Don't use title content in size calculations

Make height configurable instead

This prevents distracting screen flashing and seems to work fine
for larger glyphs as well (Tested with Japanese).

squashed: Free layout and buffer
squashed: pass in markup information

common/pango.c

@@ -82,6 +82,40 @@ PangoLayout *get_pango_layout(cairo_t *cairo, const char *font,
 	return layout;
 }
 
+void get_text_physical_size(cairo_t *cairo, const char *font, int* ascent, int* descent,
+		int* ink_size, bool markup, const char *fmt, ...) {
+	va_list args;
+	va_start(args, fmt);
+	// Add one since vsnprintf excludes null terminator.
+	int length = vsnprintf(NULL, 0, fmt, args) + 1;
+	va_end(args);
+
+	char *buf = malloc(length);
+	if (buf == NULL) {
+		sway_log(SWAY_ERROR, "Failed to allocate memory");
+		return;
+	}
+	va_start(args, fmt);
+	vsnprintf(buf, length, fmt, args);
+	va_end(args);
+
+	PangoLayout *layout = get_pango_layout(cairo, font, buf, 1, markup);
+	pango_cairo_update_layout(cairo, layout);
+	PangoRectangle ir, lr;
+	pango_layout_get_pixel_extents(layout, &ir, &lr);
+	if (ascent) {
+		*ascent = PANGO_ASCENT(ir);
+	}
+	if (descent) {
+		*descent = PANGO_DESCENT(ir);
+	}
+	if (ink_size) {
+		*ink_size = ir.height;
+	}
+	g_object_unref(layout);
+	free(buf);
+}
+
 void get_text_size(cairo_t *cairo, const char *font, int *width, int *height,
 		int *baseline, double scale, bool markup, const char *fmt, ...) {
 	va_list args;

include/pango.h

@@ -15,6 +15,8 @@
 size_t escape_markup_text(const char *src, char *dest);
 PangoLayout *get_pango_layout(cairo_t *cairo, const char *font,
 		const char *text, double scale, bool markup);
+void get_text_physical_size(cairo_t *cairo, const char *font, int *ascent, int* descent,
+		int *ink_size, bool markup, const char *fmt, ...);
 void get_text_size(cairo_t *cairo, const char *font, int *width, int *height,
 		int *baseline, double scale, bool markup, const char *fmt, ...);
 void pango_printf(cairo_t *cairo, const char *font,

include/sway/commands.h

@@ -187,6 +187,7 @@ sway_cmd cmd_tiling_drag_threshold;
 sway_cmd cmd_title_align;
 sway_cmd cmd_title_format;
 sway_cmd cmd_titlebar_border_thickness;
+sway_cmd cmd_titlebar_max_text_height;
 sway_cmd cmd_titlebar_padding;
 sway_cmd cmd_unbindcode;
 sway_cmd cmd_unbindswitch;

include/sway/config.h

@@ -480,10 +480,9 @@ struct sway_config {
 	enum sway_container_layout default_orientation;
 	enum sway_container_layout default_layout;
 	char *font;
-	size_t font_height;
-	size_t font_baseline;
 	bool pango_markup;
 	int titlebar_border_thickness;
+	int titlebar_max_text_height;
 	int titlebar_h_padding;
 	int titlebar_v_padding;
 	size_t urgent_timeout;
@@ -689,16 +688,6 @@ void free_bar_binding(struct bar_binding *binding);
 
 void free_workspace_config(struct workspace_config *wsc);
 
-/**
- * Updates the value of config->font_height based on the max title height
- * reported by each container. If recalculate is true, the containers will
- * recalculate their heights before reporting.
- *
- * If the height has changed, all containers will be rearranged to take on the
- * new size.
- */
-void config_update_font_height(bool recalculate);
-
 /**
  * Convert bindsym into bindcode using the first configured layout.
  * Return false in case the conversion is unsuccessful.

include/sway/tree/container.h

@@ -142,7 +142,7 @@ struct sway_container {
 	struct wlr_texture *title_unfocused;
 	struct wlr_texture *title_urgent;
 	size_t title_height;
-	size_t title_baseline;
+	int title_ascent;
 
 	list_t *marks; // char *
 	struct wlr_texture *marks_focused;

sway/commands.c

@@ -89,6 +89,7 @@ static struct cmd_handler handlers[] = {
 	{ "tiling_drag_threshold", cmd_tiling_drag_threshold },
 	{ "title_align", cmd_title_align },
 	{ "titlebar_border_thickness", cmd_titlebar_border_thickness },
+	{ "titlebar_max_text_height", cmd_titlebar_max_text_height },
 	{ "titlebar_padding", cmd_titlebar_padding },
 	{ "unbindcode", cmd_unbindcode },
 	{ "unbindswitch", cmd_unbindswitch },

sway/commands/font.c

@@ -22,6 +22,5 @@ struct cmd_results *cmd_font(int argc, char **argv) {
 	}
 
 	free(font);
-	config_update_font_height(true);
 	return cmd_results_new(CMD_SUCCESS, NULL);
 }

sway/commands/reload.c

@@ -48,7 +48,6 @@ static void do_reload(void *data) {
 	}
 	list_free_items_and_destroy(bar_ids);
 
