<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/xhtml;charset=UTF-8"/>
<meta http-equiv="X-UA-Compatible" content="IE=9"/>
<meta name="generator" content="Doxygen 1.8.11"/>
<title>GLFW: Window guide</title>
<link href="tabs.css" rel="stylesheet" type="text/css"/>
<script type="text/javascript" src="jquery.js"></script>
<script type="text/javascript" src="dynsections.js"></script>
<link href="search/search.css" rel="stylesheet" type="text/css"/>
<script type="text/javascript" src="search/searchdata.js"></script>
<script type="text/javascript" src="search/search.js"></script>
<script type="text/javascript">
  $(document).ready(function() { init_search(); });
</script>
<link href="doxygen.css" rel="stylesheet" type="text/css" />
<link href="extra.css" rel="stylesheet" type="text/css"/>
</head>
<body>
<div id="top"><!-- do not remove this div, it is closed by doxygen! -->
<div id="titlearea">
	<div class="glfwheader">
		<a href="http://www.glfw.org/" id="glfwhome">GLFW</a>
		<ul class="glfwnavbar">
			<li><a href="http://www.glfw.org/documentation.html">Documentation</a></li>
			<li><a href="http://www.glfw.org/download.html">Download</a></li>
			<li><a href="http://www.glfw.org/media.html">Media</a></li>
			<li><a href="http://www.glfw.org/community.html">Community</a></li>
		</ul>
	</div>
</div>
<!-- end header part -->
<!-- Generated by Doxygen 1.8.11 -->
<script type="text/javascript">
var searchBox = new SearchBox("searchBox", "search",false,'Search');
</script>
  <div id="navrow1" class="tabs">
    <ul class="tablist">
      <li><a href="index.html"><span>Main&#160;Page</span></a></li>
      <li class="current"><a href="pages.html"><span>Related&#160;Pages</span></a></li>
      <li><a href="modules.html"><span>Modules</span></a></li>
      <li><a href="annotated.html"><span>Data&#160;Structures</span></a></li>
      <li><a href="files.html"><span>Files</span></a></li>
      <li>
        <div id="MSearchBox" class="MSearchBoxInactive">
        <span class="left">
          <img id="MSearchSelect" src="search/mag_sel.png"
               onmouseover="return searchBox.OnSearchSelectShow()"
               onmouseout="return searchBox.OnSearchSelectHide()"
               alt=""/>
          <input type="text" id="MSearchField" value="Search" accesskey="S"
               onfocus="searchBox.OnSearchFieldFocus(true)" 
               onblur="searchBox.OnSearchFieldFocus(false)" 
               onkeyup="searchBox.OnSearchFieldChange(event)"/>
          </span><span class="right">
            <a id="MSearchClose" href="javascript:searchBox.CloseResultsWindow()"><img id="MSearchCloseImg" border="0" src="search/close.png" alt=""/></a>
          </span>
        </div>
      </li>
    </ul>
  </div>
<!-- window showing the filter options -->
<div id="MSearchSelectWindow"
     onmouseover="return searchBox.OnSearchSelectShow()"
     onmouseout="return searchBox.OnSearchSelectHide()"
     onkeydown="return searchBox.OnSearchSelectKey(event)">
</div>

<!-- iframe showing the search results (closed by default) -->
<div id="MSearchResultsWindow">
<iframe src="javascript:void(0)" frameborder="0" 
        name="MSearchResults" id="MSearchResults">
</iframe>
</div>

</div><!-- top -->
<div class="header">
  <div class="headertitle">
<div class="title">Window guide </div>  </div>
</div><!--header-->
<div class="contents">
<div class="toc"><h3>Table of Contents</h3>
<ul><li class="level1"><a href="#window_object">Window objects</a><ul><li class="level2"><a href="#window_creation">Window creation</a><ul><li class="level3"><a href="#window_full_screen">Full screen windows</a></li>
<li class="level3"><a href="#window_windowed_full_screen">&quot;Windowed full screen&quot; windows</a></li>
</ul>
</li>
<li class="level2"><a href="#window_destruction">Window destruction</a></li>
<li class="level2"><a href="#window_hints">Window creation hints</a><ul><li class="level3"><a href="#window_hints_hard">Hard and soft constraints</a></li>
