dynamically change transparency of windows using the kitty remote control facility,
+# set dynamic_background_opacity to yes
 background_opacity 1.0
+dynamic_background_opacity no
 
 # How much to dim text that has the DIM/FAINT attribute set. 1.0 means no dimming and
 # 0.0 means fully dimmed (i.e. invisible).

kitty/shaders.c

@@ -209,7 +209,7 @@ struct CellUniformData {
 static struct CellUniformData cell_uniform_data = {0, .prev_inactive_text_alpha=-1};
 
 static inline void
-cell_update_uniform_block(ssize_t vao_idx, Screen *screen, int uniform_buffer, GLfloat xstart, GLfloat ystart, GLfloat dx, GLfloat dy, CursorRenderInfo *cursor, bool inverted) {
+cell_update_uniform_block(ssize_t vao_idx, Screen *screen, int uniform_buffer, GLfloat xstart, GLfloat ystart, GLfloat dx, GLfloat dy, CursorRenderInfo *cursor, bool inverted, OSWindow *os_window) {
     struct CellRenderData {
         GLfloat xstart, ystart, dx, dy, sprite_dx, sprite_dy, background_opacity;
 
@@ -239,7 +239,7 @@ cell_update_uniform_block(ssize_t vao_idx, Screen *screen, int uniform_buffer, G
     sprite_tracker_current_layout(&x, &y, &z);
     rd->sprite_dx = 1.0f / (float)x; rd->sprite_dy = 1.0f / (float)y;
     rd->inverted = inverted ? 1 : 0;
-    rd->background_opacity = OPT(background_opacity);
+    rd->background_opacity = os_window->background_opacity;
 
 #define COLOR(name) colorprofile_to_color(screen->color_profile, screen->color_profile->overridden.name, screen->color_profile->configured.name)
     rd->default_fg = COLOR(default_fg); rd->default_bg = COLOR(default_bg); rd->highlight_fg = COLOR(highlight_fg); rd->highlight_bg = COLOR(highlight_bg);
@@ -415,7 +415,7 @@ send_cell_data_to_gpu(ssize_t vao_idx, ssize_t gvao_idx, GLfloat xstart, GLfloat
     if (os_window->clear_count < 2) {
         os_window->clear_count++;
 #define C(shift) (((GLfloat)((OPT(background) >> shift) & 0xFF)) / 255.0f)
-        glClearColor(C(16), C(8), C(0), os_window->is_semi_transparent ? OPT(background_opacity) : 1.0f);
+        glClearColor(C(16), C(8), C(0), os_window->is_semi_transparent ? os_window->background_opacity : 1.0f);
 #undef C
         glClear(GL_COLOR_BUFFER_BIT);
         changed = true;
@@ -430,7 +430,7 @@ draw_cells(ssize_t vao_idx, ssize_t gvao_idx, GLfloat xstart, GLfloat ystart, GL
     CELL_BUFFERS;
     bool inverted = screen_invert_colors(screen);
 
-    cell_update_uniform_block(vao_idx, screen, uniform_buffer, xstart, ystart, dx, dy, &screen->cursor_render_info, inverted);
+    cell_update_uniform_block(vao_idx, screen, uniform_buffer, xstart, ystart, dx, dy, &screen->cursor_render_info, inverted, os_window);
 
     bind_vao_uniform_buffer(vao_idx, uniform_buffer, cell_program_layouts[CELL_PROGRAM].render_data.index);
     bind_vertex_array(vao_idx);
@@ -522,7 +522,7 @@ create_border_vao() {
 }
 
