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<td >Qt 5.12</td><td ><a href="qtopengl-index.html">Qt OpenGL</a></td><td ><a href="qtopengl-module.html">C++ Classes</a></td><td >QGLBuffer</td></tr></table><table class="buildversion"><tr>
<td id="buildversion" width="100%" align="right"><a href="qtopengl-index.html">Qt 5.12.6 Reference Documentation</a></td>
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<h3><a name="toc">Contents</a></h3>
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<li class="level1"><a href="#public-types">Public Types</a></li>
<li class="level1"><a href="#public-functions">Public Functions</a></li>
<li class="level1"><a href="#static-public-members">Static Public Members</a></li>
<li class="level1"><a href="#details">Detailed Description</a></li>
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<h1 class="title">QGLBuffer Class</h1>
<!-- $$$QGLBuffer-brief -->
<p>The <a href="qglbuffer.html">QGLBuffer</a> class provides functions for creating and managing GL buffer objects. <a href="#details">More...</a></p>
<!-- @@@QGLBuffer -->
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<tr><td class="memItemLeft rightAlign topAlign"> Header:</td><td class="memItemRight bottomAlign"> <span class="preprocessor">#include <QGLBuffer></span>
</td></tr><tr><td class="memItemLeft rightAlign topAlign"> qmake:</td><td class="memItemRight bottomAlign"> QT += opengl</td></tr><tr><td class="memItemLeft rightAlign topAlign"> Since:</td><td class="memItemRight bottomAlign"> Qt 4.7</td></tr></table></div><p><b>This class is obsolete.</b> It is provided to keep old source code working. We strongly advise against using it in new code.</p>
<ul>
<li><a href="qglbuffer-members.html">List of all members, including inherited members</a></li>
</ul>
<a name="public-types"></a>
<h2 id="public-types">Public Types</h2>
<div class="table"><table class="alignedsummary">
<tr><td class="memItemLeft rightAlign topAlign"> enum </td><td class="memItemRight bottomAlign"><b><a href="qglbuffer.html#Access-enum">Access</a></b> { ReadOnly, WriteOnly, ReadWrite }</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> enum </td><td class="memItemRight bottomAlign"><b><a href="qglbuffer.html#Type-enum">Type</a></b> { VertexBuffer, IndexBuffer, PixelPackBuffer, PixelUnpackBuffer }</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> enum </td><td class="memItemRight bottomAlign"><b><a href="qglbuffer.html#UsagePattern-enum">UsagePattern</a></b> { StreamDraw, StreamRead, StreamCopy, StaticDraw, ..., DynamicCopy }</td></tr>
</table></div>
<a name="public-functions"></a>
<h2 id="public-functions">Public Functions</h2>
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<tr><td class="memItemLeft rightAlign topAlign"> </td><td class="memItemRight bottomAlign"><b><a href="qglbuffer.html#QGLBuffer">QGLBuffer</a></b>()</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> </td><td class="memItemRight bottomAlign"><b><a href="qglbuffer.html#QGLBuffer-1">QGLBuffer</a></b>(QGLBuffer::Type <i>type</i>)</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> </td><td class="memItemRight bottomAlign"><b><a href="qglbuffer.html#QGLBuffer-2">QGLBuffer</a></b>(const QGLBuffer &<i>other</i>)</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> </td><td class="memItemRight bottomAlign"><b><a href="qglbuffer.html#dtor.QGLBuffer">~QGLBuffer</a></b>()</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> void </td><td class="memItemRight bottomAlign"><b><a href="qglbuffer.html#allocate">allocate</a></b>(const void *<i>data</i>, int <i>count</i>)</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> void </td><td class="memItemRight bottomAlign"><b><a href="qglbuffer.html#allocate-1">allocate</a></b>(int <i>count</i>)</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> bool </td><td class="memItemRight bottomAlign"><b><a href="qglbuffer.html#bind">bind</a></b>()</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> GLuint </td><td class="memItemRight bottomAlign"><b><a href="qglbuffer.html#bufferId">bufferId</a></b>() const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> bool </td><td class="memItemRight bottomAlign"><b><a href="qglbuffer.html#create">create</a></b>()</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> void </td><td class="memItemRight bottomAlign"><b><a href="qglbuffer.html#destroy">destroy</a></b>()</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> bool </td><td class="memItemRight bottomAlign"><b><a href="qglbuffer.html#isCreated">isCreated</a></b>() const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> void *</td><td class="memItemRight bottomAlign"><b><a href="qglbuffer.html#map">map</a></b>(QGLBuffer::Access <i>access</i>)</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> bool </td><td class="memItemRight bottomAlign"><b><a href="qglbuffer.html#read">read</a></b>(int <i>offset</i>, void *<i>data</i>, int <i>count</i>)</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> void </td><td class="memItemRight bottomAlign"><b><a href="qglbuffer.html#release">release</a></b>()</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> void </td><td class="memItemRight bottomAlign"><b><a href="qglbuffer.html#setUsagePattern">setUsagePattern</a></b>(QGLBuffer::UsagePattern <i>value</i>)</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> int </td><td class="memItemRight bottomAlign"><b><a href="qglbuffer.html#size">size</a></b>() const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> QGLBuffer::Type </td><td class="memItemRight bottomAlign"><b><a href="qglbuffer.html#type">type</a></b>() const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> bool </td><td class="memItemRight bottomAlign"><b><a href="qglbuffer.html#unmap">unmap</a></b>()</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> QGLBuffer::UsagePattern </td><td class="memItemRight bottomAlign"><b><a href="qglbuffer.html#usagePattern">usagePattern</a></b>() const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> void </td><td class="memItemRight bottomAlign"><b><a href="qglbuffer.html#write">write</a></b>(int <i>offset</i>, const void *<i>data</i>, int <i>count</i>)</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> QGLBuffer &</td><td class="memItemRight bottomAlign"><b><a href="qglbuffer.html#operator-eq">operator=</a></b>(const QGLBuffer &<i>other</i>)</td></tr>
</table></div>
<a name="static-public-members"></a>
<h2 id="static-public-members">Static Public Members</h2>
<div class="table"><table class="alignedsummary">
<tr><td class="memItemLeft rightAlign topAlign"> void </td><td class="memItemRight bottomAlign"><b><a href="qglbuffer.html#release-1">release</a></b>(QGLBuffer::Type <i>type</i>)</td></tr>
</table></div>
<a name="details"></a>
<!-- $$$QGLBuffer-description -->
<div class="descr">
<h2 id="details">Detailed Description</h2>
<p>The <a href="qglbuffer.html">QGLBuffer</a> class provides functions for creating and managing GL buffer objects.</p>
<p>Buffer objects are created in the GL server so that the client application can avoid uploading vertices, indices, texture image data, etc every time they are needed.</p>
<p><a href="qglbuffer.html">QGLBuffer</a> objects can be copied around as a reference to the underlying GL buffer object:</p>
<pre class="cpp">
<span class="type"><a href="qglbuffer.html#QGLBuffer">QGLBuffer</a></span> buffer1(<span class="type"><a href="qglbuffer.html#QGLBuffer">QGLBuffer</a></span><span class="operator">::</span>IndexBuffer);
buffer1<span class="operator">.</span>create();
<span class="type"><a href="qglbuffer.html#QGLBuffer">QGLBuffer</a></span> buffer2 <span class="operator">=</span> buffer1;
</pre>
<p><a href="qglbuffer.html">QGLBuffer</a> performs a shallow copy when objects are copied in this manner, but does not implement copy-on-write semantics. The original object will be affected whenever the copy is modified.</p>