<li class="level3"><a href="#window_hints_wnd">Window related hints</a></li>
<li class="level3"><a href="#window_hints_fb">Framebuffer related hints</a></li>
<li class="level3"><a href="#window_hints_mtr">Monitor related hints</a></li>
<li class="level3"><a href="#window_hints_ctx">Context related hints</a></li>
<li class="level3"><a href="#window_hints_values">Supported and default values</a></li>
</ul>
</li>
</ul>
</li>
<li class="level1"><a href="#window_events">Window event processing</a></li>
<li class="level1"><a href="#window_properties">Window properties and events</a><ul><li class="level2"><a href="#window_userptr">User pointer</a></li>
<li class="level2"><a href="#window_close">Window closing and close flag</a></li>
<li class="level2"><a href="#window_size">Window size</a></li>
<li class="level2"><a href="#window_fbsize">Framebuffer size</a></li>
<li class="level2"><a href="#window_sizelimits">Window size limits</a></li>
<li class="level2"><a href="#window_pos">Window position</a></li>
<li class="level2"><a href="#window_title">Window title</a></li>
<li class="level2"><a href="#window_icon">Window icon</a></li>
<li class="level2"><a href="#window_monitor">Window monitor</a></li>
<li class="level2"><a href="#window_iconify">Window iconification</a></li>
<li class="level2"><a href="#window_hide">Window visibility</a></li>
<li class="level2"><a href="#window_focus">Window input focus</a></li>
<li class="level2"><a href="#window_refresh">Window damage and refresh</a></li>
<li class="level2"><a href="#window_attribs">Window attributes</a><ul><li class="level3"><a href="#window_attribs_wnd">Window related attributes</a></li>
<li class="level3"><a href="#window_attribs_ctx">Context related attributes</a></li>
<li class="level3"><a href="#window_attribs_fb">Framebuffer related attributes</a></li>
</ul>
</li>
</ul>
</li>
<li class="level1"><a href="#buffer_swap">Buffer swapping</a></li>
</ul>
</div>
<div class="textblock"><p>This guide introduces the window related functions of GLFW. For details on a specific function in this category, see the <a class="el" href="group__window.html">Window reference</a>. There are also guides for the other areas of GLFW.</p>
<ul>
<li><a class="el" href="intro_guide.html">Introduction to the API</a></li>
<li><a class="el" href="context_guide.html">Context guide</a></li>
<li><a class="el" href="vulkan_guide.html">Vulkan guide</a></li>
<li><a class="el" href="monitor_guide.html">Monitor guide</a></li>
<li><a class="el" href="input_guide.html">Input guide</a></li>
</ul>
<h1><a class="anchor" id="window_object"></a>
Window objects</h1>
<p>The <a class="el" href="group__window.html#ga3c96d80d363e67d13a41b5d1821f3242">GLFWwindow</a> object encapsulates both a window and a context. They are created with <a class="el" href="group__window.html#ga5c336fddf2cbb5b92f65f10fb6043344">glfwCreateWindow</a> and destroyed with <a class="el" href="group__window.html#gacdf43e51376051d2c091662e9fe3d7b2">glfwDestroyWindow</a>, or <a class="el" href="group__init.html#gaaae48c0a18607ea4a4ba951d939f0901">glfwTerminate</a>, if any remain. As the window and context are inseparably linked, the object pointer is used as both a context and window handle.</p>
<p>To see the event stream provided to the various window related callbacks, run the <code>events</code> test program.</p>
<h2><a class="anchor" id="window_creation"></a>
Window creation</h2>
<p>A window and its OpenGL or OpenGL ES context are created with <a class="el" href="group__window.html#ga5c336fddf2cbb5b92f65f10fb6043344">glfwCreateWindow</a>, which returns a handle to the created window object. For example, this creates a 640 by 480 windowed mode window:</p>
<div class="fragment"><div class="line"><a class="code" href="group__window.html#ga3c96d80d363e67d13a41b5d1821f3242">GLFWwindow</a>* window = <a class="code" href="group__window.html#ga5c336fddf2cbb5b92f65f10fb6043344">glfwCreateWindow</a>(640, 480, <span class="stringliteral">&quot;My Title&quot;</span>, NULL, NULL);</div></div><!-- fragment --><p>If window creation fails, <code>NULL</code> will be returned, so it is necessary to check the return value.</p>
