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32<td align="right" valign="center"><img src="logo32.png" align="right" width="64" height="32" border="0"></td></tr></table><h1 align=center>QFontMetrics Class Reference</h1>
33
34<p>The QFontMetrics class provides font metrics information.
35<a href="#details">More...</a>
36<p><tt>#include &lt;<a href="qfontmetrics-h.html">qfontmetrics.h</a>&gt;</tt>
37<p><a href="qfontmetrics-members.html">List of all member functions.</a>
38<h2>Public Members</h2>
39<ul>
40<li class=fn><a href="#QFontMetrics"><b>QFontMetrics</b></a> ( const&nbsp;QFont&nbsp;&amp;&nbsp;font )</li>
41<li class=fn><a href="#QFontMetrics-2"><b>QFontMetrics</b></a> ( const&nbsp;QFont&nbsp;&amp;&nbsp;font, QFont::Script&nbsp;script )</li>
42<li class=fn><a href="#QFontMetrics-3"><b>QFontMetrics</b></a> ( const&nbsp;QFontMetrics&nbsp;&amp;&nbsp;fm )</li>
43<li class=fn><a href="#~QFontMetrics"><b>~QFontMetrics</b></a> ()</li>
44<li class=fn>QFontMetrics &amp; <a href="#operator-eq"><b>operator=</b></a> ( const&nbsp;QFontMetrics&nbsp;&amp;&nbsp;fm )</li>
45<li class=fn>int <a href="#ascent"><b>ascent</b></a> () const</li>
46<li class=fn>int <a href="#descent"><b>descent</b></a> () const</li>
47<li class=fn>int <a href="#height"><b>height</b></a> () const</li>
48<li class=fn>int <a href="#leading"><b>leading</b></a> () const</li>
49<li class=fn>int <a href="#lineSpacing"><b>lineSpacing</b></a> () const</li>
50<li class=fn>int <a href="#minLeftBearing"><b>minLeftBearing</b></a> () const</li>
51<li class=fn>int <a href="#minRightBearing"><b>minRightBearing</b></a> () const</li>
52<li class=fn>int <a href="#maxWidth"><b>maxWidth</b></a> () const</li>
53<li class=fn>bool <a href="#inFont"><b>inFont</b></a> ( QChar&nbsp;ch ) const</li>
54<li class=fn>int <a href="#leftBearing"><b>leftBearing</b></a> ( QChar&nbsp;ch ) const</li>
55<li class=fn>int <a href="#rightBearing"><b>rightBearing</b></a> ( QChar&nbsp;ch ) const</li>
56<li class=fn>int <a href="#width-2"><b>width</b></a> ( const&nbsp;QString&nbsp;&amp;&nbsp;str, int&nbsp;len = -1 ) const</li>
57<li class=fn>int <a href="#width"><b>width</b></a> ( QChar&nbsp;ch ) const</li>
58<li class=fn>int width ( char&nbsp;c ) const &nbsp;<em>(obsolete)</em></li>
59<li class=fn>int <a href="#charWidth"><b>charWidth</b></a> ( const&nbsp;QString&nbsp;&amp;&nbsp;str, int&nbsp;pos ) const</li>
60<li class=fn>QRect <a href="#boundingRect-2"><b>boundingRect</b></a> ( const&nbsp;QString&nbsp;&amp;&nbsp;str, int&nbsp;len = -1 ) const</li>
61<li class=fn>QRect <a href="#boundingRect"><b>boundingRect</b></a> ( QChar&nbsp;ch ) const</li>
62<li class=fn>QRect <a href="#boundingRect-3"><b>boundingRect</b></a> ( int&nbsp;x, int&nbsp;y, int&nbsp;w, int&nbsp;h, int&nbsp;flgs, const&nbsp;QString&nbsp;&amp;&nbsp;str, int&nbsp;len = -1, int&nbsp;tabstops = 0, int&nbsp;*&nbsp;tabarray = 0, QTextParag&nbsp;**&nbsp;intern = 0 ) const</li>
63<li class=fn>QSize <a href="#size"><b>size</b></a> ( int&nbsp;flgs, const&nbsp;QString&nbsp;&amp;&nbsp;str, int&nbsp;len = -1, int&nbsp;tabstops = 0, int&nbsp;*&nbsp;tabarray = 0, QTextParag&nbsp;**&nbsp;intern = 0 ) const</li>
64<li class=fn>int <a href="#underlinePos"><b>underlinePos</b></a> () const</li>
65<li class=fn>int <a href="#overlinePos"><b>overlinePos</b></a> () const</li>
66<li class=fn>int <a href="#strikeOutPos"><b>strikeOutPos</b></a> () const</li>
67<li class=fn>int <a href="#lineWidth"><b>lineWidth</b></a> () const</li>
68</ul>
69<hr><a name="details"></a><h2>Detailed Description</h2>
70
71
72The QFontMetrics class provides font metrics information.