<p><b>Note: </b>This class has been deprecated in favor of <a href="../qtgui/qopenglbuffer.html">QOpenGLBuffer</a>.</p></div>
<!-- @@@QGLBuffer -->
<div class="types">
<h2>Member Type Documentation</h2>
<!-- $$$Access$$$ReadOnly$$$WriteOnly$$$ReadWrite -->
<h3 class="fn" id="Access-enum"><a name="Access-enum"></a>enum QGLBuffer::<span class="name">Access</span></h3>
<p>This enum defines the access mode for <a href="qglbuffer.html#map">QGLBuffer::map</a>().</p>
<div class="table"><table class="valuelist"><tr valign="top" class="odd"><th class="tblConst">Constant</th><th class="tblval">Value</th><th class="tbldscr">Description</th></tr>
<tr><td class="topAlign"><code>QGLBuffer::ReadOnly</code></td><td class="topAlign tblval"><code>0x88B8</code></td><td class="topAlign">The buffer will be mapped for reading only.</td></tr>
<tr><td class="topAlign"><code>QGLBuffer::WriteOnly</code></td><td class="topAlign tblval"><code>0x88B9</code></td><td class="topAlign">The buffer will be mapped for writing only.</td></tr>
<tr><td class="topAlign"><code>QGLBuffer::ReadWrite</code></td><td class="topAlign tblval"><code>0x88BA</code></td><td class="topAlign">The buffer will be mapped for reading and writing.</td></tr>
</table></div>
<!-- @@@Access -->
<!-- $$$Type$$$VertexBuffer$$$IndexBuffer$$$PixelPackBuffer$$$PixelUnpackBuffer -->
<h3 class="fn" id="Type-enum"><a name="Type-enum"></a>enum QGLBuffer::<span class="name">Type</span></h3>
<p>This enum defines the type of GL buffer object to create with <a href="qglbuffer.html" class="obsolete">QGLBuffer</a>.</p>
<div class="table"><table class="valuelist"><tr valign="top" class="odd"><th class="tblConst">Constant</th><th class="tblval">Value</th><th class="tbldscr">Description</th></tr>
<tr><td class="topAlign"><code>QGLBuffer::VertexBuffer</code></td><td class="topAlign tblval"><code>0x8892</code></td><td class="topAlign">Vertex buffer object for use when specifying vertex arrays.</td></tr>
<tr><td class="topAlign"><code>QGLBuffer::IndexBuffer</code></td><td class="topAlign tblval"><code>0x8893</code></td><td class="topAlign">Index buffer object for use with <code>glDrawElements()</code>.</td></tr>
<tr><td class="topAlign"><code>QGLBuffer::PixelPackBuffer</code></td><td class="topAlign tblval"><code>0x88EB</code></td><td class="topAlign">Pixel pack buffer object for reading pixel data from the GL server (for example, with <code>glReadPixels()</code>). Not supported under OpenGL/ES.</td></tr>
<tr><td class="topAlign"><code>QGLBuffer::PixelUnpackBuffer</code></td><td class="topAlign tblval"><code>0x88EC</code></td><td class="topAlign">Pixel unpack buffer object for writing pixel data to the GL server (for example, with <code>glTexImage2D()</code>). Not supported under OpenGL/ES.</td></tr>
</table></div>
<!-- @@@Type -->
<!-- $$$UsagePattern$$$StreamDraw$$$StreamRead$$$StreamCopy$$$StaticDraw$$$StaticRead$$$StaticCopy$$$DynamicDraw$$$DynamicRead$$$DynamicCopy -->
<h3 class="fn" id="UsagePattern-enum"><a name="UsagePattern-enum"></a>enum QGLBuffer::<span class="name">UsagePattern</span></h3>
<p>This enum defines the usage pattern of a <a href="qglbuffer.html" class="obsolete">QGLBuffer</a> object.</p>
<div class="table"><table class="valuelist"><tr valign="top" class="odd"><th class="tblConst">Constant</th><th class="tblval">Value</th><th class="tbldscr">Description</th></tr>
<tr><td class="topAlign"><code>QGLBuffer::StreamDraw</code></td><td class="topAlign tblval"><code>0x88E0</code></td><td class="topAlign">The data will be set once and used a few times for drawing operations. Under OpenGL/ES 1.1 this is identical to StaticDraw.</td></tr>
<tr><td class="topAlign"><code>QGLBuffer::StreamRead</code></td><td class="topAlign tblval"><code>0x88E1</code></td><td class="topAlign">The data will be set once and used a few times for reading data back from the GL server. Not supported under OpenGL/ES.</td></tr>