<p>The window handle is passed to all window related functions and is provided to along with all input events, so event handlers can tell which window received the event.</p>
<h3><a class="anchor" id="window_full_screen"></a>
Full screen windows</h3>
<p>To create a full screen window, you need to specify which monitor the window should use. In most cases, the user's primary monitor is a good choice. For more information about retrieving monitors, see <a class="el" href="monitor_guide.html#monitor_monitors">Retrieving monitors</a>.</p>
<div class="fragment"><div class="line"><a class="code" href="group__window.html#ga3c96d80d363e67d13a41b5d1821f3242">GLFWwindow</a>* window = <a class="code" href="group__window.html#ga5c336fddf2cbb5b92f65f10fb6043344">glfwCreateWindow</a>(640, 480, <span class="stringliteral">&quot;My Title&quot;</span>, <a class="code" href="group__monitor.html#ga721867d84c6d18d6790d64d2847ca0b1">glfwGetPrimaryMonitor</a>(), NULL);</div></div><!-- fragment --><p>Full screen windows cover the entire display area of a monitor, have no border or decorations.</p>
<p>Windowed mode windows can be made full screen by setting a monitor with <a class="el" href="group__window.html#ga81c76c418af80a1cce7055bccb0ae0a7">glfwSetWindowMonitor</a>, and full screen ones can be made windowed by unsetting it with the same function.</p>
<p>Each field of the <a class="el" href="structGLFWvidmode.html">GLFWvidmode</a> structure corresponds to a function parameter or window hint and combine to form the <em>desired video mode</em> for that window. The supported video mode most closely matching the desired video mode will be set for the chosen monitor as long as the window has input focus. For more information about retrieving video modes, see <a class="el" href="monitor_guide.html#monitor_modes">Video modes</a>.</p>
<table class="doxtable">
<tr>
<th>Video mode field </th><th>Corresponds to  </th></tr>
<tr>
<td><a class="el" href="structGLFWvidmode.html#a698dcb200562051a7249cb6ae154c71d">GLFWvidmode.width</a> </td><td><code>width</code> parameter </td></tr>
<tr>
<td><a class="el" href="structGLFWvidmode.html#ac65942a5f6981695517437a9d571d03c">GLFWvidmode.height</a> </td><td><code>height</code> parameter </td></tr>
<tr>
<td><a class="el" href="structGLFWvidmode.html#a6066c4ecd251098700062d3b735dba1b">GLFWvidmode.redBits</a> </td><td><code>GLFW_RED_BITS</code> hint </td></tr>
<tr>
<td><a class="el" href="structGLFWvidmode.html#a292fdd281f3485fb3ff102a5bda43faa">GLFWvidmode.greenBits</a> </td><td><code>GLFW_GREEN_BITS</code> hint </td></tr>
<tr>
<td><a class="el" href="structGLFWvidmode.html#af310977f58d2e3b188175b6e3d314047">GLFWvidmode.blueBits</a> </td><td><code>GLFW_BLUE_BITS</code> hint </td></tr>
<tr>
<td><a class="el" href="structGLFWvidmode.html#a791bdd6c7697b09f7e9c97054bf05649">GLFWvidmode.refreshRate</a> </td><td><code>GLFW_REFRESH_RATE</code> hint </td></tr>
</table>
<p>Once you have a full screen window, you can change its resolution, refresh rate and monitor with <a class="el" href="group__window.html#ga81c76c418af80a1cce7055bccb0ae0a7">glfwSetWindowMonitor</a>. If you just need change its resolution you can also call <a class="el" href="group__window.html#ga371911f12c74c504dd8d47d832d095cb">glfwSetWindowSize</a>. In all cases, the new video mode will be selected the same way as the video mode chosen by <a class="el" href="group__window.html#ga5c336fddf2cbb5b92f65f10fb6043344">glfwCreateWindow</a>. If the window has an OpenGL or OpenGL ES context, it will be unaffected.</p>
<p>By default, the original video mode of the monitor will be restored and the window iconified if it loses input focus, to allow the user to switch back to the desktop. This behavior can be disabled with the <code>GLFW_AUTO_ICONIFY</code> window hint, for example if you wish to simultaneously cover multiple windows with full screen windows.</p>
