2 * vim:ts=4:sw=4:expandtab
4 * i3 - an improved dynamic tiling window manager
5 * © 2009-2013 Michael Stapelberg and contributors (see also: LICENSE)
16 #include <cairo/cairo-xcb.h>
17 #include <pango/pangocairo.h>
22 extern xcb_connection_t *conn;
23 extern xcb_screen_t *root_screen;
25 static const i3Font *savedFont = NULL;
28 static xcb_visualtype_t *root_visual_type;
29 static double pango_font_red;
30 static double pango_font_green;
31 static double pango_font_blue;
34 * Loads a Pango font description into an i3Font structure. Returns true
35 * on success, false otherwise.
38 static bool load_pango_font(i3Font *font, const char *desc) {
39 /* Load the font description */
40 font->specific.pango_desc = pango_font_description_from_string(desc);
41 if (!font->specific.pango_desc) {
42 ELOG("Could not open font %s with Pango, fallback to X font.\n", desc);
46 LOG("Using Pango font %s, size %d\n",
47 pango_font_description_get_family(font->specific.pango_desc),
48 pango_font_description_get_size(font->specific.pango_desc) / PANGO_SCALE
51 /* We cache root_visual_type here, since you must call
52 * load_pango_font before any other pango function
53 * that would need root_visual_type */
54 root_visual_type = get_visualtype(root_screen);
56 /* Create a dummy Pango layout to compute the font height */
57 cairo_surface_t *surface = cairo_xcb_surface_create(conn, root_screen->root, root_visual_type, 1, 1);
58 cairo_t *cr = cairo_create(surface);
59 PangoLayout *layout = pango_cairo_create_layout(cr);
60 pango_layout_set_font_description(layout, font->specific.pango_desc);
62 /* Get the font height */
64 pango_layout_get_pixel_size(layout, NULL, &height);
65 font->height = height;
68 g_object_unref(layout);
70 cairo_surface_destroy(surface);
72 /* Set the font type and return successfully */
73 font->type = FONT_TYPE_PANGO;
78 * Draws text using Pango rendering.
81 static void draw_text_pango(const char *text, size_t text_len,
82 xcb_drawable_t drawable, int x, int y, int max_width) {
83 /* Create the Pango layout */
84 /* root_visual_type is cached in load_pango_font */
85 cairo_surface_t *surface = cairo_xcb_surface_create(conn, drawable,
86 root_visual_type, x + max_width, y + savedFont->height);
87 cairo_t *cr = cairo_create(surface);
88 PangoLayout *layout = pango_cairo_create_layout(cr);
91 pango_layout_set_font_description(layout, savedFont->specific.pango_desc);
92 pango_layout_set_width(layout, max_width * PANGO_SCALE);
93 pango_layout_set_wrap(layout, PANGO_WRAP_CHAR);
94 pango_layout_set_ellipsize(layout, PANGO_ELLIPSIZE_END);
96 pango_layout_set_text(layout, text, text_len);
99 cairo_set_source_rgb(cr, pango_font_red, pango_font_green, pango_font_blue);
100 pango_cairo_update_layout(cr, layout);
101 pango_layout_get_pixel_size(layout, NULL, &height);
102 cairo_move_to(cr, x, y - (height - savedFont->height));
103 pango_cairo_show_layout(cr, layout);
106 g_object_unref(layout);
108 cairo_surface_destroy(surface);
112 * Calculate the text width using Pango rendering.
115 static int predict_text_width_pango(const char *text, size_t text_len) {
116 /* Create a dummy Pango layout */
117 /* root_visual_type is cached in load_pango_font */
118 cairo_surface_t *surface = cairo_xcb_surface_create(conn, root_screen->root, root_visual_type, 1, 1);
119 cairo_t *cr = cairo_create(surface);
120 PangoLayout *layout = pango_cairo_create_layout(cr);
122 /* Get the font width */
124 pango_layout_set_font_description(layout, savedFont->specific.pango_desc);
125 pango_layout_set_text(layout, text, text_len);
126 pango_cairo_update_layout(cr, layout);
127 pango_layout_get_pixel_size(layout, &width, NULL);
130 g_object_unref(layout);
132 cairo_surface_destroy(surface);
139 * Loads a font for usage, also getting its metrics. If fallback is true,
140 * the fonts 'fixed' or '-misc-*' will be loaded instead of exiting.
