gdk-visuals.html

最新gtk中文资料集

<tr>
<td><p><span class="term"><a
href="/usr/share/gtk-doc/html/glib/glib-Basic-Types.html#gint"
>gint</a>&#160;<em class="structfield"><code>green_shift</code></em>;</span></p></td>
<td>The <em class="structfield"><code>green_shift</code></em> and
    <em class="structfield"><code>green_prec</code></em> give an alternate presentation
    of the information in <em class="structfield"><code>green_mask</code></em>.
</td>
</tr>
<tr>
<td><p><span class="term"><a
href="/usr/share/gtk-doc/html/glib/glib-Basic-Types.html#gint"
>gint</a>&#160;<em class="structfield"><code>green_prec</code></em>;</span></p></td>
<td>See above.
</td>
</tr>
<tr>
<td><p><span class="term"><a
href="/usr/share/gtk-doc/html/glib/glib-Basic-Types.html#guint32"
>guint32</a>&#160;<em class="structfield"><code>blue_mask</code></em>;</span></p></td>
<td>A mask giving the bits in a pixel value that
    correspond to the blue field.
</td>
</tr>
<tr>
<td><p><span class="term"><a
href="/usr/share/gtk-doc/html/glib/glib-Basic-Types.html#gint"
>gint</a>&#160;<em class="structfield"><code>blue_shift</code></em>;</span></p></td>
<td>The <em class="structfield"><code>blue_shift</code></em> and
    <em class="structfield"><code>blue_prec</code></em> give an alternate presentation
    of the information in <em class="structfield"><code>blue_mask</code></em>.
</td>
</tr>
<tr>
<td><p><span class="term"><a
href="/usr/share/gtk-doc/html/glib/glib-Basic-Types.html#gint"
>gint</a>&#160;<em class="structfield"><code>blue_prec</code></em>;</span></p></td>
<td>See above.

</td>
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</table></div>
</div>
<hr>
<div class="refsect2" lang="en">
<a name="id3155320"></a><h3>
<a name="GdkVisualType"></a>enum GdkVisualType</h3>
<a class="indexterm" name="id3155332"></a><pre class="programlisting">typedef enum
{
  GDK_VISUAL_STATIC_GRAY,
  GDK_VISUAL_GRAYSCALE,
  GDK_VISUAL_STATIC_COLOR,
  GDK_VISUAL_PSEUDO_COLOR,
  GDK_VISUAL_TRUE_COLOR,
  GDK_VISUAL_DIRECT_COLOR
} GdkVisualType;
</pre>
<p>
A set of values that describe the manner in which the
pixel values for a visual are converted into RGB
values for display.
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td><p><span class="term"><a name="GDK-VISUAL-STATIC-GRAY:CAPS"></a><code class="literal">GDK_VISUAL_STATIC_GRAY</code></span></p></td>
<td>Each pixel value indexes a grayscale value directly.
</td>
</tr>
<tr>
<td><p><span class="term"><a name="GDK-VISUAL-GRAYSCALE:CAPS"></a><code class="literal">GDK_VISUAL_GRAYSCALE</code></span></p></td>
<td>Each pixel is an index into a color map that maps pixel 
   values into grayscale values. The color map can be changed by an application.
</td>
</tr>
<tr>
<td><p><span class="term"><a name="GDK-VISUAL-STATIC-COLOR:CAPS"></a><code class="literal">GDK_VISUAL_STATIC_COLOR</code></span></p></td>
<td>Each pixel value is an index into a predefined,
   unmodifiable color map that maps pixel values into RGB values.
</td>
</tr>
<tr>
<td><p><span class="term"><a name="GDK-VISUAL-PSEUDO-COLOR:CAPS"></a><code class="literal">GDK_VISUAL_PSEUDO_COLOR</code></span></p></td>
<td>Each pixel is an index into a color map that maps
   pixel values into rgb values. The color map can be changed by an application.
</td>
</tr>
<tr>
<td><p><span class="term"><a name="GDK-VISUAL-TRUE-COLOR:CAPS"></a><code class="literal">GDK_VISUAL_TRUE_COLOR</code></span></p></td>
<td>Each pixel value directly contains red, green,
   and blue components. The <em class="structfield"><code>red_mask</code></em>,
   <em class="structfield"><code>green_mask</code></em>, and 
   <em class="structfield"><code>blue_mask</code></em> fields of the <a class="link" href="gdk-Visuals.html#GdkVisual"><span class="type">GdkVisual</span></a>
   structure describe how the components are assembled into a pixel value.
</td>
</tr>
<tr>
<td><p><span class="term"><a name="GDK-VISUAL-DIRECT-COLOR:CAPS"></a><code class="literal">GDK_VISUAL_DIRECT_COLOR</code></span></p></td>
<td>Each pixel value contains red, green, and blue
   components as for <a class="link" href="gdk-Visuals.html#GDK-VISUAL-TRUE-COLOR:CAPS"><code class="literal">GDK_VISUAL_TRUE_COLOR</code></a>, but the components are mapped via a 
   color table into the final output table instead of being converted directly.