<h3><a class="anchor" id="window_windowed_full_screen"></a>
"Windowed full screen" windows</h3>
<p>If the closest match for the desired video mode is the current one, the video mode will not be changed, making window creation faster and application switching much smoother. This is sometimes called <em>windowed full screen</em> or <em>borderless full screen</em> window and counts as a full screen window. To create such a window, simply request the current video mode.</p>
<div class="fragment"><div class="line"><span class="keyword">const</span> <a class="code" href="structGLFWvidmode.html">GLFWvidmode</a>* mode = <a class="code" href="group__monitor.html#gafc1bb972a921ad5b3bd5d63a95fc2d52">glfwGetVideoMode</a>(monitor);</div><div class="line"></div><div class="line"><a class="code" href="group__window.html#ga7d9c8c62384b1e2821c4dc48952d2033">glfwWindowHint</a>(<a class="code" href="glfw3_8h.html#af78ed8e417dbcc1e354906cc2708c982">GLFW_RED_BITS</a>, mode-&gt;<a class="code" href="structGLFWvidmode.html#a6066c4ecd251098700062d3b735dba1b">redBits</a>);</div><div class="line"><a class="code" href="group__window.html#ga7d9c8c62384b1e2821c4dc48952d2033">glfwWindowHint</a>(<a class="code" href="glfw3_8h.html#afba3b72638c914e5fb8a237dd4c50d4d">GLFW_GREEN_BITS</a>, mode-&gt;<a class="code" href="structGLFWvidmode.html#a292fdd281f3485fb3ff102a5bda43faa">greenBits</a>);</div><div class="line"><a class="code" href="group__window.html#ga7d9c8c62384b1e2821c4dc48952d2033">glfwWindowHint</a>(<a class="code" href="glfw3_8h.html#ab292ea403db6d514537b515311bf9ae3">GLFW_BLUE_BITS</a>, mode-&gt;<a class="code" href="structGLFWvidmode.html#af310977f58d2e3b188175b6e3d314047">blueBits</a>);</div><div class="line"><a class="code" href="group__window.html#ga7d9c8c62384b1e2821c4dc48952d2033">glfwWindowHint</a>(<a class="code" href="glfw3_8h.html#a0f20825e6e47ee8ba389024519682212">GLFW_REFRESH_RATE</a>, mode-&gt;<a class="code" href="structGLFWvidmode.html#a791bdd6c7697b09f7e9c97054bf05649">refreshRate</a>);</div><div class="line"></div><div class="line"><a class="code" href="group__window.html#ga3c96d80d363e67d13a41b5d1821f3242">GLFWwindow</a>* window = <a class="code" href="group__window.html#ga5c336fddf2cbb5b92f65f10fb6043344">glfwCreateWindow</a>(mode-&gt;<a class="code" href="structGLFWvidmode.html#a698dcb200562051a7249cb6ae154c71d">width</a>, mode-&gt;<a class="code" href="structGLFWvidmode.html#ac65942a5f6981695517437a9d571d03c">height</a>, <span class="stringliteral">&quot;My Title&quot;</span>, monitor, NULL);</div></div><!-- fragment --><p>This also works for windowed mode windows that are made full screen.</p>
<div class="fragment"><div class="line"><span class="keyword">const</span> <a class="code" href="structGLFWvidmode.html">GLFWvidmode</a>* mode = <a class="code" href="group__monitor.html#gafc1bb972a921ad5b3bd5d63a95fc2d52">glfwGetVideoMode</a>(monitor);</div><div class="line"></div><div class="line"><a class="code" href="group__window.html#ga81c76c418af80a1cce7055bccb0ae0a7">glfwSetWindowMonitor</a>(window, monitor, 0, 0, mode-&gt;<a class="code" href="structGLFWvidmode.html#a698dcb200562051a7249cb6ae154c71d">width</a>, mode-&gt;<a class="code" href="structGLFWvidmode.html#ac65942a5f6981695517437a9d571d03c">height</a>, mode-&gt;<a class="code" href="structGLFWvidmode.html#a791bdd6c7697b09f7e9c97054bf05649">refreshRate</a>);</div></div><!-- fragment --><p>Note that <a class="el" href="group__monitor.html#gafc1bb972a921ad5b3bd5d63a95fc2d52">glfwGetVideoMode</a> returns the <em>current</em> video mode of a monitor, so if you already have a full screen window on that monitor that you want to make windowed full screen, you need to have saved the desktop resolution before.</p>
<h2><a class="anchor" id="window_destruction"></a>
Window destruction</h2>