73<p>
74
75<p> QFontMetrics functions calculate the size of characters and
76strings for a given font. There are three ways you can create a
77QFontMetrics object:
78<p> <ol type=1>
79<li> Calling the QFontMetrics constructor with a <a href="qfont.html">QFont</a> creates a
80font metrics object for a screen-compatible font, i.e. the font
81cannot be a printer font<sup>*</sup>. If the font is changed
82later, the font metrics object is <em>not</em> updated.
83<p> <li> <a href="qwidget.html#fontMetrics">QWidget::fontMetrics</a>() returns the font metrics for a widget's
84font. This is equivalent to QFontMetrics(widget->font()). If the
85widget's font is changed later, the font metrics object is <em>not</em>
86updated.
87<p> <li> <a href="qpainter.html#fontMetrics">QPainter::fontMetrics</a>() returns the font metrics for a
88painter's current font. If the painter's font is changed later, the
89font metrics object is <em>not</em> updated.
90</ol>
91<p> <sup>*</sup> If you use a printer font the values returned may be
92inaccurate. Printer fonts are not always accessible so the nearest
93screen font is used if a printer font is supplied.
94<p> Once created, the object provides functions to access the
95individual metrics of the font, its characters, and for strings
96rendered in the font.
97<p> There are several functions that operate on the font: <a href="#ascent">ascent</a>(),
98<a href="#descent">descent</a>(), <a href="#height">height</a>(), <a href="#leading">leading</a>() and <a href="#lineSpacing">lineSpacing</a>() return the basic
99size properties of the font. The <a href="#underlinePos">underlinePos</a>(), <a href="#overlinePos">overlinePos</a>(),
100<a href="#strikeOutPos">strikeOutPos</a>() and <a href="#lineWidth">lineWidth</a>() functions, return the properties of
101the line that underlines, overlines or strikes out the
102characters. These functions are all fast.
103<p> There are also some functions that operate on the set of glyphs in
104the font: <a href="#minLeftBearing">minLeftBearing</a>(), <a href="#minRightBearing">minRightBearing</a>() and <a href="#maxWidth">maxWidth</a>().
105These are by necessity slow, and we recommend avoiding them if
106possible.
107<p> For each character, you can get its <a href="#width">width</a>(), <a href="#leftBearing">leftBearing</a>() and
108<a href="#rightBearing">rightBearing</a>() and find out whether it is in the font using
109<a href="#inFont">inFont</a>(). You can also treat the character as a string, and use
110the string functions on it.
111<p> The string functions include width(), to return the width of a
112string in pixels (or points, for a printer), <a href="#boundingRect">boundingRect</a>(), to
113return a rectangle large enough to contain the rendered string,
114and <a href="#size">size</a>(), to return the size of that rectangle.
115<p> Example:
116<pre>
117 <a href="qfont.html">QFont</a> font( "times", 24 );
118 QFontMetrics fm( font );
119 int pixelsWide = fm.<a href="#width">width</a>( "What's the width of this text?" );
120 int pixelsHigh = fm.<a href="#height">height</a>();
121 </pre>
122
123<p> <p>See also <a href="qfont.html">QFont</a>, <a href="qfontinfo.html">QFontInfo</a>, <a href="qfontdatabase.html">QFontDatabase</a>, <a href="graphics.html">Graphics Classes</a>, and <a href="shared.html">Implicitly and Explicitly Shared Classes</a>.
