248 lines
8.1 KiB
C
248 lines
8.1 KiB
C
/*
|
||
* vim:ts=4:sw=4:expandtab
|
||
*
|
||
* i3 - an improved dynamic tiling window manager
|
||
* © 2009-2011 Michael Stapelberg and contributors (see also: LICENSE)
|
||
*
|
||
*/
|
||
#include <assert.h>
|
||
#include <stdint.h>
|
||
#include <stdlib.h>
|
||
#include <string.h>
|
||
#include <stdbool.h>
|
||
#include <err.h>
|
||
|
||
#include "libi3.h"
|
||
|
||
extern xcb_connection_t *conn;
|
||
static const i3Font *savedFont = NULL;
|
||
|
||
/*
|
||
* Loads a font for usage, also getting its metrics. If fallback is true,
|
||
* the fonts 'fixed' or '-misc-*' will be loaded instead of exiting.
|
||
*
|
||
*/
|
||
i3Font load_font(const char *pattern, const bool fallback) {
|
||
i3Font font;
|
||
|
||
/* Send all our requests first */
|
||
font.id = xcb_generate_id(conn);
|
||
xcb_void_cookie_t font_cookie = xcb_open_font_checked(conn, font.id,
|
||
strlen(pattern), pattern);
|
||
xcb_query_font_cookie_t info_cookie = xcb_query_font(conn, font.id);
|
||
|
||
/* Check for errors. If errors, fall back to default font. */
|
||
xcb_generic_error_t *error;
|
||
error = xcb_request_check(conn, font_cookie);
|
||
|
||
/* If we fail to open font, fall back to 'fixed' */
|
||
if (fallback && error != NULL) {
|
||
ELOG("Could not open font %s (X error %d). Trying fallback to 'fixed'.\n",
|
||
pattern, error->error_code);
|
||
pattern = "fixed";
|
||
font_cookie = xcb_open_font_checked(conn, font.id, strlen(pattern), pattern);
|
||
info_cookie = xcb_query_font(conn, font.id);
|
||
|
||
/* Check if we managed to open 'fixed' */
|
||
error = xcb_request_check(conn, font_cookie);
|
||
|
||
/* Fall back to '-misc-*' if opening 'fixed' fails. */
|
||
if (error != NULL) {
|
||
ELOG("Could not open fallback font 'fixed', trying with '-misc-*'.\n");
|
||
pattern = "-misc-*";
|
||
font_cookie = xcb_open_font_checked(conn, font.id, strlen(pattern), pattern);
|
||
info_cookie = xcb_query_font(conn, font.id);
|
||
|
||
if ((error = xcb_request_check(conn, font_cookie)) != NULL)
|
||
errx(EXIT_FAILURE, "Could open neither requested font nor fallbacks "
|
||
"(fixed or -misc-*): X11 error %d", error->error_code);
|
||
}
|
||
}
|
||
|
||
/* Get information (height/name) for this font */
|
||
if (!(font.info = xcb_query_font_reply(conn, info_cookie, NULL)))
|
||
errx(EXIT_FAILURE, "Could not load font \"%s\"", pattern);
|
||
|
||
/* Get the font table, if possible */
|
||
if (xcb_query_font_char_infos_length(font.info) == 0)
|
||
font.table = NULL;
|
||
else
|
||
font.table = xcb_query_font_char_infos(font.info);
|
||
|
||
/* Calculate the font height */
|
||
font.height = font.info->font_ascent + font.info->font_descent;
|
||
|
||
return font;
|
||
}
|
||
|
||
/*
|
||
* Defines the font to be used for the forthcoming calls.
|
||
*
|
||
*/
|
||
void set_font(i3Font *font) {
|
||
savedFont = font;
|
||
}
|
||
|
||
/*
|
||
* Frees the resources taken by the current font.
|
||
*
|
||
*/
|
||
void free_font(void) {
|
||
/* Close the font and free the info */
|
||
xcb_close_font(conn, savedFont->id);
|
||
if (savedFont->info)
|
||
free(savedFont->info);
|
||
}
|
||
|
||
/*
|
||
* Defines the colors to be used for the forthcoming draw_text calls.
|
||
*
|
||
*/
|
||
void set_font_colors(xcb_gcontext_t gc, uint32_t foreground, uint32_t background) {
|
||
assert(savedFont != NULL);
|
||
uint32_t mask = XCB_GC_FOREGROUND | XCB_GC_BACKGROUND | XCB_GC_FONT;
|
||
uint32_t values[] = { foreground, background, savedFont->id };
|
||
xcb_change_gc(conn, gc, mask, values);
|
||
}
|
||
|
||
/*
|
||
* Draws text onto the specified X drawable (normally a pixmap) at the
|
||
* specified coordinates (from the top left corner of the leftmost, uppermost
|
||
* glyph) and using the provided gc.
|
||
*
|
||
* Text can be specified as UCS-2 or UTF-8. If it's specified as UCS-2, then
|
||
* text_len must be the number of glyphs in the string. If it's specified as
|
||
* UTF-8, then text_len must be the number of bytes in the string (not counting
|
||
* the null terminator).