 void
-draw_borders(ssize_t vao_idx, unsigned int num_border_rects, BorderRect *rect_buf, bool rect_data_is_dirty, uint32_t viewport_width, uint32_t viewport_height, color_type active_window_bg, unsigned int num_visible_windows) {
+draw_borders(ssize_t vao_idx, unsigned int num_border_rects, BorderRect *rect_buf, bool rect_data_is_dirty, uint32_t viewport_width, uint32_t viewport_height, color_type active_window_bg, unsigned int num_visible_windows, OSWindow *w) {
     if (num_border_rects) {
         if (rect_data_is_dirty) {
             size_t sz = sizeof(GLuint) * 5 * num_border_rects;
@@ -535,11 +535,14 @@ draw_borders(ssize_t vao_idx, unsigned int num_border_rects, BorderRect *rect_bu
 #define CV3(x) (((float)((x >> 16) & 0xff))/255.f), (((float)((x >> 8) & 0xff))/255.f), (((float)(x & 0xff))/255.f)
         if (!constants_set) {
             constants_set = true;
-            glUniform1f(border_uniform_locations[BORDER_background_opacity], OPT(background_opacity));
+            glUniform1f(border_uniform_locations[BORDER_background_opacity], w->background_opacity);
             glUniform3f(border_uniform_locations[BORDER_active_border_color], CV3(OPT(active_border_color)));
             glUniform3f(border_uniform_locations[BORDER_inactive_border_color], CV3(OPT(inactive_border_color)));
             glUniform3f(border_uniform_locations[BORDER_bell_border_color], CV3(OPT(bell_border_color)));
         }
+        if (OPT(dynamic_background_opacity)) {
+            glUniform1f(border_uniform_locations[BORDER_background_opacity], w->background_opacity);
+        }
         glUniform2ui(border_uniform_locations[BORDER_viewport], viewport_width, viewport_height);
         color_type default_bg = num_visible_windows > 1 ? OPT(background) : active_window_bg;
         glUniform3f(border_uniform_locations[BORDER_default_bg], CV3(default_bg));

kitty/state.c

@@ -81,6 +81,7 @@ add_os_window() {
     memset(ans, 0, sizeof(OSWindow));
     ans->id = ++global_state.os_window_id_counter;
     ans->tab_bar_render_data.vao_idx = create_cell_vao();
+    ans->background_opacity = OPT(background_opacity);
     END_WITH_OS_WINDOW_REFS
     return ans;
 }
@@ -360,6 +361,7 @@ PYWRAP1(set_options) {
     S(cursor_stop_blinking_after, PyFloat_AsDouble);
     S(background_opacity, PyFloat_AsDouble);
     S(dim_opacity, PyFloat_AsDouble);
+    S(dynamic_background_opacity, PyObject_IsTrue);
     S(inactive_text_alpha, PyFloat_AsDouble);
     S(window_padding_width, PyFloat_AsDouble);
     S(cursor_shape, PyLong_AsLong);
@@ -503,6 +505,18 @@ PYWRAP1(mark_tab_bar_dirty) {
     Py_RETURN_NONE;
 }
 
+PYWRAP1(change_background_opacity) {
+    id_type os_window_id;
+    float opacity;
+    PA("Kf", &os_window_id, &opacity);
+    WITH_OS_WINDOW(os_window_id)
+        os_window->background_opacity = opacity;
+        os_window->is_damaged = true;
+        Py_RETURN_TRUE;
+    END_WITH_OS_WINDOW
+    Py_RETURN_FALSE;
+}
+
 static inline bool
 fix_window_idx(Tab *tab, id_type window_id, unsigned int *window_idx) {
     for (id_type fix = 0; fix < tab->num_windows; fix++) {
@@ -630,6 +644,7 @@ static PyMethodDef module_methods[] = {
     MW(mark_os_window_for_close, METH_VARARGS),
     MW(set_titlebar_color, METH_VARARGS),
     MW(mark_tab_bar_dirty, METH_O),
+    MW(change_background_opacity, METH_VARARGS),
     MW(update_window_visibility, METH_VARARGS),
     MW(set_boss, METH_O),
     MW(set_display_state, METH_VARARGS),

kitty/state.h

@@ -27,6 +27,7 @@ typedef struct {
     int adjust_line_height_px, adjust_column_width_px;
     float adjust_line_height_frac, adjust_column_width_frac;
     float background_opacity, dim_opacity;
+    bool dynamic_background_opacity;
     float inactive_text_alpha;
     float window_padding_width;
     Edge tab_bar_edge;
@@ -118,6 +119,7 @@ typedef struct {
     uint32_t offscreen_texture_id;
     unsigned int clear_count;
     color_type last_titlebar_color;
+    float background_opacity;
 } OSWindow;
 
 
@@ -171,7 +173,7 @@ OSWindow* add_os_window();
 OSWindow* current_os_window();
 void os_window_regions(OSWindow*, Region *main, Region *tab_bar);
 bool drag_scroll(Window *, OSWindow*);
-void draw_borders(ssize_t vao_idx, unsigned int num_border_rects, BorderRect *rect_buf, bool rect_data_is_dirty, uint32_t viewport_width, uint32_t viewport_height, color_type, unsigned int);
+void draw_borders(ssize_t vao_idx, unsigned int num_border_rects, BorderRect *rect_buf, bool rect_data_is_dirty, uint32_t viewport_width, uint32_t viewport_height, color_type, unsigned int, OSWindow *w);
 ssize_t create_cell_vao();
 ssize_t create_graphics_vao();
 ssize_t create_border_vao();