124
125<hr><h2>Member Function Documentation</h2>
126<h3 class=fn><a name="QFontMetrics"></a>QFontMetrics::QFontMetrics ( const&nbsp;<a href="qfont.html">QFont</a>&nbsp;&amp;&nbsp;font )
127</h3>
128Constructs a font metrics object for <em>font</em>.
129<p> The font must be screen-compatible, i.e. a font you use when
130drawing text in <a href="qwidget.html">widgets</a> or <a href="qpixmap.html">pixmaps</a>, not <a href="qpicture.html">QPicture</a> or <a href="qprinter.html">QPrinter</a>.
131<p> The font metrics object holds the information for the font that is
132passed in the constructor at the time it is created, and is not
133updated if the font's attributes are changed later.
134<p> Use <a href="qpainter.html#fontMetrics">QPainter::fontMetrics</a>() to get the font metrics when painting.
135This will give correct results also when painting on paint device
136that is not screen-compatible.
137
138<h3 class=fn><a name="QFontMetrics-2"></a>QFontMetrics::QFontMetrics ( const&nbsp;<a href="qfont.html">QFont</a>&nbsp;&amp;&nbsp;font, <a href="qfont.html#Script-enum">QFont::Script</a>&nbsp;script )
139</h3>
140This is an overloaded member function, provided for convenience. It behaves essentially like the above function.
141<p> Constructs a font metrics object for <em>font</em> using the given <em>script</em>.
142
143<h3 class=fn><a name="QFontMetrics-3"></a>QFontMetrics::QFontMetrics ( const&nbsp;<a href="qfontmetrics.html">QFontMetrics</a>&nbsp;&amp;&nbsp;fm )
144</h3>
145Constructs a copy of <em>fm</em>.
146
147<h3 class=fn><a name="~QFontMetrics"></a>QFontMetrics::~QFontMetrics ()
148</h3>
149Destroys the font metrics object and frees all allocated
150resources.
151
152<h3 class=fn>int <a name="ascent"></a>QFontMetrics::ascent () const
153</h3>
154Returns the ascent of the font.
155<p> The ascent of a font is the distance from the baseline to the
156highest position characters extend to. In practice, some font
157designers break this rule, e.g. when they put more than one accent
158on top of a character, or to accommodate an unusual character in
159an exotic language, so it is possible (though rare) that this
160value will be too small.
161<p> <p>See also <a href="#descent">descent</a>().
162
163<p>Examples: <a href="drawdemo-example.html#x1064">drawdemo/drawdemo.cpp</a> and <a href="scrollview-example.html#x619">scrollview/scrollview.cpp</a>.
164<h3 class=fn><a href="qrect.html">QRect</a> <a name="boundingRect"></a>QFontMetrics::boundingRect ( <a href="qchar.html">QChar</a>&nbsp;ch ) const
165</h3>
166Returns the rectangle that is covered by ink if the character
167specified by <em>ch</em> were to be drawn at the origin of the coordinate
168system.
169<p> Note that the bounding rectangle may extend to the left of (0, 0),
170e.g. for italicized fonts, and that the text output may cover <em>all</em> pixels in the bounding rectangle. For a space character the rectangle
171will usually be empty.
172<p> Note that the rectangle usually extends both above and below the
173base line.
174<p> <b>Warning:</b> The width of the returned rectangle is not the advance width
175of the character. Use <a href="#boundingRect">boundingRect</a>(const <a href="qstring.html">QString</a> &) or <a href="#width">width</a>() instead.
176<p> <p>See also <a href="#width">width</a>().
177
178<p>Example: <a href="xform-example.html#x1225">xform/xform.cpp</a>.
179<h3 class=fn><a href="qrect.html">QRect</a> <a name="boundingRect-2"></a>QFontMetrics::boundingRect ( const&nbsp;<a href="qstring.html">QString</a>&nbsp;&amp;&nbsp;str, int&nbsp;len = -1 ) const
180</h3>
181This is an overloaded member function, provided for convenience. It behaves essentially like the above function.
182<p> Returns the bounding rectangle that contains the first <em>len</em>
183characters of string <em>str</em>.