<tr><td class="topAlign"><code>QGLBuffer::StreamCopy</code></td><td class="topAlign tblval"><code>0x88E2</code></td><td class="topAlign">The data will be set once and used a few times for reading data back from the GL server for use in further drawing operations. Not supported under OpenGL/ES.</td></tr>
<tr><td class="topAlign"><code>QGLBuffer::StaticDraw</code></td><td class="topAlign tblval"><code>0x88E4</code></td><td class="topAlign">The data will be set once and used many times for drawing operations.</td></tr>
<tr><td class="topAlign"><code>QGLBuffer::StaticRead</code></td><td class="topAlign tblval"><code>0x88E5</code></td><td class="topAlign">The data will be set once and used many times for reading data back from the GL server. Not supported under OpenGL/ES.</td></tr>
<tr><td class="topAlign"><code>QGLBuffer::StaticCopy</code></td><td class="topAlign tblval"><code>0x88E6</code></td><td class="topAlign">The data will be set once and used many times for reading data back from the GL server for use in further drawing operations. Not supported under OpenGL/ES.</td></tr>
<tr><td class="topAlign"><code>QGLBuffer::DynamicDraw</code></td><td class="topAlign tblval"><code>0x88E8</code></td><td class="topAlign">The data will be modified repeatedly and used many times for drawing operations.</td></tr>
<tr><td class="topAlign"><code>QGLBuffer::DynamicRead</code></td><td class="topAlign tblval"><code>0x88E9</code></td><td class="topAlign">The data will be modified repeatedly and used many times for reading data back from the GL server. Not supported under OpenGL/ES.</td></tr>
<tr><td class="topAlign"><code>QGLBuffer::DynamicCopy</code></td><td class="topAlign tblval"><code>0x88EA</code></td><td class="topAlign">The data will be modified repeatedly and used many times for reading data back from the GL server for use in further drawing operations. Not supported under OpenGL/ES.</td></tr>
</table></div>
<!-- @@@UsagePattern -->
</div>
<div class="func">
<h2>Member Function Documentation</h2>
<!-- $$$QGLBuffer[overload1]$$$QGLBuffer -->
<h3 class="fn" id="QGLBuffer"><a name="QGLBuffer"></a>QGLBuffer::<span class="name">QGLBuffer</span>()</h3>
<p>Constructs a new buffer object of type <a href="qglbuffer.html#Type-enum">QGLBuffer::VertexBuffer</a>.</p>
<p>Note: this constructor just creates the <a href="qglbuffer.html" class="obsolete">QGLBuffer</a> instance. The actual buffer object in the GL server is not created until <a href="qglbuffer.html#create">create</a>() is called.</p>
<p><b>See also </b><a href="qglbuffer.html#create">create</a>().</p>
<!-- @@@QGLBuffer -->
<!-- $$$QGLBuffer$$$QGLBufferQGLBuffer::Type -->
<h3 class="fn" id="QGLBuffer-1"><a name="QGLBuffer-1"></a>QGLBuffer::<span class="name">QGLBuffer</span>(<span class="type"><a href="qglbuffer.html#Type-enum">QGLBuffer::Type</a></span> <i>type</i>)</h3>
<p>Constructs a new buffer object of <i>type</i>.</p>
<p>Note: this constructor just creates the <a href="qglbuffer.html" class="obsolete">QGLBuffer</a> instance. The actual buffer object in the GL server is not created until <a href="qglbuffer.html#create">create</a>() is called.</p>
<p><b>See also </b><a href="qglbuffer.html#create">create</a>().</p>
<!-- @@@QGLBuffer -->
<!-- $$$QGLBuffer$$$QGLBufferconstQGLBuffer& -->
<h3 class="fn" id="QGLBuffer-2"><a name="QGLBuffer-2"></a>QGLBuffer::<span class="name">QGLBuffer</span>(const <span class="type"><a href="qglbuffer.html#QGLBuffer">QGLBuffer</a></span> &<i>other</i>)</h3>
<p>Constructs a shallow copy of <i>other</i>.</p>
<p>Note: <a href="qglbuffer.html" class="obsolete">QGLBuffer</a> does not implement copy-on-write semantics, so <i>other</i> will be affected whenever the copy is modified.</p>
<!-- @@@QGLBuffer -->
<!-- $$$~QGLBuffer[overload1]$$$~QGLBuffer -->
<h3 class="fn" id="dtor.QGLBuffer"><a name="dtor.QGLBuffer"></a>QGLBuffer::<span class="name">~QGLBuffer</span>()</h3>
<p>Destroys this buffer object, including the storage being used in the GL server.</p>