-	config_update_font_height(true);
 	root_for_each_container(rebuild_textures_iterator, NULL);
 
 	arrange_root();

sway/commands/title_format.c

@@ -23,6 +23,5 @@ struct cmd_results *cmd_title_format(int argc, char **argv) {
 	}
 	view->title_format = format;
 	view_update_title(view, true);
-	config_update_font_height(true);
 	return cmd_results_new(CMD_SUCCESS, NULL);
 }

sway/commands/titlebar_max_text_height.c

@@ -0,0 +1,29 @@
+#include <string.h>
+#include "sway/commands.h"
+#include "sway/config.h"
+#include "sway/output.h"
+#include "sway/tree/arrange.h"
+#include "log.h"
+
+struct cmd_results *cmd_titlebar_max_text_height(int argc, char **argv) {
+	struct cmd_results *error = NULL;
+	if ((error = checkarg(argc, "titlebar_max_text_height", EXPECTED_EQUAL_TO, 1))) {
+		return error;
+	}
+
+	char *inv;
+	int value = strtol(argv[0], &inv, 10);
+	if (*inv != '\0' || value < 0) {
+		return cmd_results_new(CMD_FAILURE, "Invalid size specified");
+	}
+
+	config->titlebar_max_text_height = value;
+
+	for (int i = 0; i < root->outputs->length; ++i) {
+		struct sway_output *output = root->outputs->items[i];
+		arrange_workspace(output_get_active_workspace(output));
+		output_damage_whole(output);
+	}
+
+	return cmd_results_new(CMD_SUCCESS, NULL);
+}

sway/config.c

@@ -236,13 +236,14 @@ static void config_defaults(struct sway_config *config) {
 	config->default_layout = L_NONE;
 	config->default_orientation = L_NONE;
 	if (!(config->font = strdup("monospace 10"))) goto cleanup;
-	config->font_height = 17; // height of monospace 10
 	config->urgent_timeout = 500;
 	config->focus_on_window_activation = FOWA_URGENT;
 	config->popup_during_fullscreen = POPUP_SMART;
 	config->xwayland = XWAYLAND_MODE_LAZY;
 
+	config->titlebar_max_text_height = 17; // height of monospace 10
 	config->titlebar_border_thickness = 1;
+
 	config->titlebar_h_padding = 5;
 	config->titlebar_v_padding = 4;
 
@@ -960,37 +961,6 @@ int workspace_output_cmp_workspace(const void *a, const void *b) {
 	return lenient_strcmp(wsa->workspace, wsb->workspace);
 }
 
-static void find_font_height_iterator(struct sway_container *con, void *data) {
-	size_t amount_below_baseline = con->title_height - con->title_baseline;
-	size_t extended_height = config->font_baseline + amount_below_baseline;
-	if (extended_height > config->font_height) {
-		config->font_height = extended_height;
-	}
-}
-
-static void find_baseline_iterator(struct sway_container *con, void *data) {
-	bool *recalculate = data;
-	if (*recalculate) {
-		container_calculate_title_height(con);
-	}
-	if (con->title_baseline > config->font_baseline) {
-		config->font_baseline = con->title_baseline;
-	}
-}
-
-void config_update_font_height(bool recalculate) {
-	size_t prev_max_height = config->font_height;
-	config->font_height = 0;
-	config->font_baseline = 0;
-
-	root_for_each_container(find_baseline_iterator, &recalculate);
-	root_for_each_container(find_font_height_iterator, NULL);
-
-	if (config->font_height != prev_max_height) {
-		arrange_root();
-	}
-}
-
 static void translate_binding_list(list_t *bindings, list_t *bindsyms,
 		list_t *bindcodes) {
 	for (int i = 0; i < bindings->length; ++i) {

sway/desktop/render.c

@@ -468,7 +468,7 @@ static void render_titlebar(struct sway_output *output,
 	int ob_inner_width = scale_length(inner_width, inner_x, output_scale);
 	int ob_bg_height = scale_length(
 			(titlebar_v_padding - titlebar_border_thickness) * 2 +
-			config->font_height, bg_y, output_scale);
+			config->titlebar_max_text_height, bg_y, output_scale);
 
 	// Marks
 	int ob_marks_x = 0; // output-buffer-local
@@ -479,11 +479,11 @@ static void render_titlebar(struct sway_output *output,
 			&texture_box.width, &texture_box.height);
 		ob_marks_width = texture_box.width;
 