184
185<h3 class=fn><a href="qrect.html">QRect</a> <a name="boundingRect-3"></a>QFontMetrics::boundingRect ( int&nbsp;x, int&nbsp;y, int&nbsp;w, int&nbsp;h, int&nbsp;flgs, const&nbsp;<a href="qstring.html">QString</a>&nbsp;&amp;&nbsp;str, int&nbsp;len = -1, int&nbsp;tabstops = 0, int&nbsp;*&nbsp;tabarray = 0, QTextParag&nbsp;**&nbsp;intern = 0 ) const
186</h3>
187This is an overloaded member function, provided for convenience. It behaves essentially like the above function.
188<p> Returns the bounding rectangle of the first <em>len</em> characters of
189<em>str</em>, which is the set of pixels the text would cover if drawn
190at (0, 0). The drawing, and hence the bounding rectangle, is
191constrained to the rectangle (<em>x</em>, <em>y</em>, <em>w</em>, <em>h</em>).
192<p> If <em>len</em> is negative (which is the default), the entire string is
193used.
194<p> The <em>flgs</em> argument is the bitwise OR of the following flags:
195<ul>
196<li> <tt>AlignAuto</tt> aligns to the left border for all languages except
197Arabic and Hebrew where it aligns to the right.
198<li> <tt>AlignLeft</tt> aligns to the left border.
199<li> <tt>AlignRight</tt> aligns to the right border.
200<li> <tt>AlignJustify</tt> produces justified text.
201<li> <tt>AlignHCenter</tt> aligns horizontally centered.
202<li> <tt>AlignTop</tt> aligns to the top border.
203<li> <tt>AlignBottom</tt> aligns to the bottom border.
204<li> <tt>AlignVCenter</tt> aligns vertically centered
205<li> <tt>AlignCenter</tt> (== <tt>AlignHCenter | AlignVCenter</tt>)
206<li> <tt>SingleLine</tt> ignores newline characters in the text.
207<li> <tt>ExpandTabs</tt> expands tabs (see below)
208<li> <tt>ShowPrefix</tt> interprets "&amp;x" as "<u>x</u>", i.e. underlined.
209<li> <tt>WordBreak</tt> breaks the text to fit the rectangle.
210</ul>
211<p> Horizontal alignment defaults to <tt>AlignAuto</tt> and vertical
212alignment defaults to <tt>AlignTop</tt>.
213<p> If several of the horizontal or several of the vertical alignment
214flags are set, the resulting alignment is undefined.
215<p> These flags are defined in <a href="qnamespace-h.html">qnamespace.h</a>.
216<p> If <tt>ExpandTabs</tt> is set in <em>flgs</em>, then: if <em>tabarray</em> is
217non-null, it specifies a 0-terminated sequence of pixel-positions
218for tabs; otherwise if <em>tabstops</em> is non-zero, it is used as the
219tab spacing (in pixels).
220<p> Note that the bounding rectangle may extend to the left of (0, 0),
221e.g. for italicized fonts, and that the text output may cover <em>all</em> pixels in the bounding rectangle.
222<p> Newline characters are processed as linebreaks.
223<p> Despite the different actual character heights, the heights of the
224bounding rectangles of "Yes" and "yes" are the same.
225<p> The bounding rectangle given by this function is somewhat larger
226than that calculated by the simpler <a href="#boundingRect">boundingRect</a>() function. This
227function uses the <a href="#minLeftBearing">maximum left</a> and
228<a href="#minRightBearing">right</a> font bearings as is
229necessary for multi-line text to align correctly. Also,
230fontHeight() and <a href="#lineSpacing">lineSpacing</a>() are used to calculate the height,
231rather than individual character heights.
232<p> The <em>intern</em> argument should not be used.
233<p> <p>See also <a href="#width">width</a>(), <a href="qpainter.html#boundingRect">QPainter::boundingRect</a>(), and <a href="qt.html#AlignmentFlags-enum">Qt::AlignmentFlags</a>.
234
235<h3 class=fn>int <a name="charWidth"></a>QFontMetrics::charWidth ( const&nbsp;<a href="qstring.html">QString</a>&nbsp;&amp;&nbsp;str, int&nbsp;pos ) const
236</h3>
237Returns the width of the character at position <em>pos</em> in the
238string <em>str</em>.