<!-- @@@~QGLBuffer -->
<!-- $$$allocate[overload1]$$$allocateconstvoid*int -->
<h3 class="fn" id="allocate"><a name="allocate"></a><span class="type">void</span> QGLBuffer::<span class="name">allocate</span>(const <span class="type">void</span> *<i>data</i>, <span class="type">int</span> <i>count</i>)</h3>
<p>Allocates <i>count</i> bytes of space to the buffer, initialized to the contents of <i>data</i>. Any previous contents will be removed.</p>
<p>It is assumed that <a href="qglbuffer.html#create">create</a>() has been called on this buffer and that it has been bound to the current context.</p>
<p><b>See also </b><a href="qglbuffer.html#create">create</a>(), <a href="qglbuffer.html#read">read</a>(), and <a href="qglbuffer.html#write">write</a>().</p>
<!-- @@@allocate -->
<!-- $$$allocate$$$allocateint -->
<h3 class="fn" id="allocate-1"><a name="allocate-1"></a><span class="type">void</span> QGLBuffer::<span class="name">allocate</span>(<span class="type">int</span> <i>count</i>)</h3>
<p>This is an overloaded function.</p>
<p>Allocates <i>count</i> bytes of space to the buffer. Any previous contents will be removed.</p>
<p>It is assumed that <a href="qglbuffer.html#create">create</a>() has been called on this buffer and that it has been bound to the current context.</p>
<p><b>See also </b><a href="qglbuffer.html#create">create</a>() and <a href="qglbuffer.html#write">write</a>().</p>
<!-- @@@allocate -->
<!-- $$$bind[overload1]$$$bind -->
<h3 class="fn" id="bind"><a name="bind"></a><span class="type">bool</span> QGLBuffer::<span class="name">bind</span>()</h3>
<p>Binds the buffer associated with this object to the current GL context. Returns <code>false</code> if binding was not possible, usually because <a href="qglbuffer.html#type">type</a>() is not supported on this GL implementation.</p>
<p>The buffer must be bound to the same QGLContext current when <a href="qglbuffer.html#create">create</a>() was called, or to another QGLContext that is sharing with it. Otherwise, false will be returned from this function.</p>
<p><b>See also </b><a href="qglbuffer.html#release">release</a>() and <a href="qglbuffer.html#create">create</a>().</p>
<!-- @@@bind -->
<!-- $$$bufferId[overload1]$$$bufferId -->
<h3 class="fn" id="bufferId"><a name="bufferId"></a><span class="type">GLuint</span> QGLBuffer::<span class="name">bufferId</span>() const</h3>
<p>Returns the GL identifier associated with this buffer; zero if the buffer has not been created.</p>
<p><b>See also </b><a href="qglbuffer.html#isCreated">isCreated</a>().</p>
<!-- @@@bufferId -->
<!-- $$$create[overload1]$$$create -->
<h3 class="fn" id="create"><a name="create"></a><span class="type">bool</span> QGLBuffer::<span class="name">create</span>()</h3>
<p>Creates the buffer object in the GL server. Returns <code>true</code> if the object was created; false otherwise.</p>
<p>This function must be called with a current QGLContext. The buffer will be bound to and can only be used in that context (or any other context that is shared with it).</p>
<p>This function will return false if the GL implementation does not support buffers, or there is no current QGLContext.</p>
<p><b>See also </b><a href="qglbuffer.html#isCreated">isCreated</a>(), <a href="qglbuffer.html#allocate">allocate</a>(), <a href="qglbuffer.html#write">write</a>(), and <a href="qglbuffer.html#destroy">destroy</a>().</p>
<!-- @@@create -->
<!-- $$$destroy[overload1]$$$destroy -->
<h3 class="fn" id="destroy"><a name="destroy"></a><span class="type">void</span> QGLBuffer::<span class="name">destroy</span>()</h3>
<p>Destroys this buffer object, including the storage being used in the GL server. All references to the buffer will become invalid.</p>
<!-- @@@destroy -->
<!-- $$$isCreated[overload1]$$$isCreated -->
<h3 class="fn" id="isCreated"><a name="isCreated"></a><span class="type">bool</span> QGLBuffer::<span class="name">isCreated</span>() const</h3>