</td>
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</tbody>
</table></div>
</div>
<hr>
<div class="refsect2" lang="en">
<a name="id3155533"></a><h3>
<a name="GdkByteOrder"></a>enum GdkByteOrder</h3>
<a class="indexterm" name="id3155546"></a><pre class="programlisting">typedef enum
{
  GDK_LSB_FIRST,
  GDK_MSB_FIRST
} GdkByteOrder;
</pre>
<p>
A set of values describing the possible byte-orders
for storing pixel values in memory.
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td><p><span class="term"><a name="GDK-LSB-FIRST:CAPS"></a><code class="literal">GDK_LSB_FIRST</code></span></p></td>
<td>The values are stored with the least-significant byte
  first. For instance, the 32-bit value 0xffeecc would be stored
  in memory as 0xcc, 0xee, 0xff, 0x00.
</td>
</tr>
<tr>
<td><p><span class="term"><a name="GDK-MSB-FIRST:CAPS"></a><code class="literal">GDK_MSB_FIRST</code></span></p></td>
<td>The values are stored with the most-significant byte
first. For instance, the 32-bit value 0xffeecc would be stored
in memory as 0x00, 0xcc, 0xee, 0xff.

</td>
</tr>
</tbody>
</table></div>
</div>
<hr>
<div class="refsect2" lang="en">
<a name="id3155617"></a><h3>
<a name="gdk-query-depths"></a>gdk_query_depths ()</h3>
<a class="indexterm" name="id3155630"></a><pre class="programlisting">void                gdk_query_depths                    (<a
href="/usr/share/gtk-doc/html/glib/glib-Basic-Types.html#gint"
>gint</a> **depths,
                                                         <a
href="/usr/share/gtk-doc/html/glib/glib-Basic-Types.html#gint"
>gint</a> *count);</pre>
<p>
This function returns the available bit depths for the default
screen. It's equivalent to listing the visuals
(<a class="link" href="gdk-Visuals.html#gdk-list-visuals"><code class="function">gdk_list_visuals()</code></a>) and then looking at the depth field in each
visual, removing duplicates.
</p>
<p>
The array returned by this function should not be freed.</p>
<p>

</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td><p><span class="term"><em class="parameter"><code>depths</code></em>&#160;:</span></p></td>
<td> return location for available depths 
</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>count</code></em>&#160;:</span></p></td>
<td> return location for number of available depths
</td>
</tr>
</tbody>
</table></div>
</div>
<hr>
<div class="refsect2" lang="en">
<a name="id3155720"></a><h3>
<a name="gdk-query-visual-types"></a>gdk_query_visual_types ()</h3>
<a class="indexterm" name="id3155733"></a><pre class="programlisting">void                gdk_query_visual_types              (<a class="link" href="gdk-Visuals.html#GdkVisualType">GdkVisualType</a> **visual_types,
                                                         <a
href="/usr/share/gtk-doc/html/glib/glib-Basic-Types.html#gint"
>gint</a> *count);</pre>
<p>
This function returns the available visual types for the default
screen. It's equivalent to listing the visuals
(<a class="link" href="gdk-Visuals.html#gdk-list-visuals"><code class="function">gdk_list_visuals()</code></a>) and then looking at the type field in each
visual, removing duplicates.
</p>
<p>
The array returned by this function should not be freed.</p>
<p>

</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td><p><span class="term"><em class="parameter"><code>visual_types</code></em>&#160;:</span></p></td>
<td> return location for the available visual types
</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>count</code></em>&#160;:</span></p></td>
<td> return location for the number of available visual types
</td>
</tr>
</tbody>
</table></div>
</div>
<hr>
<div class="refsect2" lang="en">
<a name="id3155825"></a><h3>
<a name="gdk-list-visuals"></a>gdk_list_visuals ()</h3>
<a class="indexterm" name="id3155838"></a><pre class="programlisting"><a
href="/usr/share/gtk-doc/html/glib/glib-Doubly-Linked-Lists.html#GList"
>GList</a>*              gdk_list_visuals                    (void);</pre>
<p>
Lists the available visuals for the default screen.
(See <a class="link" href="GdkScreen.html#gdk-screen-list-visuals"><code class="function">gdk_screen_list_visuals()</code></a>)
A visual describes a hardware image data format.
For example, a visual might support 24-bit color, or 8-bit color,
and might expect pixels to be in a certain format.
</p>
<p>
Call <a
href="/usr/share/gtk-doc/html/glib/glib-Doubly-Linked-Lists.html#g-list-free"
><code class="function">g_list_free()</code></a> on the return value when you're finished with it.</p>
<p>

</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody><tr>
<td><p><span class="term"><span class="emphasis"><em>Returns</em></span>&#160;:</span></p></td>
<td> a list of visuals; the list must be freed, but not its contents
</td>
</tr></tbody>
</table></div>
</div>
<hr>
<div class="refsect2" lang="en">
<a name="id3155907"></a><h3>
<a name="gdk-visual-get-best-depth"></a>gdk_visual_get_best_depth ()</h3>
<a class="indexterm" name="id3155921"></a><pre class="programlisting"><a
href="/usr/share/gtk-doc/html/glib/glib-Basic-Types.html#gint"
>gint</a>                gdk_visual_get_best_depth           (void);</pre>
<p>
Get the best available depth for the default GDK screen.  "Best"
means "largest," i.e. 32 preferred over 24 preferred over 8 bits
per pixel.</p>
<p>

</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody><tr>
<td><p><span class="term"><span class="emphasis"><em>Returns</em></span>&#160;:</span></p></td>
<td> best available depth
</td>
</tr></tbody>