<p>When a window is no longer needed, destroy it with <a class="el" href="group__window.html#gacdf43e51376051d2c091662e9fe3d7b2">glfwDestroyWindow</a>.</p>
<div class="fragment"><div class="line"><a class="code" href="group__window.html#gacdf43e51376051d2c091662e9fe3d7b2">glfwDestroyWindow</a>(window);</div></div><!-- fragment --><p>Window destruction always succeeds. Before the actual destruction, all callbacks are removed so no further events will be delivered for the window. All windows remaining when <a class="el" href="group__init.html#gaaae48c0a18607ea4a4ba951d939f0901">glfwTerminate</a> is called are destroyed as well.</p>
<p>When a full screen window is destroyed, the original video mode of its monitor is restored, but the gamma ramp is left untouched.</p>
<h2><a class="anchor" id="window_hints"></a>
Window creation hints</h2>
<p>There are a number of hints that can be set before the creation of a window and context. Some affect the window itself, others affect the framebuffer or context. These hints are set to their default values each time the library is initialized with <a class="el" href="group__init.html#ga317aac130a235ab08c6db0834907d85e">glfwInit</a>, can be set individually with <a class="el" href="group__window.html#ga7d9c8c62384b1e2821c4dc48952d2033">glfwWindowHint</a> and reset all at once to their defaults with <a class="el" href="group__window.html#gaa77c4898dfb83344a6b4f76aa16b9a4a">glfwDefaultWindowHints</a>.</p>
<p>Note that hints need to be set <em>before</em> the creation of the window and context you wish to have the specified attributes.</p>
<h3><a class="anchor" id="window_hints_hard"></a>
Hard and soft constraints</h3>
<p>Some window hints are hard constraints. These must match the available capabilities <em>exactly</em> for window and context creation to succeed. Hints that are not hard constraints are matched as closely as possible, but the resulting context and framebuffer may differ from what these hints requested.</p>
<p>The following hints are always hard constraints:</p><ul>
<li><code>GLFW_STEREO</code></li>
<li><code>GLFW_DOUBLEBUFFER</code></li>
<li><code>GLFW_CLIENT_API</code></li>
<li><code>GLFW_CONTEXT_CREATION_API</code></li>
</ul>
<p>The following additional hints are hard constraints when requesting an OpenGL context, but are ignored when requesting an OpenGL ES context:</p><ul>
<li><code>GLFW_OPENGL_FORWARD_COMPAT</code></li>
<li><code>GLFW_OPENGL_PROFILE</code></li>
</ul>
<h3><a class="anchor" id="window_hints_wnd"></a>
Window related hints</h3>
<p><code>GLFW_RESIZABLE</code> specifies whether the windowed mode window will be resizable <em>by the user</em>. The window will still be resizable using the <a class="el" href="group__window.html#ga371911f12c74c504dd8d47d832d095cb">glfwSetWindowSize</a> function. This hint is ignored for full screen windows.</p>
<p><code>GLFW_VISIBLE</code> specifies whether the windowed mode window will be initially visible. This hint is ignored for full screen windows.</p>
<p><code>GLFW_DECORATED</code> specifies whether the windowed mode window will have window decorations such as a border, a close widget, etc. An undecorated window may still allow the user to generate close events on some platforms. This hint is ignored for full screen windows.</p>
<p><code>GLFW_FOCUSED</code> specifies whether the windowed mode window will be given input focus when created. This hint is ignored for full screen and initially hidden windows.</p>
<p><code>GLFW_AUTO_ICONIFY</code> specifies whether the full screen window will automatically iconify and restore the previous video mode on input focus loss. This hint is ignored for windowed mode windows.</p>
<p><code>GLFW_FLOATING</code> specifies whether the windowed mode window will be floating above other regular windows, also called topmost or always-on-top. This is intended primarily for debugging purposes and cannot be used to implement proper full screen windows. This hint is ignored for full screen windows.</p>
