theme: add button padding and spacing (#2127)

While at it, separate corner width from button
width. Both are independed and having them
separately improves readability.

docs/labwc-theme.5.scd

@@ -47,12 +47,18 @@ labwc-config(5).
 # THEME ELEMENTS
 
 *border.width*
-	Line width (integer) of border border drawn around window frames.
+	Line width (integer) of border drawn around window frames.
 	Default is 1.
 
+*padding.width*
+	Horizontal padding size, in pixels, between border and first
+	button on the left/right.
+	Default is 0.
+
 *padding.height*
-	Vertical padding size, used for spacing out elements in the window
-	decorations. Default is 3.
+	Vertical padding size, in pixels, used for spacing out elements
+	in the window decorations.
+	Default is 3.
 
 *titlebar.height*
 	Window title bar height.
@@ -122,6 +128,10 @@ labwc-config(5).
 	Width of a titlebar button, in pixels.
 	Default is 26.
 
+*window.button.spacing*
+	Space between titlebar buttons, in pixels.
+	Default is 0.
+
 *window.active.button.unpressed.image.color*
 	Color of the images in titlebar buttons in their default, unpressed,
 	state. This element is for the focused window.

docs/themerc

@@ -7,6 +7,7 @@
 
 # general
 border.width: 1
+padding.width: 0
 padding.height: 3
 
 # The following options has no default, but fallbacks back to
@@ -29,8 +30,9 @@ window.active.label.text.color: #000000
 window.inactive.label.text.color: #000000
 window.label.text.justify: center
 
-# window button width
+# window button width and spacing
 window.button.width: 26
+window.button.spacing: 0
 
 # window buttons
 window.active.button.unpressed.image.color: #000000

include/ssd.h

@@ -79,6 +79,7 @@ struct wlr_scene_node;
  */
 struct ssd *ssd_create(struct view *view, bool active);
 struct border ssd_get_margin(const struct ssd *ssd);
+int ssd_get_corner_width(void);
 void ssd_update_margin(struct ssd *ssd);
 void ssd_set_active(struct ssd *ssd, bool active);
 void ssd_update_title(struct ssd *ssd);

include/theme.h

@@ -27,7 +27,14 @@ struct theme_snapping_overlay {
 
 struct theme {
 	int border_width;
+
+	/*
+	 * the space between title bar border and
+	 * buttons on the left/right/top
+	 */
+	int padding_width;
 	int padding_height;
+
 	int title_height;
 	int menu_overlap_x;
 	int menu_overlap_y;
@@ -48,6 +55,8 @@ struct theme {
 
 	/* button width */
 	int window_button_width;
+	/* the space between buttons */
+	int window_button_spacing;
 
 	/* button colors */
 	float window_active_button_menu_unpressed_image_color[4];

include/view.h

@@ -538,6 +538,7 @@ const char *view_get_string_prop(struct view *view, const char *prop);
 void view_update_title(struct view *view);
 void view_update_app_id(struct view *view);
 void view_reload_ssd(struct view *view);
+int view_get_min_width(void);
 
 void view_set_shade(struct view *view, bool shaded);
 

src/snap.c

@@ -220,8 +220,7 @@ snap_shrink_to_next_edge(struct view *view,
 
 	*geo = view->pending;
 	uint32_t resize_edges;
-	int min_view_width = rc.theme->window_button_width * (
-		wl_list_length(&rc.title_buttons_left) + wl_list_length(&rc.title_buttons_right));
+	int min_width = view_get_min_width();
 
 	/*
 	 * First shrink the view along the relevant edge. The maximum shrink
@@ -230,12 +229,12 @@ snap_shrink_to_next_edge(struct view *view,
 	 */
 	switch (direction) {
 	case VIEW_EDGE_RIGHT:
-		geo->width = MAX(geo->width / 2, min_view_width);
+		geo->width = MAX(geo->width / 2, min_width);
 		geo->x = view->pending.x + view->pending.width - geo->width;
 		resize_edges = WLR_EDGE_LEFT;
 		break;
 	case VIEW_EDGE_LEFT:
-		geo->width = MAX(geo->width / 2, min_view_width);
+		geo->width = MAX(geo->width / 2, min_width);
 		resize_edges = WLR_EDGE_RIGHT;
 		break;
 	case VIEW_EDGE_DOWN:

src/ssd/ssd-border.c

@@ -22,6 +22,7 @@ ssd_border_create(struct ssd *ssd)
 	int width = view->current.width;
 	int height = view_effective_height(view, /* use_pending */ false);
 	int full_width = width + 2 * theme->border_width;
+	int corner_width = ssd_get_corner_width();
 
 	float *color;
 	struct wlr_scene_tree *parent;
@@ -48,8 +49,8 @@ ssd_border_create(struct ssd *ssd)
 		add_scene_rect(&subtree->parts, LAB_SSD_PART_BOTTOM, parent,
 			full_width, theme->border_width, 0, height, color);
 		add_scene_rect(&subtree->parts, LAB_SSD_PART_TOP, parent,
-			width - 2 * theme->window_button_width, theme->border_width,
-			theme->border_width + theme->window_button_width,
+			width - 2 * corner_width, theme->border_width,
+			theme->border_width + corner_width,
 			-(ssd->titlebar.height + theme->border_width), color);
 	} FOR_EACH_END
 