239<p> The whole string is needed, as the glyph drawn may change
240depending on the context (the letter before and after the current
241one) for some languages (e.g. Arabic).
242<p> This function also takes non spacing marks and ligatures into
243account.
244
245<h3 class=fn>int <a name="descent"></a>QFontMetrics::descent () const
246</h3>
247Returns the descent of the font.
248<p> The descent is the distance from the base line to the lowest point
249characters extend to. (Note that this is different from X, which
250adds 1 pixel.) In practice, some font designers break this rule,
251e.g. to accommodate an unusual character in an exotic language, so
252it is possible (though rare) that this value will be too small.
253<p> <p>See also <a href="#ascent">ascent</a>().
254
255<p>Examples: <a href="drawdemo-example.html#x1065">drawdemo/drawdemo.cpp</a> and <a href="hello-example.html#x1629">hello/hello.cpp</a>.
256<h3 class=fn>int <a name="height"></a>QFontMetrics::height () const
257</h3>
258Returns the height of the font.
259<p> This is always equal to <a href="#ascent">ascent</a>()+descent()+1 (the 1 is for the
260base line).
261<p> <p>See also <a href="#leading">leading</a>() and <a href="#lineSpacing">lineSpacing</a>().
262
263<p>Examples: <a href="grapher-nsplugin-example.html#x2741">grapher/grapher.cpp</a>, <a href="hello-example.html#x1630">hello/hello.cpp</a>, and <a href="qfd-example.html#x1986">qfd/fontdisplayer.cpp</a>.
264<h3 class=fn>bool <a name="inFont"></a>QFontMetrics::inFont ( <a href="qchar.html">QChar</a>&nbsp;ch ) const
265</h3>
266Returns TRUE if character <em>ch</em> is a valid character in the font;
267otherwise returns FALSE.
268
269<p>Example: <a href="qfd-example.html#x1987">qfd/fontdisplayer.cpp</a>.
270<h3 class=fn>int <a name="leading"></a>QFontMetrics::leading () const
271</h3>
272Returns the leading of the font.
273<p> This is the natural inter-line spacing.
274<p> <p>See also <a href="#height">height</a>() and <a href="#lineSpacing">lineSpacing</a>().
275
276<h3 class=fn>int <a name="leftBearing"></a>QFontMetrics::leftBearing ( <a href="qchar.html">QChar</a>&nbsp;ch ) const
277</h3>
278Returns the left bearing of character <em>ch</em> in the font.
279<p> The left bearing is the right-ward distance of the left-most pixel
280of the character from the logical origin of the character. This
281value is negative if the pixels of the character extend to the
282left of the logical origin.
283<p> See <a href="#width">width</a>(<a href="qchar.html">QChar</a>) for a graphical description of this metric.
284<p> <p>See also <a href="#rightBearing">rightBearing</a>(), <a href="#minLeftBearing">minLeftBearing</a>(), and <a href="#width">width</a>().
285
286<p>Example: <a href="qfd-example.html#x1988">qfd/fontdisplayer.cpp</a>.
287<h3 class=fn>int <a name="lineSpacing"></a>QFontMetrics::lineSpacing () const
288</h3>
289Returns the distance from one base line to the next.
290<p> This value is always equal to <a href="#leading">leading</a>()+height().
291<p> <p>See also <a href="#height">height</a>() and <a href="#leading">leading</a>().
292
293<p>Examples: <a href="qfd-example.html#x1989">qfd/fontdisplayer.cpp</a>, <a href="qwerty-example.html#x369">qwerty/qwerty.cpp</a>, and <a href="scrollview-example.html#x620">scrollview/scrollview.cpp</a>.
294<h3 class=fn>int <a name="lineWidth"></a>QFontMetrics::lineWidth () const
295</h3>
296Returns the width of the underline and strikeout lines, adjusted
297for the point size of the font.
298<p> <p>See also <a href="#underlinePos">underlinePos</a>(), <a href="#overlinePos">overlinePos</a>(), and <a href="#strikeOutPos">strikeOutPos</a>().
299
300<h3 class=fn>int <a name="maxWidth"></a>QFontMetrics::maxWidth () const
301</h3>
302Returns the width of the widest character in the font.