-		// The marks texture might be shorter than the config->font_height, in
+		// The marks texture might be shorter than config->titlebar_max_text_height, in
 		// which case we need to pad it as evenly as possible above and below.
 		int ob_padding_total = ob_bg_height - texture_box.height;
 		int ob_padding_above = floor(ob_padding_total / 2.0);
-		int ob_padding_below = ceil(ob_padding_total / 2.0);
+		int ob_padding_below = ob_padding_total - ob_padding_above;
 
 		// Render texture. If the title is on the right, the marks will be on
 		// the left. Otherwise, they will be on the right.
@@ -532,13 +532,11 @@ static void render_titlebar(struct sway_output *output,
 			&texture_box.width, &texture_box.height);
 		ob_title_width = texture_box.width;
 
-		// The title texture might be shorter than the config->font_height,
+		// The title texture might be shorter than config->titlebar_max_text_height,
 		// in which case we need to pad it above and below.
-		int ob_padding_above = round((config->font_baseline -
-					con->title_baseline + titlebar_v_padding -
-					titlebar_border_thickness) * output_scale);
-		int ob_padding_below = ob_bg_height - ob_padding_above -
-			texture_box.height;
+		int ob_padding_total = fmax(0, (ob_bg_height - con->title_height));
+		int ob_padding_above = floor(ob_padding_total / 2.0);
+		int ob_padding_below = ob_padding_total - ob_padding_above;
 
 		// Render texture
 		if (texture_box.width > ob_inner_width - ob_marks_width) {
@@ -630,7 +628,7 @@ static void render_titlebar(struct sway_output *output,
 	box.y = y + titlebar_border_thickness;
 	box.width = titlebar_h_padding - titlebar_border_thickness;
 	box.height = (titlebar_v_padding - titlebar_border_thickness) * 2 +
-		config->font_height;
+		config->titlebar_max_text_height;
 	scale_box(&box, output_scale);
 	int left_x = ob_left_x + round(output_x * output_scale);
 	if (box.x + box.width < left_x) {
@@ -643,7 +641,7 @@ static void render_titlebar(struct sway_output *output,
 	box.y = y + titlebar_border_thickness;
 	box.width = titlebar_h_padding - titlebar_border_thickness;
 	box.height = (titlebar_v_padding - titlebar_border_thickness) * 2 +
-		config->font_height;
+		config->titlebar_max_text_height;
 	scale_box(&box, output_scale);
 	int right_rx = ob_right_x + ob_right_width + round(output_x * output_scale);
 	if (right_rx < box.x) {

sway/meson.build

@@ -111,6 +111,7 @@ sway_sources = files(
 	'commands/title_align.c',
 	'commands/title_format.c',
 	'commands/titlebar_border_thickness.c',
+	'commands/titlebar_max_text_height.c',
 	'commands/titlebar_padding.c',
 	'commands/unmark.c',
 	'commands/urgent.c',

sway/tree/container.c

@@ -33,6 +33,7 @@ struct sway_container *container_create(struct sway_view *view) {
 	c->layout = L_NONE;
 	c->view = view;
 	c->alpha = 1.0f;
+	c->title_ascent = 0;
 
 	if (!view) {
 		c->children = create_list();
@@ -497,7 +498,7 @@ static void update_title_texture(struct sway_container *con,
 	PangoContext *pango = pango_cairo_create_context(cairo);
 	cairo_set_source_rgba(cairo, class->text[0], class->text[1],
 			class->text[2], class->text[3]);
-	cairo_move_to(cairo, 0, 0);
+	cairo_move_to(cairo, 0, con->title_ascent);
 
 	pango_printf(cairo, config->font, scale, config->pango_markup,
 			"%s", con->formatted_title);
@@ -532,13 +533,14 @@ void container_calculate_title_height(struct sway_container *container) {
 		return;
 	}
 	cairo_t *cairo = cairo_create(NULL);
-	int height;
-	int baseline;
-	get_text_size(cairo, config->font, NULL, &height, &baseline, 1,
-			config->pango_markup, "%s", container->formatted_title);
+	int ink_size, ascent;
+	get_text_physical_size(cairo, config->font, &ascent, NULL,
+			&ink_size, config->pango_markup, "%s",
+			container->formatted_title);
+
 	cairo_destroy(cairo);
-	container->title_height = height;
-	container->title_baseline = baseline;
+	container->title_height = ink_size;
+	container->title_ascent = ascent;
 }
 
 /**
@@ -617,7 +619,7 @@ void container_update_representation(struct sway_container *con) {
 }
 
 size_t container_titlebar_height(void) {
-	return config->font_height + config->titlebar_v_padding * 2;
+	return config->titlebar_max_text_height + config->titlebar_v_padding * 2;
 }
 
 void floating_calculate_constraints(int *min_width, int *max_width,

sway/tree/view.c

@@ -1214,7 +1214,6 @@ void view_update_title(struct sway_view *view, bool force) {
 		view->container->formatted_title = NULL;
 	}
 	container_calculate_title_height(view->container);
-	config_update_font_height(false);
 
 	// Update title after the global font height is updated
 	container_update_title_textures(view->container);