@@ -93,6 +94,7 @@ ssd_border_update(struct ssd *ssd)
 	int width = view->current.width;
 	int height = view_effective_height(view, /* use_pending */ false);
 	int full_width = width + 2 * theme->border_width;
+	int corner_width = ssd_get_corner_width();
 
 	/*
 	 * From here on we have to cover the following border scenarios:
@@ -121,10 +123,10 @@ ssd_border_update(struct ssd *ssd)
 		: 0;
 	int top_width = ssd->titlebar.height <= 0 || ssd->state.was_squared
 		? full_width
-		: width - 2 * theme->window_button_width;
+		: width - 2 * corner_width;
 	int top_x = ssd->titlebar.height <= 0 || ssd->state.was_squared
 		? 0
-		: theme->border_width + theme->window_button_width;
+		: theme->border_width + corner_width;
 
 	struct ssd_part *part;
 	struct wlr_scene_rect *rect;

src/ssd/ssd-extents.c

@@ -76,8 +76,9 @@ ssd_extents_update(struct ssd *ssd)
 	int full_height = height + theme->border_width * 2 + ssd->titlebar.height;
 	int full_width = width + 2 * theme->border_width;
 	int extended_area = SSD_EXTENDED_AREA;
+	int corner_width = ssd_get_corner_width();
 	int corner_size = extended_area + theme->border_width +
-		MIN(theme->window_button_width, width) / 2;
+		MIN(corner_width, width) / 2;
 	int side_width = full_width + extended_area * 2 - corner_size * 2;
 	int side_height = full_height + extended_area * 2 - corner_size * 2;
 

src/ssd/ssd-titlebar.c

@@ -116,6 +116,7 @@ ssd_titlebar_create(struct ssd *ssd)
 	struct view *view = ssd->view;
 	struct theme *theme = view->server->theme;
 	int width = view->current.width;
+	int corner_width = ssd_get_corner_width();
 
 	float *color;
 	struct wlr_scene_tree *parent;
@@ -144,25 +145,25 @@ ssd_titlebar_create(struct ssd *ssd)
 
 		/* Background */
 		add_scene_rect(&subtree->parts, LAB_SSD_PART_TITLEBAR, parent,
-			width - theme->window_button_width * 2, theme->title_height,
-			theme->window_button_width, 0, color);
+			width - corner_width * 2, theme->title_height,
+			corner_width, 0, color);
 		add_scene_buffer(&subtree->parts, LAB_SSD_PART_TITLEBAR_CORNER_LEFT, parent,
 			corner_top_left, -rc.theme->border_width, -rc.theme->border_width);
 		add_scene_buffer(&subtree->parts, LAB_SSD_PART_TITLEBAR_CORNER_RIGHT, parent,
-			corner_top_right, width - theme->window_button_width,
+			corner_top_right, width - corner_width,
 			-rc.theme->border_width);
 
 		/* Buttons */
 		struct title_button *b;
-		int x = 0;
+		int x = theme->padding_width;
 		wl_list_for_each(b, &rc.title_buttons_left, link) {
 			add_button(ssd, subtree, b->type, x);
-			x += theme->window_button_width;
+			x += theme->window_button_width + theme->window_button_spacing;
 		}
 
-		x = width;
+		x = width - theme->padding_width + theme->window_button_spacing;
 		wl_list_for_each_reverse(b, &rc.title_buttons_right, link) {
-			x -= theme->window_button_width;
+			x -= theme->window_button_width + theme->window_button_spacing;
 			add_button(ssd, subtree, b->type, x);
 		}
 	} FOR_EACH_END
@@ -197,11 +198,12 @@ set_squared_corners(struct ssd *ssd, bool enable)
 {
 	struct view *view = ssd->view;
 	int width = view->current.width;
+	int corner_width = ssd_get_corner_width();
 	struct theme *theme = view->server->theme;
 
 	struct ssd_part *part;
 	struct ssd_sub_tree *subtree;
-	int x = enable ? 0 : theme->window_button_width;
+	int x = enable ? 0 : corner_width;
 