303
304<p>Example: <a href="qfd-example.html#x1990">qfd/fontdisplayer.cpp</a>.
305<h3 class=fn>int <a name="minLeftBearing"></a>QFontMetrics::minLeftBearing () const
306</h3>
307Returns the minimum left bearing of the font.
308<p> This is the smallest <a href="#leftBearing">leftBearing</a>(char) of all characters in the
309font.
310<p> Note that this function can be very slow if the font is large.
311<p> <p>See also <a href="#minRightBearing">minRightBearing</a>() and <a href="#leftBearing">leftBearing</a>().
312
313<p>Example: <a href="qfd-example.html#x1991">qfd/fontdisplayer.cpp</a>.
314<h3 class=fn>int <a name="minRightBearing"></a>QFontMetrics::minRightBearing () const
315</h3>
316Returns the minimum right bearing of the font.
317<p> This is the smallest <a href="#rightBearing">rightBearing</a>(char) of all characters in the
318font.
319<p> Note that this function can be very slow if the font is large.
320<p> <p>See also <a href="#minLeftBearing">minLeftBearing</a>() and <a href="#rightBearing">rightBearing</a>().
321
322<p>Example: <a href="qfd-example.html#x1992">qfd/fontdisplayer.cpp</a>.
323<h3 class=fn><a href="qfontmetrics.html">QFontMetrics</a>&nbsp;&amp; <a name="operator-eq"></a>QFontMetrics::operator= ( const&nbsp;<a href="qfontmetrics.html">QFontMetrics</a>&nbsp;&amp;&nbsp;fm )
324</h3>
325Assigns the font metrics <em>fm</em>.
326
327<h3 class=fn>int <a name="overlinePos"></a>QFontMetrics::overlinePos () const
328</h3>
329Returns the distance from the base line to where an overline
330should be drawn.
331<p> <p>See also <a href="#underlinePos">underlinePos</a>(), <a href="#strikeOutPos">strikeOutPos</a>(), and <a href="#lineWidth">lineWidth</a>().
332
333<h3 class=fn>int <a name="rightBearing"></a>QFontMetrics::rightBearing ( <a href="qchar.html">QChar</a>&nbsp;ch ) const
334</h3>
335Returns the right bearing of character <em>ch</em> in the font.
336<p> The right bearing is the left-ward distance of the right-most
337pixel of the character from the logical origin of a subsequent
338character. This value is negative if the pixels of the character
339extend to the right of the <a href="#width">width</a>() of the character.
340<p> See width() for a graphical description of this metric.
341<p> <p>See also <a href="#leftBearing">leftBearing</a>(), <a href="#minRightBearing">minRightBearing</a>(), and <a href="#width">width</a>().
342
343<p>Example: <a href="qfd-example.html#x1993">qfd/fontdisplayer.cpp</a>.
344<h3 class=fn><a href="qsize.html">QSize</a> <a name="size"></a>QFontMetrics::size ( int&nbsp;flgs, const&nbsp;<a href="qstring.html">QString</a>&nbsp;&amp;&nbsp;str, int&nbsp;len = -1, int&nbsp;tabstops = 0, int&nbsp;*&nbsp;tabarray = 0, QTextParag&nbsp;**&nbsp;intern = 0 ) const
345</h3>
346Returns the size in pixels of the first <em>len</em> characters of <em>str</em>.
347<p> If <em>len</em> is negative (the default), the entire string is used.
348<p> The <em>flgs</em> argument is the bitwise OR of the following flags:
349<ul>
350<li> <tt>SingleLine</tt> ignores newline characters.
351<li> <tt>ExpandTabs</tt> expands tabs (see below)
352<li> <tt>ShowPrefix</tt> interprets "&amp;x" as "<u>x</u>", i.e. underlined.
353<li> <tt>WordBreak</tt> breaks the text to fit the rectangle.
354</ul>
355<p> These flags are defined in <a href="qnamespace-h.html">qnamespace.h</a>.
356<p> If <tt>ExpandTabs</tt> is set in <em>flgs</em>, then: if <em>tabarray</em> is
357non-null, it specifies a 0-terminated sequence of pixel-positions
358for tabs; otherwise if <em>tabstops</em> is non-zero, it is used as the
359tab spacing (in pixels).