143 i3Font load_font(const char *pattern, const bool fallback) {
145 font.type = FONT_TYPE_NONE;
148 /* Try to load a pango font if specified */
149 if (strlen(pattern) > strlen("pango:") && !strncmp(pattern, "pango:", strlen("pango:"))) {
150 const char *font_pattern = pattern + strlen("pango:");
151 if (load_pango_font(&font, font_pattern)) {
152 font.pattern = sstrdup(pattern);
155 } else if (strlen(pattern) > strlen("xft:") && !strncmp(pattern, "xft:", strlen("xft:"))) {
156 const char *font_pattern = pattern + strlen("xft:");
157 if (load_pango_font(&font, font_pattern)) {
158 font.pattern = sstrdup(pattern);
164 /* Send all our requests first */
165 font.specific.xcb.id = xcb_generate_id(conn);
166 xcb_void_cookie_t font_cookie = xcb_open_font_checked(conn, font.specific.xcb.id,
167 strlen(pattern), pattern);
168 xcb_query_font_cookie_t info_cookie = xcb_query_font(conn, font.specific.xcb.id);
170 /* Check for errors. If errors, fall back to default font. */
171 xcb_generic_error_t *error;
172 error = xcb_request_check(conn, font_cookie);
174 /* If we fail to open font, fall back to 'fixed' */
175 if (fallback && error != NULL) {
176 ELOG("Could not open font %s (X error %d). Trying fallback to 'fixed'.\n",
177 pattern, error->error_code);
179 font_cookie = xcb_open_font_checked(conn, font.specific.xcb.id,
180 strlen(pattern), pattern);
181 info_cookie = xcb_query_font(conn, font.specific.xcb.id);
183 /* Check if we managed to open 'fixed' */
184 error = xcb_request_check(conn, font_cookie);
186 /* Fall back to '-misc-*' if opening 'fixed' fails. */
188 ELOG("Could not open fallback font 'fixed', trying with '-misc-*'.\n");
190 font_cookie = xcb_open_font_checked(conn, font.specific.xcb.id,
191 strlen(pattern), pattern);
192 info_cookie = xcb_query_font(conn, font.specific.xcb.id);
194 if ((error = xcb_request_check(conn, font_cookie)) != NULL)
195 errx(EXIT_FAILURE, "Could open neither requested font nor fallbacks "
196 "(fixed or -misc-*): X11 error %d", error->error_code);
200 font.pattern = sstrdup(pattern);
201 LOG("Using X font %s\n", pattern);
203 /* Get information (height/name) for this font */
204 if (!(font.specific.xcb.info = xcb_query_font_reply(conn, info_cookie, NULL)))
205 errx(EXIT_FAILURE, "Could not load font \"%s\"", pattern);
207 /* Get the font table, if possible */
208 if (xcb_query_font_char_infos_length(font.specific.xcb.info) == 0)
209 font.specific.xcb.table = NULL;
211 font.specific.xcb.table = xcb_query_font_char_infos(font.specific.xcb.info);
213 /* Calculate the font height */
214 font.height = font.specific.xcb.info->font_ascent + font.specific.xcb.info->font_descent;
216 /* Set the font type and return successfully */
217 font.type = FONT_TYPE_XCB;
222 * Defines the font to be used for the forthcoming calls.
225 void set_font(i3Font *font) {
230 * Frees the resources taken by the current font.
233 void free_font(void) {
234 free(savedFont->pattern);
235 switch (savedFont->type) {
239 case FONT_TYPE_XCB: {
240 /* Close the font and free the info */
241 xcb_close_font(conn, savedFont->specific.xcb.id);
242 if (savedFont->specific.xcb.info)
243 free(savedFont->specific.xcb.info);
247 case FONT_TYPE_PANGO:
248 /* Free the font description */
249 pango_font_description_free(savedFont->specific.pango_desc);
259 * Defines the colors to be used for the forthcoming draw_text calls.
262 void set_font_colors(xcb_gcontext_t gc, uint32_t foreground, uint32_t background) {
263 assert(savedFont != NULL);
265 switch (savedFont->type) {
269 case FONT_TYPE_XCB: {
270 /* Change the font and colors in the GC */
271 uint32_t mask = XCB_GC_FOREGROUND | XCB_GC_BACKGROUND | XCB_GC_FONT;
272 uint32_t values[] = { foreground, background, savedFont->specific.xcb.id };
273 xcb_change_gc(conn, gc, mask, values);
277 case FONT_TYPE_PANGO:
278 /* Save the foreground font */
279 pango_font_red = ((foreground >> 16) & 0xff) / 255.0;
280 pango_font_green = ((foreground >> 8) & 0xff) / 255.0;
281 pango_font_blue = (foreground & 0xff) / 255.0;
290 static int predict_text_width_xcb(const xcb_char2b_t *text, size_t text_len);
292 static void draw_text_xcb(const xcb_char2b_t *text, size_t text_len, xcb_drawable_t drawable,
293 xcb_gcontext_t gc, int x, int y, int max_width) {
294 /* X11 coordinates for fonts start at the baseline */
295 int pos_y = y + savedFont->specific.xcb.info->font_ascent;
297 /* The X11 protocol limits text drawing to 255 chars, so we may need
301 /* Calculate the size of this chunk */
302 int chunk_size = (text_len > 255 ? 255 : text_len);
303 const xcb_char2b_t *chunk = text + offset;
306 xcb_image_text_16(conn, chunk_size, drawable, gc, x, pos_y, chunk);
308 /* Advance the offset and length of the text to draw */
309 offset += chunk_size;
310 text_len -= chunk_size;
312 /* Check if we're done */
316 /* Advance pos_x based on the predicted text width */
317 x += predict_text_width_xcb(chunk, chunk_size);
322 * Draws text onto the specified X drawable (normally a pixmap) at the
323 * specified coordinates (from the top left corner of the leftmost, uppermost
324 * glyph) and using the provided gc.