<p><code>GLFW_MAXIMIZED</code> specifies whether the windowed mode window will be maximized when created. This hint is ignored for full screen windows.</p>
<h3><a class="anchor" id="window_hints_fb"></a>
Framebuffer related hints</h3>
<p><code>GLFW_RED_BITS</code>, <code>GLFW_GREEN_BITS</code>, <code>GLFW_BLUE_BITS</code>, <code>GLFW_ALPHA_BITS</code>, <code>GLFW_DEPTH_BITS</code> and <code>GLFW_STENCIL_BITS</code> specify the desired bit depths of the various components of the default framebuffer. <code>GLFW_DONT_CARE</code> means the application has no preference.</p>
<p><code>GLFW_ACCUM_RED_BITS</code>, <code>GLFW_ACCUM_GREEN_BITS</code>, <code>GLFW_ACCUM_BLUE_BITS</code> and <code>GLFW_ACCUM_ALPHA_BITS</code> specify the desired bit depths of the various components of the accumulation buffer. <code>GLFW_DONT_CARE</code> means the application has no preference.</p>
<dl class="section user"><dt></dt><dd>Accumulation buffers are a legacy OpenGL feature and should not be used in new code.</dd></dl>
<p><code>GLFW_AUX_BUFFERS</code> specifies the desired number of auxiliary buffers. <code>GLFW_DONT_CARE</code> means the application has no preference.</p>
<dl class="section user"><dt></dt><dd>Auxiliary buffers are a legacy OpenGL feature and should not be used in new code.</dd></dl>
<p><code>GLFW_STEREO</code> specifies whether to use stereoscopic rendering. This is a hard constraint.</p>
<p><code>GLFW_SAMPLES</code> specifies the desired number of samples to use for multisampling. Zero disables multisampling. <code>GLFW_DONT_CARE</code> means the application has no preference.</p>
<p><code>GLFW_SRGB_CAPABLE</code> specifies whether the framebuffer should be sRGB capable. If supported, a created OpenGL context will support the <code>GL_FRAMEBUFFER_SRGB</code> enable, also called <code>GL_FRAMEBUFFER_SRGB_EXT</code>) for controlling sRGB rendering and a created OpenGL ES context will always have sRGB rendering enabled.</p>
<p><code>GLFW_DOUBLEBUFFER</code> specifies whether the framebuffer should be double buffered. You nearly always want to use double buffering. This is a hard constraint.</p>
<h3><a class="anchor" id="window_hints_mtr"></a>
Monitor related hints</h3>
<p><code>GLFW_REFRESH_RATE</code> specifies the desired refresh rate for full screen windows. If set to <code>GLFW_DONT_CARE</code>, the highest available refresh rate will be used. This hint is ignored for windowed mode windows.</p>
<h3><a class="anchor" id="window_hints_ctx"></a>
Context related hints</h3>
<p><code>GLFW_CLIENT_API</code> specifies which client API to create the context for. Possible values are <code>GLFW_OPENGL_API</code>, <code>GLFW_OPENGL_ES_API</code> and <code>GLFW_NO_API</code>. This is a hard constraint.</p>
<p><code>GLFW_CONTEXT_CREATION_API</code> specifies which context creation API to use to create the context. Possible values are <code>GLFW_NATIVE_CONTEXT_API</code> and <code>GLFW_EGL_CONTEXT_API</code>. This is a hard constraint. If no client API is requested, this hint is ignored.</p>
<dl class="section user"><dt></dt><dd><b>OS X:</b> The EGL API is not available on this platform and requests to use it will fail.</dd></dl>
<dl class="section user"><dt></dt><dd><b>Wayland, Mir:</b> The EGL API <em>is</em> the native context creation API, so this hint will have no effect.</dd></dl>
<dl class="section note"><dt>Note</dt><dd>An OpenGL extension loader library that assumes it knows which context creation API is used on a given platform may fail if you change this hint. This can be resolved by having it load via <a class="el" href="group__context.html#ga35f1837e6f666781842483937612f163">glfwGetProcAddress</a>, which always uses the selected API.</dd></dl>
<dl class="bug"><dt><b><a class="el" href="bug.html#_bug000001">Bug:</a></b></dt><dd>On some Linux systems, creating contexts via both the native and EGL APIs in a single process will cause the application to segfault. Stick to one API or the other on Linux for now.</dd></dl>