360<p> Newline characters are processed as linebreaks.
361<p> Despite the different actual character heights, the heights of the
362bounding rectangles of "Yes" and "yes" are the same.
363<p> The <em>intern</em> argument should not be used.
364<p> <p>See also <a href="#boundingRect">boundingRect</a>().
365
366<h3 class=fn>int <a name="strikeOutPos"></a>QFontMetrics::strikeOutPos () const
367</h3>
368Returns the distance from the base line to where the strikeout
369line should be drawn.
370<p> <p>See also <a href="#underlinePos">underlinePos</a>(), <a href="#overlinePos">overlinePos</a>(), and <a href="#lineWidth">lineWidth</a>().
371
372<h3 class=fn>int <a name="underlinePos"></a>QFontMetrics::underlinePos () const
373</h3>
374Returns the distance from the base line to where an underscore
375should be drawn.
376<p> <p>See also <a href="#overlinePos">overlinePos</a>(), <a href="#strikeOutPos">strikeOutPos</a>(), and <a href="#lineWidth">lineWidth</a>().
377
378<h3 class=fn>int <a name="width"></a>QFontMetrics::width ( <a href="qchar.html">QChar</a>&nbsp;ch ) const
379</h3>
380<p> <img src="bearings.png" align=right>
381<p> Returns the logical width of character <em>ch</em> in pixels. This is a
382distance appropriate for drawing a subsequent character after <em>ch</em>.
383<p> Some of the metrics are described in the image to the right. The
384central dark rectangles cover the logical <a href="#width">width</a>() of each
385character. The outer pale rectangles cover the <a href="#leftBearing">leftBearing</a>() and
386<a href="#rightBearing">rightBearing</a>() of each character. Notice that the bearings of "f"
387in this particular font are both negative, while the bearings of
388"o" are both positive.
389<p> <b>Warning:</b> This function will produce incorrect results for Arabic
390characters or non spacing marks in the middle of a string, as the
391glyph shaping and positioning of marks that happens when
392processing strings cannot be taken into account. Use <a href="#charWidth">charWidth</a>()
393instead if you aren't looking for the width of isolated
394characters.
395<p> <p>See also <a href="#boundingRect">boundingRect</a>() and <a href="#charWidth">charWidth</a>().
396
397<p>Examples: <a href="drawdemo-example.html#x1066">drawdemo/drawdemo.cpp</a>, <a href="hello-example.html#x1631">hello/hello.cpp</a>, <a href="movies-example.html#x496">movies/main.cpp</a>, <a href="qfd-example.html#x1994">qfd/fontdisplayer.cpp</a>, and <a href="scrollview-example.html#x621">scrollview/scrollview.cpp</a>.
398<h3 class=fn>int <a name="width-2"></a>QFontMetrics::width ( const&nbsp;<a href="qstring.html">QString</a>&nbsp;&amp;&nbsp;str, int&nbsp;len = -1 ) const
399</h3>
400This is an overloaded member function, provided for convenience. It behaves essentially like the above function.
401<p> Returns the width of the first <em>len</em> characters of string <em>str</em>.
402
403<h3 class=fn>int <a name="width-3"></a>QFontMetrics::width ( char&nbsp;c ) const
404</h3>
405<p> This is an overloaded member function, provided for convenience. It behaves essentially like the above function.
406<p> <b>This function is obsolete.</b> It is provided to keep old source working. We strongly advise against using it in new code.
407<p> Provided to aid porting from Qt 1.x.
408
409<!-- eof -->
410<hr><p>
411This file is part of the <a href="index.html">Qt toolkit</a>.
412Copyright &copy; 1995-2007
413<a href="http://www.trolltech.com/">Trolltech</a>. All Rights Reserved.<p><address><hr><div align=center>
414<table width=100% cellspacing=0 border=0><tr>
415<td>Copyright &copy; 2007
416<a href="troll.html">Trolltech</a><td align=center><a href="trademarks.html">Trademarks</a>
417<td align=right><div align=right>Qt 3.3.8</div>
418</table></div></address></body>
419</html>
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