<p>Returns <code>true</code> if this buffer has been created; false otherwise.</p>
<p><b>See also </b><a href="qglbuffer.html#create">create</a>() and <a href="qglbuffer.html#destroy">destroy</a>().</p>
<!-- @@@isCreated -->
<!-- $$$map[overload1]$$$mapQGLBuffer::Access -->
<h3 class="fn" id="map"><a name="map"></a><span class="type">void</span> *QGLBuffer::<span class="name">map</span>(<span class="type"><a href="qglbuffer.html#Access-enum">QGLBuffer::Access</a></span> <i>access</i>)</h3>
<p>Maps the contents of this buffer into the application's memory space and returns a pointer to it. Returns null if memory mapping is not possible. The <i>access</i> parameter indicates the type of access to be performed.</p>
<p>It is assumed that <a href="qglbuffer.html#create">create</a>() has been called on this buffer and that it has been bound to the current context.</p>
<p>This function is only supported under OpenGL/ES if the <code>GL_OES_mapbuffer</code> extension is present.</p>
<p><b>See also </b><a href="qglbuffer.html#unmap">unmap</a>(), <a href="qglbuffer.html#create">create</a>(), and <a href="qglbuffer.html#bind">bind</a>().</p>
<!-- @@@map -->
<!-- $$$read[overload1]$$$readintvoid*int -->
<h3 class="fn" id="read"><a name="read"></a><span class="type">bool</span> QGLBuffer::<span class="name">read</span>(<span class="type">int</span> <i>offset</i>, <span class="type">void</span> *<i>data</i>, <span class="type">int</span> <i>count</i>)</h3>
<p>Reads the <i>count</i> bytes in this buffer starting at <i>offset</i> into <i>data</i>. Returns <code>true</code> on success; false if reading from the buffer is not supported. Buffer reading is not supported under OpenGL/ES.</p>
<p>It is assumed that this buffer has been bound to the current context.</p>
<p><b>See also </b><a href="qglbuffer.html#write">write</a>() and <a href="qglbuffer.html#bind">bind</a>().</p>
<!-- @@@read -->
<!-- $$$release[overload1]$$$release -->
<h3 class="fn" id="release"><a name="release"></a><span class="type">void</span> QGLBuffer::<span class="name">release</span>()</h3>
<p>Releases the buffer associated with this object from the current GL context.</p>
<p>This function must be called with the same QGLContext current as when <a href="qglbuffer.html#bind">bind</a>() was called on the buffer.</p>
<p><b>See also </b><a href="qglbuffer.html#bind">bind</a>().</p>
<!-- @@@release -->
<!-- $$$release$$$releaseQGLBuffer::Type -->
<h3 class="fn" id="release-1"><a name="release-1"></a><code>[static] </code><span class="type">void</span> QGLBuffer::<span class="name">release</span>(<span class="type"><a href="qglbuffer.html#Type-enum">QGLBuffer::Type</a></span> <i>type</i>)</h3>
<p>Releases the buffer associated with <i>type</i> in the current QGLContext.</p>
<p>This function is a direct call to <code>glBindBuffer(type, 0)</code> for use when the caller does not know which <a href="qglbuffer.html" class="obsolete">QGLBuffer</a> has been bound to the context but wants to make sure that it is released.</p>
<pre class="cpp">
<span class="type"><a href="qglbuffer.html#QGLBuffer">QGLBuffer</a></span><span class="operator">::</span>release(<span class="type"><a href="qglbuffer.html#QGLBuffer">QGLBuffer</a></span><span class="operator">::</span>VertexBuffer);
</pre>
<!-- @@@release -->
<!-- $$$setUsagePattern[overload1]$$$setUsagePatternQGLBuffer::UsagePattern -->
<h3 class="fn" id="setUsagePattern"><a name="setUsagePattern"></a><span class="type">void</span> QGLBuffer::<span class="name">setUsagePattern</span>(<span class="type"><a href="qglbuffer.html#UsagePattern-enum">QGLBuffer::UsagePattern</a></span> <i>value</i>)</h3>
<p>Sets the usage pattern for this buffer object to <i>value</i>. This function must be called before <a href="qglbuffer.html#allocate">allocate</a>() or <a href="qglbuffer.html#write">write</a>().</p>
<p><b>See also </b><a href="qglbuffer.html#usagePattern">usagePattern</a>(), <a href="qglbuffer.html#allocate">allocate</a>(), and <a href="qglbuffer.html#write">write</a>().</p>