 	FOR_EACH_STATE(ssd, subtree) {
 		part = ssd_get_part(&subtree->parts, LAB_SSD_PART_TITLEBAR);
@@ -252,18 +254,23 @@ static void
 update_visible_buttons(struct ssd *ssd)
 {
 	struct view *view = ssd->view;
-	int width = view->current.width;
+	int width = view->current.width - (2 * view->server->theme->padding_width);
 	int button_width = view->server->theme->window_button_width;
+	int button_spacing = view->server->theme->window_button_spacing;
 	int button_count_left = wl_list_length(&rc.title_buttons_left);
 	int button_count_right = wl_list_length(&rc.title_buttons_right);
 
 	/* Make sure infinite loop never occurs */
 	assert(button_width > 0);
+
 	/*
 	 * The corner-left button is lastly removed as it's usually a window
 	 * menu button (or an app icon button in the future).
 	 */
-	while (width < button_width * (button_count_left + button_count_right)) {
+	while (width <
+		((button_width * (button_count_left + button_count_right)) +
+			(MAX((button_count_right - 1), 0) * button_spacing) +
+			(MAX((button_count_left - 1), 0) * button_spacing))) {
 		if (button_count_left > button_count_right) {
 			button_count_left--;
 		} else {
@@ -299,6 +306,7 @@ ssd_titlebar_update(struct ssd *ssd)
 {
 	struct view *view = ssd->view;
 	int width = view->current.width;
+	int corner_width = ssd_get_corner_width();
 	struct theme *theme = view->server->theme;
 
 	bool maximized = view->maximized == VIEW_AXIS_BOTH;
@@ -335,27 +343,29 @@ ssd_titlebar_update(struct ssd *ssd)
 	struct ssd_part *part;
 	struct ssd_sub_tree *subtree;
 	struct title_button *b;
-	int bg_offset = maximized || squared ? 0 : theme->window_button_width;
+	int bg_offset = maximized || squared ? 0 : corner_width;
 	FOR_EACH_STATE(ssd, subtree) {
 		part = ssd_get_part(&subtree->parts, LAB_SSD_PART_TITLEBAR);
 		wlr_scene_rect_set_size(
 			wlr_scene_rect_from_node(part->node),
 			width - bg_offset * 2, theme->title_height);
 
-		x = 0;
+		x = theme->padding_width;
 		wl_list_for_each(b, &rc.title_buttons_left, link) {
 			part = ssd_get_part(&subtree->parts, b->type);
 			wlr_scene_node_set_position(part->node, x, 0);
-			x += theme->window_button_width;
+			x += theme->window_button_width + theme->window_button_spacing;
 		}
 
-		x = width - theme->window_button_width;
+		x = width - corner_width;
 		part = ssd_get_part(&subtree->parts, LAB_SSD_PART_TITLEBAR_CORNER_RIGHT);
 		wlr_scene_node_set_position(part->node, x, -rc.theme->border_width);
+
+		x = width - theme->padding_width + theme->window_button_spacing;
 		wl_list_for_each_reverse(b, &rc.title_buttons_right, link) {
 			part = ssd_get_part(&subtree->parts, b->type);
+			x -= theme->window_button_width + theme->window_button_spacing;
 			wlr_scene_node_set_position(part->node, x, 0);
-			x -= theme->window_button_width;
 		}
 	} FOR_EACH_END
 	ssd_update_title(ssd);
@@ -457,19 +467,23 @@ get_title_offsets(struct ssd *ssd, int *offset_left, int *offset_right)
 {
 	struct ssd_sub_tree *subtree = &ssd->titlebar.active;
 	int button_width = ssd->view->server->theme->window_button_width;
-	*offset_left = 0;
-	*offset_right = 0;
+	int button_spacing = ssd->view->server->theme->window_button_spacing;
+	int padding_width = ssd->view->server->theme->padding_width;
+	*offset_left = padding_width;
+	*offset_right = padding_width;
 
 	struct title_button *b;
 	wl_list_for_each(b, &rc.title_buttons_left, link) {
 		struct ssd_part *part = ssd_get_part(&subtree->parts, b->type);
 		if (part->node->enabled) {
+			*offset_left += *offset_left > padding_width ? button_spacing : 0;
 			*offset_left += button_width;
 		}
 	}
 	wl_list_for_each_reverse(b, &rc.title_buttons_right, link) {
 		struct ssd_part *part = ssd_get_part(&subtree->parts, b->type);
 		if (part->node->enabled) {
+			*offset_right += *offset_right > padding_width ? button_spacing : 0;
 			*offset_right += button_width;
 		}
 	}
@@ -603,10 +617,10 @@ bool
 ssd_should_be_squared(struct ssd *ssd)
 {
 	struct view *view = ssd->view;
-	int button_width = view->server->theme->window_button_width;
+	int corner_width = ssd_get_corner_width();
 
 	return (view_is_tiled_and_notify_tiled(view)
-			|| view->current.width < button_width * 2)
+			|| view->current.width < corner_width * 2)
 		&& view->maximized != VIEW_AXIS_BOTH;
 }
 

src/ssd/ssd.c

@@ -205,6 +205,13 @@ ssd_get_margin(const struct ssd *ssd)
 	return ssd ? ssd->margin : (struct border){ 0 };
 }
 