<p><code>GLFW_CONTEXT_VERSION_MAJOR</code> and <code>GLFW_CONTEXT_VERSION_MINOR</code> specify the client API version that the created context must be compatible with. The exact behavior of these hints depend on the requested client API.</p>
<dl class="section user"><dt></dt><dd><b>OpenGL:</b> <code>GLFW_CONTEXT_VERSION_MAJOR</code> and <code>GLFW_CONTEXT_VERSION_MINOR</code> are not hard constraints, but creation will fail if the OpenGL version of the created context is less than the one requested. It is therefore perfectly safe to use the default of version 1.0 for legacy code and you will still get backwards-compatible contexts of version 3.0 and above when available.</dd></dl>
<dl class="section user"><dt></dt><dd>While there is no way to ask the driver for a context of the highest supported version, GLFW will attempt to provide this when you ask for a version 1.0 context, which is the default for these hints.</dd></dl>
<dl class="section user"><dt></dt><dd><b>OpenGL ES:</b> <code>GLFW_CONTEXT_VERSION_MAJOR</code> and <code>GLFW_CONTEXT_VERSION_MINOR</code> are not hard constraints, but creation will fail if the OpenGL ES version of the created context is less than the one requested. Additionally, OpenGL ES 1.x cannot be returned if 2.0 or later was requested, and vice versa. This is because OpenGL ES 3.x is backward compatible with 2.0, but OpenGL ES 2.0 is not backward compatible with 1.x.</dd></dl>
<p><code>GLFW_OPENGL_FORWARD_COMPAT</code> specifies whether the OpenGL context should be forward-compatible, i.e. one where all functionality deprecated in the requested version of OpenGL is removed. This must only be used if the requested OpenGL version is 3.0 or above. If OpenGL ES is requested, this hint is ignored.</p>
<dl class="section user"><dt></dt><dd>Forward-compatibility is described in detail in the <a href="https://www.opengl.org/registry/">OpenGL Reference Manual</a>.</dd></dl>
<p><code>GLFW_OPENGL_DEBUG_CONTEXT</code> specifies whether to create a debug OpenGL context, which may have additional error and performance issue reporting functionality. If OpenGL ES is requested, this hint is ignored.</p>
<p><code>GLFW_OPENGL_PROFILE</code> specifies which OpenGL profile to create the context for. Possible values are one of <code>GLFW_OPENGL_CORE_PROFILE</code> or <code>GLFW_OPENGL_COMPAT_PROFILE</code>, or <code>GLFW_OPENGL_ANY_PROFILE</code> to not request a specific profile. If requesting an OpenGL version below 3.2, <code>GLFW_OPENGL_ANY_PROFILE</code> must be used. If OpenGL ES is requested, this hint is ignored.</p>
<dl class="section user"><dt></dt><dd>OpenGL profiles are described in detail in the <a href="https://www.opengl.org/registry/">OpenGL Reference Manual</a>.</dd></dl>
<p><code>GLFW_CONTEXT_ROBUSTNESS</code> specifies the robustness strategy to be used by the context. This can be one of <code>GLFW_NO_RESET_NOTIFICATION</code> or <code>GLFW_LOSE_CONTEXT_ON_RESET</code>, or <code>GLFW_NO_ROBUSTNESS</code> to not request a robustness strategy.</p>
<p><code>GLFW_CONTEXT_RELEASE_BEHAVIOR</code> specifies the release behavior to be used by the context. Possible values are one of <code>GLFW_ANY_RELEASE_BEHAVIOR</code>, <code>GLFW_RELEASE_BEHAVIOR_FLUSH</code> or <code>GLFW_RELEASE_BEHAVIOR_NONE</code>. If the behavior is <code>GLFW_ANY_RELEASE_BEHAVIOR</code>, the default behavior of the context creation API will be used. If the behavior is <code>GLFW_RELEASE_BEHAVIOR_FLUSH</code>, the pipeline will be flushed whenever the context is released from being the current one. If the behavior is <code>GLFW_RELEASE_BEHAVIOR_NONE</code>, the pipeline will not be flushed on release.</p>
<dl class="section user"><dt></dt><dd>Context release behaviors are described in detail by the <a href="https://www.opengl.org/registry/specs/KHR/context_flush_control.txt">GL_KHR_context_flush_control</a> extension.</dd></dl>
<p><code>GLFW_CONTEXT_NO_ERROR</code> specifies whether errors should be generated by the context. If enabled, situations that would have generated errors instead cause undefined behavior.</p>