<!-- @@@setUsagePattern -->
<!-- $$$size[overload1]$$$size -->
<h3 class="fn" id="size"><a name="size"></a><span class="type">int</span> QGLBuffer::<span class="name">size</span>() const</h3>
<p>Returns the size of the data in this buffer, for reading operations. Returns -1 if fetching the buffer size is not supported, or the buffer has not been created.</p>
<p>It is assumed that this buffer has been bound to the current context.</p>
<p><b>See also </b><a href="qglbuffer.html#isCreated">isCreated</a>() and <a href="qglbuffer.html#bind">bind</a>().</p>
<!-- @@@size -->
<!-- $$$type[overload1]$$$type -->
<h3 class="fn" id="type"><a name="type"></a><span class="type"><a href="qglbuffer.html#Type-enum">QGLBuffer::Type</a></span> QGLBuffer::<span class="name">type</span>() const</h3>
<p>Returns the type of buffer represented by this object.</p>
<!-- @@@type -->
<!-- $$$unmap[overload1]$$$unmap -->
<h3 class="fn" id="unmap"><a name="unmap"></a><span class="type">bool</span> QGLBuffer::<span class="name">unmap</span>()</h3>
<p>Unmaps the buffer after it was mapped into the application's memory space with a previous call to <a href="qglbuffer.html#map">map</a>(). Returns <code>true</code> if the unmap succeeded; false otherwise.</p>
<p>It is assumed that this buffer has been bound to the current context, and that it was previously mapped with <a href="qglbuffer.html#map">map</a>().</p>
<p>This function is only supported under OpenGL/ES if the <code>GL_OES_mapbuffer</code> extension is present.</p>
<p><b>See also </b><a href="qglbuffer.html#map">map</a>().</p>
<!-- @@@unmap -->
<!-- $$$usagePattern[overload1]$$$usagePattern -->
<h3 class="fn" id="usagePattern"><a name="usagePattern"></a><span class="type"><a href="qglbuffer.html#UsagePattern-enum">QGLBuffer::UsagePattern</a></span> QGLBuffer::<span class="name">usagePattern</span>() const</h3>
<p>Returns the usage pattern for this buffer object. The default value is <a href="qglbuffer.html#UsagePattern-enum">StaticDraw</a>.</p>
<p><b>See also </b><a href="qglbuffer.html#setUsagePattern">setUsagePattern</a>().</p>
<!-- @@@usagePattern -->
<!-- $$$write[overload1]$$$writeintconstvoid*int -->
<h3 class="fn" id="write"><a name="write"></a><span class="type">void</span> QGLBuffer::<span class="name">write</span>(<span class="type">int</span> <i>offset</i>, const <span class="type">void</span> *<i>data</i>, <span class="type">int</span> <i>count</i>)</h3>
<p>Replaces the <i>count</i> bytes of this buffer starting at <i>offset</i> with the contents of <i>data</i>. Any other bytes in the buffer will be left unmodified.</p>
<p>It is assumed that <a href="qglbuffer.html#create">create</a>() has been called on this buffer and that it has been bound to the current context.</p>
<p><b>See also </b><a href="qglbuffer.html#create">create</a>(), <a href="qglbuffer.html#read">read</a>(), and <a href="qglbuffer.html#allocate">allocate</a>().</p>
<!-- @@@write -->
<!-- $$$operator=[overload1]$$$operator=constQGLBuffer& -->
<h3 class="fn" id="operator-eq"><a name="operator-eq"></a><span class="type"><a href="qglbuffer.html#QGLBuffer">QGLBuffer</a></span> &QGLBuffer::<span class="name">operator=</span>(const <span class="type"><a href="qglbuffer.html#QGLBuffer">QGLBuffer</a></span> &<i>other</i>)</h3>
<p>Assigns a shallow copy of <i>other</i> to this object.</p>
<p>Note: <a href="qglbuffer.html" class="obsolete">QGLBuffer</a> does not implement copy-on-write semantics, so <i>other</i> will be affected whenever the copy is modified.</p>
<!-- @@@operator= -->
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distrib
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Mageia
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armv7hl
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core-updates
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d5e62c01ae8d1e579463c6a871dd44bf
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