绘制 tag 标识

src/renderer/text.c

@@ -1,4 +1,6 @@
+#include <cairo.h>
 #include <glib-object.h>
+#include <glib.h>
 #include <pango/pango-attributes.h>
 #include <pango/pango-context.h>
 #include <pango/pango-font.h>
@@ -6,12 +8,16 @@
 #include <pango/pango-layout.h>
 #include <pango/pango-types.h>
 #include <pango/pangocairo.h>
+#include <stdbool.h>
 #include <stdint.h>
 #include <stdio.h>
 
 #include "renderer.h"
+#include "types.h"
 
 static PangoContext *context = NULL;
+static PangoAttrList *attr_list = NULL;
+static PangoLayout *layout = NULL;
 
 uint32_t get_font_height(const char *font_family, const uint32_t font_size,
                          const uint32_t dpi) {
@@ -22,14 +28,13 @@ uint32_t get_font_height(const char *font_family, const uint32_t font_size,
 
   pango_cairo_context_set_resolution(context, dpi);
   PangoLanguage *lang = pango_context_get_language(context);
-  PangoAttrList *attr_list = pango_attr_list_new();
+  attr_list = pango_attr_list_new();
 
   PangoFontDescription *desc = pango_font_description_from_string(font_family);
   pango_font_description_set_size(desc, font_size * PANGO_SCALE);
 
   PangoAttribute *attr = pango_attr_font_desc_new(desc);
   pango_attr_list_insert(attr_list, attr);
-  pango_attr_list_unref(attr_list);
 
   PangoFontMetrics *metrics = pango_context_get_metrics(context, desc, lang);
   int ascent = pango_font_metrics_get_ascent(metrics);
@@ -43,9 +48,108 @@ uint32_t get_font_height(const char *font_family, const uint32_t font_size,
   return font_height;
 }
 
+static void draw_background(cairo_t *cr, color_t *color, int32_t x, int32_t y,
+                            uint32_t width, uint32_t height) {
+  cairo_move_to(cr, x, y);
+  cairo_set_source_rgba(cr, color->red, color->green, color->blue,
+                        color->alpha);
+  cairo_rectangle(cr, x, y, width, height);
+  cairo_fill(cr);
+}
+
+static void prepare_layout(bool align_center) {
+  if (!layout) {
+    layout = pango_layout_new(context);
+    pango_layout_set_attributes(layout, attr_list);
+    pango_layout_set_wrap(layout, PANGO_WRAP_NONE);
+    pango_layout_set_ellipsize(layout, PANGO_ELLIPSIZE_END);
+  }
+
+  PangoAlignment align = align_center ? PANGO_ALIGN_CENTER : PANGO_ALIGN_LEFT;
+  pango_layout_set_alignment(layout, align);
+}
+
+static void get_layout_size(PangoLayout *layout, int *width, int *height) {
+  PangoRectangle ink_rect, logical_rect;
+  pango_layout_get_pixel_extents(layout, &ink_rect, &logical_rect);
+
+  int w = MAX(ink_rect.width, logical_rect.width);
+  int h = MAX(ink_rect.height, logical_rect.height);
+  if (width) *width = w;
+  if (height) *height = h;
+}
+
+static uint32_t get_text_width(const char *text) {
+  prepare_layout(false);
+  pango_layout_set_width(layout, -1);
+  pango_layout_set_text(layout, text, -1);
+  int w;
+  get_layout_size(layout, &w, NULL);
+  return (uint32_t)w;
+}
+
+static void draw_text(cairo_t *cr, const char *text, color_t *color, int32_t x,
+                      uint32_t y, uint32_t width, uint32_t height,
+                      bool align_center) {
+  prepare_layout(align_center);
+  pango_layout_set_width(layout, width * PANGO_SCALE);
+  pango_layout_set_text(layout, text, -1);
+  cairo_set_source_rgba(cr, color->red, color->green, color->blue,
+                        color->alpha);
+  int h = 0;
+  get_layout_size(layout, NULL, &h);
+  double ty = ((double)height - h) / 2;
+
+  pango_cairo_update_layout(cr, layout);
+  cairo_move_to(cr, x, y + ty);
+  pango_cairo_show_layout(cr, layout);
+}
+
+static void clean_cairo_context(cairo_t *cr) {
+  cairo_save(cr);
+  cairo_set_operator(cr, CAIRO_OPERATOR_CLEAR);
+  cairo_paint(cr);
+  cairo_restore(cr);
+}
+
+void draw_bar(monitor_t *monitor, bool is_current_monitor,
+              color_set_t *color_set, uint32_t height, uint32_t tag_x_padding) {
+  cairo_t *cr = monitor->cr;
+  int32_t x = 0;
+  uint32_t width = 0;
+  const char *text;
+  color_t *color;
+
+  clean_cairo_context(cr);
+  draw_background(cr, &color_set->bar_bg, 0, 0, monitor->monitor_width, height);
+
+  /* 绘制 tags */
+  for (int i = 0; i < g_strv_length(monitor->tags); i++) {
+    bool selected = (monitor->selected_tag >> i) & 0x1;
+    text = monitor->tags[i];
+    width = get_text_width(text) + tag_x_padding * 2;
+
+    color = selected ? &color_set->active_tag_bg : &color_set->tag_bg;
+    if (color->rgba != color_set->bar_bg.rgba) {
+      draw_background(cr, color, x, 0, width, height);
+    }
+    color = selected ? &color_set->active_tag_color : &color_set->tag_color;
+    draw_text(cr, text, color, x, 0, width, height, true);
+    x += width;
+  }
+}
+
 void clean_pango_context(void) {
-  if (!context) return;
-
-  g_object_unref(context);
-  context = NULL;
+  if (layout) {
+    g_object_unref(layout);
+    layout = NULL;
+  }
+  if (attr_list) {
+    pango_attr_list_unref(attr_list);
+    attr_list = NULL;
+  }
+  if (context) {
+    g_object_unref(context);
+    context = NULL;
+  }
 }