Use fixed titlebar heights

Use fixed titlebar heights. The default height is calculated based on
font metrics for the configured font and current locale.

Some testing with titles with emoji and CJK characters (which are
substantially higher in my setup) shows that the titlebars retain their
initial value, text does shift up or down, and all titlebars always
remain aligned.

Also drop some also now-unecessary title_height calculations.

Makes also needed to be updated, since they should be positioned with
the same rules.

1 files changed, 18 insertions, 0 deletions

diff --git a/common/pango.c b/common/pango.c
index dbc369dc..88932203 100644
--- a/common/pango.c
+++ b/common/pango.c
@@ -109,6 +109,24 @@ void get_text_size(cairo_t *cairo, const char *font, int *width, int *height,
 	free(buf);
 }
 
+void get_text_metrics(const char *font, int *height, int *baseline) {
+	cairo_t *cairo = cairo_create(NULL);
+	PangoContext *pango = pango_cairo_create_context(cairo);
+	PangoFontDescription *description = pango_font_description_from_string(font);
+	PangoFontMetrics *metrics;
+
+	// When passing NULL as a language, pango uses the current locale.
+	metrics = pango_context_get_metrics(pango, description, NULL);
+
+	*baseline = pango_font_metrics_get_ascent(metrics) / PANGO_SCALE;
+	*height = *baseline + pango_font_metrics_get_descent(metrics) / PANGO_SCALE;
+
+	pango_font_metrics_unref(metrics);
+	pango_font_description_free(description);
+	g_object_unref(pango);
+	cairo_destroy(cairo);
+}
+
 void pango_printf(cairo_t *cairo, const char *font,
 		double scale, bool markup, const char *fmt, ...) {
 	va_list args;