326 * Text must be specified as an i3String.
329 void draw_text(i3String *text, xcb_drawable_t drawable,
330 xcb_gcontext_t gc, int x, int y, int max_width) {
331 assert(savedFont != NULL);
333 switch (savedFont->type) {
338 draw_text_xcb(i3string_as_ucs2(text), i3string_get_num_glyphs(text),
339 drawable, gc, x, y, max_width);
342 case FONT_TYPE_PANGO:
343 /* Render the text using Pango */
344 draw_text_pango(i3string_as_utf8(text), i3string_get_num_bytes(text),
345 drawable, x, y, max_width);
354 * ASCII version of draw_text to print static strings.
357 void draw_text_ascii(const char *text, xcb_drawable_t drawable,
358 xcb_gcontext_t gc, int x, int y, int max_width) {
359 assert(savedFont != NULL);
361 switch (savedFont->type) {
367 size_t text_len = strlen(text);
368 if (text_len > 255) {
369 /* The text is too long to draw it directly to X */
370 i3String *str = i3string_from_utf8(text);
371 draw_text(str, drawable, gc, x, y, max_width);
374 /* X11 coordinates for fonts start at the baseline */
375 int pos_y = y + savedFont->specific.xcb.info->font_ascent;
377 xcb_image_text_8(conn, text_len, drawable, gc, x, pos_y, text);
382 case FONT_TYPE_PANGO:
383 /* Render the text using Pango */
384 draw_text_pango(text, strlen(text),
385 drawable, x, y, max_width);
393 static int xcb_query_text_width(const xcb_char2b_t *text, size_t text_len) {
394 /* Make the user know we’re using the slow path, but only once. */
395 static bool first_invocation = true;
396 if (first_invocation) {
397 fprintf(stderr, "Using slow code path for text extents\n");
398 first_invocation = false;
401 /* Query the text width */
402 xcb_generic_error_t *error;
403 xcb_query_text_extents_cookie_t cookie = xcb_query_text_extents(conn,
404 savedFont->specific.xcb.id, text_len, (xcb_char2b_t*)text);
405 xcb_query_text_extents_reply_t *reply = xcb_query_text_extents_reply(conn,
408 /* We return a safe estimate because a rendering error is better than
409 * a crash. Plus, the user will see the error in his log. */
410 fprintf(stderr, "Could not get text extents (X error code %d)\n",
412 return savedFont->specific.xcb.info->max_bounds.character_width * text_len;
415 int width = reply->overall_width;
420 static int predict_text_width_xcb(const xcb_char2b_t *input, size_t text_len) {
425 if (savedFont->specific.xcb.table == NULL) {
426 /* If we don't have a font table, fall back to querying the server */
427 width = xcb_query_text_width(input, text_len);
429 /* Save some pointers for convenience */
430 xcb_query_font_reply_t *font_info = savedFont->specific.xcb.info;
431 xcb_charinfo_t *font_table = savedFont->specific.xcb.table;
433 /* Calculate the width using the font table */
435 for (size_t i = 0; i < text_len; i++) {
436 xcb_charinfo_t *info;
437 int row = input[i].byte1;
438 int col = input[i].byte2;
440 if (row < font_info->min_byte1 ||
441 row > font_info->max_byte1 ||
442 col < font_info->min_char_or_byte2 ||
443 col > font_info->max_char_or_byte2)
446 /* Don't you ask me, how this one works… (Merovius) */
447 info = &font_table[((row - font_info->min_byte1) *
448 (font_info->max_char_or_byte2 - font_info->min_char_or_byte2 + 1)) +
449 (col - font_info->min_char_or_byte2)];
451 if (info->character_width != 0 ||
452 (info->right_side_bearing |
453 info->left_side_bearing |
455 info->descent) != 0) {
456 width += info->character_width;
465 * Predict the text width in pixels for the given text. Text must be
466 * specified as an i3String.
469 int predict_text_width(i3String *text) {
470 assert(savedFont != NULL);
472 switch (savedFont->type) {
477 return predict_text_width_xcb(i3string_as_ucs2(text), i3string_get_num_glyphs(text));
479 case FONT_TYPE_PANGO:
480 /* Calculate extents using Pango */
481 return predict_text_width_pango(i3string_as_utf8(text), i3string_get_num_bytes(text));