+int
+ssd_get_corner_width(void)
+{
+	/* ensure a minimum corner width */
+	return MAX(rc.corner_radius, 5);
+}
+
 void
 ssd_update_margin(struct ssd *ssd)
 {

src/theme.c

@@ -566,7 +566,9 @@ theme_builtin(struct theme *theme, struct server *server)
 	theme->window_label_text_justify = parse_justification("Center");
 	theme->menu_title_text_justify = parse_justification("Center");
 
+	theme->padding_width = 0;
 	theme->window_button_width = 26;
+	theme->window_button_spacing = 0;
 
 	parse_hexstr("#000000",
 		theme->window_active_button_menu_unpressed_image_color);
@@ -682,6 +684,9 @@ entry(struct theme *theme, const char *key, const char *value)
 	if (match_glob(key, "border.width")) {
 		theme->border_width = atoi(value);
 	}
+	if (match_glob(key, "padding.width")) {
+		theme->padding_width = atoi(value);
+	}
 	if (match_glob(key, "padding.height")) {
 		theme->padding_height = atoi(value);
 	}
@@ -745,6 +750,9 @@ entry(struct theme *theme, const char *key, const char *value)
 			theme->window_button_width = 1;
 		}
 	}
+	if (match_glob(key, "window.button.spacing")) {
+		theme->window_button_spacing = atoi(value);
+	}
 
 	/* universal button */
 	if (match_glob(key, "window.active.button.unpressed.image.color")) {
@@ -1198,10 +1206,12 @@ out:
 static void
 create_corners(struct theme *theme)
 {
+	int corner_width = ssd_get_corner_width();
+
 	struct wlr_box box = {
 		.x = 0,
 		.y = 0,
-		.width = theme->window_button_width + theme->border_width,
+		.width = corner_width + theme->border_width,
 		.height = theme->title_height + theme->border_width,
 	};
 

src/view.c

@@ -617,8 +617,7 @@ view_adjust_size(struct view *view, int *w, int *h)
 {
 	assert(view);
 	struct view_size_hints hints = view_get_size_hints(view);
-	int min_view_width = rc.theme->window_button_width * (
-		wl_list_length(&rc.title_buttons_left) + wl_list_length(&rc.title_buttons_right));
+	int min_width = view_get_min_width();
 
 	/*
 	 * "If a base size is not provided, the minimum size is to be
@@ -641,7 +640,7 @@ view_adjust_size(struct view *view, int *w, int *h)
 	 * This is currently always the case for xdg-shell views.
 	 */
 	if (hints.min_width < 1) {
-		hints.min_width = min_view_width;
+		hints.min_width = min_width;
 	}
 	if (hints.min_height < 1) {
 		hints.min_height = LAB_MIN_VIEW_HEIGHT;
@@ -2279,6 +2278,17 @@ view_reload_ssd(struct view *view)
 	}
 }
 
+int
+view_get_min_width(void)
+{
+	int button_count_left = wl_list_length(&rc.title_buttons_left);
+	int button_count_right =  wl_list_length(&rc.title_buttons_right);
+	return (rc.theme->window_button_width * (button_count_left + button_count_right)) +
+		(rc.theme->window_button_spacing * MAX((button_count_right - 1), 0)) +
+		(rc.theme->window_button_spacing * MAX((button_count_left - 1), 0)) +
+		(2 * rc.theme->padding_width);
+}
+
 void
 view_toggle_keybinds(struct view *view)
 {

src/xwayland.c

@@ -606,15 +606,15 @@ handle_map_request(struct wl_listener *listener, void *data)
 static void
 check_natural_geometry(struct view *view)
 {
+	int min_width = view_get_min_width();
+
 	/*
 	 * Some applications (example: Thonny) don't set a reasonable
 	 * un-maximized size when started maximized. Try to detect this
 	 * and set a fallback size.
 	 */
-	int min_view_width = rc.theme->window_button_width * (
-		wl_list_length(&rc.title_buttons_left) + wl_list_length(&rc.title_buttons_right));
 	if (!view_is_floating(view)
-			&& (view->natural_geometry.width < min_view_width
+			&& (view->natural_geometry.width < min_width
 			|| view->natural_geometry.height < LAB_MIN_VIEW_HEIGHT)) {
 		view_set_fallback_natural_geometry(view);
 	}