|
||
*
|
||
*/
|
||
void draw_text(char *text, size_t text_len, bool is_ucs2, xcb_drawable_t drawable,
|
||
xcb_gcontext_t gc, int x, int y, int max_width) {
|
||
assert(savedFont != NULL);
|
||
assert(text_len != 0);
|
||
|
||
/* X11 coordinates for fonts start at the baseline */
|
||
int pos_y = y + savedFont->info->font_ascent;
|
||
|
||
/* As an optimization, check if we can bypass conversion */
|
||
if (!is_ucs2 && text_len <= 255) {
|
||
xcb_image_text_8(conn, text_len, drawable, gc, x, pos_y, text);
|
||
return;
|
||
}
|
||
|
||
/* Convert the text into UCS-2 so we can do basic pointer math */
|
||
char *input = (is_ucs2 ? text : (char*)convert_utf8_to_ucs2(text, &text_len));
|
||
|
||
/* The X11 protocol limits text drawing to 255 chars, so we may need
|
||
* multiple calls */
|
||
int pos_x = x;
|
||
int offset = 0;
|
||
for (;;) {
|
||
/* Calculate the size of this chunk */
|
||
int chunk_size = (text_len > 255 ? 255 : text_len);
|
||
xcb_char2b_t *chunk = (xcb_char2b_t*)input + offset;
|
||
|
||
/* Draw it */
|
||
xcb_image_text_16(conn, chunk_size, drawable, gc, pos_x, pos_y, chunk);
|
||
|
||
/* Advance the offset and length of the text to draw */
|
||
offset += chunk_size;
|
||
text_len -= chunk_size;
|
||
|
||
/* Check if we're done */
|
||
if (text_len == 0)
|
||
break;
|
||
|
||
/* Advance pos_x based on the predicted text width */
|
||
pos_x += predict_text_width((char*)chunk, chunk_size, true);
|
||
}
|
||
|
||
/* If we had to convert, free the converted string */
|
||
if (!is_ucs2)
|
||
free(input);
|
||
}
|
||
|
||
static int xcb_query_text_width(xcb_char2b_t *text, size_t text_len) {
|
||
/* Make the user know we’re using the slow path, but only once. */
|
||
static bool first_invocation = true;
|
||
if (first_invocation) {
|
||
fprintf(stderr, "Using slow code path for text extents\n");
|
||
first_invocation = false;
|
||
}
|
||
|
||
/* Query the text width */
|
||
xcb_generic_error_t *error;
|
||
xcb_query_text_extents_cookie_t cookie = xcb_query_text_extents(conn,
|
||
savedFont->id, text_len, (xcb_char2b_t*)text);
|
||
xcb_query_text_extents_reply_t *reply = xcb_query_text_extents_reply(conn,
|
||
cookie, &error);
|
||
if (reply == NULL) {
|
||
/* We return a safe estimate because a rendering error is better than
|
||
* a crash. Plus, the user will see the error in his log. */
|
||
fprintf(stderr, "Could not get text extents (X error code %d)\n",
|
||
error->error_code);
|
||
return savedFont->info->max_bounds.character_width * text_len;
|
||
}
|
||
|
||
int width = reply->overall_width;
|
||
free(reply);
|
||
return width;
|
||
}
|
||
|
||
/*
|
||
* Predict the text width in pixels for the given text. Text can be specified
|
||
* as UCS-2 or UTF-8.
|
||
*
|
||
*/
|
||
int predict_text_width(char *text, size_t text_len, bool is_ucs2) {
|
||
/* Convert the text into UTF-16 so we can do basic pointer math */
|
||
xcb_char2b_t *input;
|
||
if (is_ucs2)
|
||
input = (xcb_char2b_t*)text;
|
||
else
|
||
input = convert_utf8_to_ucs2(text, &text_len);
|
||
|
||
int width;
|
||
if (savedFont->table == NULL) {
|
||
/* If we don't have a font table, fall back to querying the server */
|
||
width = xcb_query_text_width(input, text_len);
|
||
} else {
|
||
/* Save some pointers for convenience */
|
||
xcb_query_font_reply_t *font_info = savedFont->info;
|
||
xcb_charinfo_t *font_table = savedFont->table;
|
||
|
||
/* Calculate the width using the font table */
|
||
width = 0;
|
||
for (size_t i = 0; i < text_len; i++) {
|
||
xcb_charinfo_t *info;
|
||
int row = input[i].byte1;
|
||
int col = input[i].byte2;
|
||
|
||
if (row < font_info->min_byte1 ||
|
||
row > font_info->max_byte1 ||
|
||
col < font_info->min_char_or_byte2 ||
|
||
col > font_info->max_char_or_byte2)
|
||
continue;
|
||
|
||
/* Don't you ask me, how this one works… (Merovius) */
|
||
info = &font_table[((row - font_info->min_byte1) *
|
||
(font_info->max_char_or_byte2 - font_info->min_char_or_byte2 + 1)) +
|
||
(col - font_info->min_char_or_byte2)];
|
||
|
||
if (info->character_width != 0 ||
|
||
(info->right_side_bearing |
|
||
info->left_side_bearing |
|
||
info->ascent |
|
||
info->descent) != 0) {
|
||
width += info->character_width;
|
||
}
|
||
}
|
||
}
|
||
|
||
/* If we had to convert, free the converted string */
|
||
if (!is_ucs2)
|
||
free(input);
|
||
|
||
return width;
|
||
}
|