1xcb_query_text_extents(3)        XCB Requests        xcb_query_text_extents(3)
2
3
4

NAME

6       xcb_query_text_extents - get text extents
7

SYNOPSIS

9       #include <xcb/xproto.h>
10
11   Request function
12       xcb_query_text_extents_cookie_t
13              xcb_query_text_extents(xcb_connection_t *conn,
14              xcb_fontable_t font, uint32_t string_len, const
15              xcb_char2b_t *string);
16
17   Reply datastructure
18       typedef struct xcb_query_text_extents_reply_t {
19           uint8_t  response_type;
20           uint8_t  draw_direction;
21           uint16_t sequence;
22           uint32_t length;
23           int16_t  font_ascent;
24           int16_t  font_descent;
25           int16_t  overall_ascent;
26           int16_t  overall_descent;
27           int32_t  overall_width;
28           int32_t  overall_left;
29           int32_t  overall_right;
30       } xcb_query_text_extents_reply_t;
31
32   Reply function
33       xcb_query_text_extents_reply_t
34              *xcb_query_text_extents_reply(xcb_connection_t *conn,
35              xcb_query_text_extents_cookie_t cookie,
36              xcb_generic_error_t **e);
37

REQUEST ARGUMENTS

39       conn      The XCB connection to X11.
40
41       font      The font to calculate text extents in. You can also pass a
42                 graphics context.
43
44       string_len
45                 The number of characters in string.
46
47       string    The text to get text extents for.
48

REPLY FIELDS

50       response_type
51                 The type of this reply, in this case XCB_QUERY_TEXT_EXTENTS.
52                 This field is also present in the xcb_generic_reply_t and can
53                 be used to tell replies apart from each other.
54
55       sequence  The sequence number of the last request processed by the X11
56                 server.
57
58       length    The length of the reply, in words (a word is 4 bytes).
59
60       draw_direction
61                 One of the following values:
62
63                 XCB_FONT_DRAW_LEFT_TO_RIGHT
64                           TODO: NOT YET DOCUMENTED.
65
66                 XCB_FONT_DRAW_RIGHT_TO_LEFT
67                           TODO: NOT YET DOCUMENTED.
68                 TODO: NOT YET DOCUMENTED.
69
70       font_ascent
71                 TODO: NOT YET DOCUMENTED.
72
73       font_descent
74                 TODO: NOT YET DOCUMENTED.
75
76       overall_ascent
77                 TODO: NOT YET DOCUMENTED.
78
79       overall_descent
80                 TODO: NOT YET DOCUMENTED.
81
82       overall_width
83                 TODO: NOT YET DOCUMENTED.
84
85       overall_left
86                 TODO: NOT YET DOCUMENTED.
87
88       overall_right
89                 TODO: NOT YET DOCUMENTED.
90

DESCRIPTION

92       Query text extents from the X11 server. This request returns the bound‐
93       ing box of the specified 16-bit character string in the specified font
94       or the font contained in the specified graphics context.
95
96       font_ascent is set to the maximum of the ascent metrics of all charac‐
97       ters in the string. font_descent is set to the maximum of the descent
98       metrics.  overall_width is set to the sum of the character-width met‐
99       rics of all characters in the string. For each character in the string,
100       let W be the sum of the character-width metrics of all characters pre‐
101       ceding it in the string. Let L be the left-side-bearing metric of the
102       character plus W. Let R be the right-side-bearing metric of the charac‐
103       ter plus W. The lbearing member is set to the minimum L of all charac‐
104       ters in the string. The rbearing member is set to the maximum R.
105
106       For fonts defined with linear indexing rather than 2-byte matrix index‐
107       ing, each xcb_char2b_t structure is interpreted as a 16-bit number with
108       byte1 as the most significant byte. If the font has no defined default
109       character, undefined characters in the string are taken to have all ze‐
110       ro metrics.
111
112       Characters with all zero metrics are ignored. If the font has no de‐
113       fined default_char, the undefined characters in the string are also ig‐
114       nored.
115

RETURN VALUE

117       Returns an xcb_query_text_extents_cookie_t. Errors have to be handled
118       when calling the reply function xcb_query_text_extents_reply.
119
120       If you want to handle errors in the event loop instead, use
121       xcb_query_text_extents_unchecked. See xcb-requests(3) for details.
122

ERRORS

124       xcb_font_error_t
125                 The specified font does not exist.
126
127       xcb_g_context_error_t
128                 The specified graphics context does not exist.
129

SEE ALSO

131       xcb-requests(3)
132

AUTHOR

134       Generated from xproto.xml. Contact xcb@lists.freedesktop.org for cor‐
135       rections and improvements.
136
137
138
139X Version 11                      libxcb 1.13        xcb_query_text_extents(3)
Impressum