<dl class="section user"><dt></dt><dd>The no error mode for OpenGL and OpenGL ES is described in detail by the <a href="https://www.opengl.org/registry/specs/KHR/no_error.txt">GL_KHR_no_error</a> extension.</dd></dl>
<dl class="section note"><dt>Note</dt><dd>This hint is experimental in its current state. There are currently (October 2015) no corresponding WGL or GLX extensions. That makes this hint a <a class="el" href="window_guide.html#window_hints_hard">hard constraint</a> for those backends, as creation will fail if unsupported context flags are requested. Once the extensions are available, they will be required and creation of <code>GL_KHR_no_error</code> contexts may fail on early drivers where this flag is supported without those extensions being listed.</dd></dl>
<h3><a class="anchor" id="window_hints_values"></a>
Supported and default values</h3>
<table class="doxtable">
<tr>
<th>Window hint </th><th>Default value </th><th>Supported values  </th></tr>
<tr>
<td><code>GLFW_RESIZABLE</code> </td><td><code>GLFW_TRUE</code> </td><td><code>GLFW_TRUE</code> or <code>GLFW_FALSE</code> </td></tr>
<tr>
<td><code>GLFW_VISIBLE</code> </td><td><code>GLFW_TRUE</code> </td><td><code>GLFW_TRUE</code> or <code>GLFW_FALSE</code> </td></tr>
<tr>
<td><code>GLFW_DECORATED</code> </td><td><code>GLFW_TRUE</code> </td><td><code>GLFW_TRUE</code> or <code>GLFW_FALSE</code> </td></tr>
<tr>
<td><code>GLFW_FOCUSED</code> </td><td><code>GLFW_TRUE</code> </td><td><code>GLFW_TRUE</code> or <code>GLFW_FALSE</code> </td></tr>
<tr>
<td><code>GLFW_AUTO_ICONIFY</code> </td><td><code>GLFW_TRUE</code> </td><td><code>GLFW_TRUE</code> or <code>GLFW_FALSE</code> </td></tr>
<tr>
<td><code>GLFW_FLOATING</code> </td><td><code>GLFW_FALSE</code> </td><td><code>GLFW_TRUE</code> or <code>GLFW_FALSE</code> </td></tr>
<tr>
<td><code>GLFW_MAXIMIZED</code> </td><td><code>GLFW_FALSE</code> </td><td><code>GLFW_TRUE</code> or <code>GLFW_FALSE</code> </td></tr>
<tr>
<td><code>GLFW_RED_BITS</code> </td><td>8 </td><td>0 to <code>INT_MAX</code> or <code>GLFW_DONT_CARE</code> </td></tr>
<tr>
<td><code>GLFW_GREEN_BITS</code> </td><td>8 </td><td>0 to <code>INT_MAX</code> or <code>GLFW_DONT_CARE</code> </td></tr>
<tr>
<td><code>GLFW_BLUE_BITS</code> </td><td>8 </td><td>0 to <code>INT_MAX</code> or <code>GLFW_DONT_CARE</code> </td></tr>
<tr>
<td><code>GLFW_ALPHA_BITS</code> </td><td>8 </td><td>0 to <code>INT_MAX</code> or <code>GLFW_DONT_CARE</code> </td></tr>
<tr>
<td><code>GLFW_DEPTH_BITS</code> </td><td>24 </td><td>0 to <code>INT_MAX</code> or <code>GLFW_DONT_CARE</code> </td></tr>
<tr>
<td><code>GLFW_STENCIL_BITS</code> </td><td>8 </td><td>0 to <code>INT_MAX</code> or <code>GLFW_DONT_CARE</code> </td></tr>
<tr>
<td><code>GLFW_ACCUM_RED_BITS</code> </td><td>0 </td><td>0 to <code>INT_MAX</code> or <code>GLFW_DONT_CARE</code> </td></tr>
<tr>
<td><code>GLFW_ACCUM_GREEN_BITS</code> </td><td>0 </td><td>0 to <code>INT_MAX</code> or <code>GLFW_DONT_CARE</code> </td></tr>
<tr>
<td><code>GLFW_ACCUM_BLUE_BITS</code> </td><td>0 </td><td>0 to <code>INT_MAX</code> or <code>GLFW_DONT_CARE</code> </td></tr>
<tr>
<td><code>GLFW_ACCUM_ALPHA_BITS</code> </td><td>0 </td><td>0 to <code>INT_MAX</code> or <code>GLFW_DONT_CARE</code> </td></tr>
<tr>
<td><code>GLFW_AUX_BUFFERS</code> </td><td>0 </td><td>0 to <code>INT_MAX</code> or <code>GLFW_DONT_CARE</code> </td></tr>
<tr>
<td><code>GLFW_SAMPLES</code> </td><td>0 </td><td>0 to <code>INT_MAX</code> or <code>GLFW_DONT_CARE</code> </td></tr>
<tr>
<td><code>GLFW_REFRESH_RATE</code> </td><td><code>GLFW_DONT_CARE</code> </td><td>0 to <code>INT_MAX</code> or <code>GLFW_DONT_CARE</code> </td></tr>
<tr>
<td><code>GLFW_STEREO</code> </td><td><code>GLFW_FALSE</code> </td><td><code>GLFW_TRUE</code> or <code>GLFW_FALSE</code> </td></tr>
<tr>
<td><code>GLFW_SRGB_CAPABLE</code> </td><td><code>GLFW_FALSE</code> </td><td><code>GLFW_TRUE</code> or <code>GLFW_FALSE</code> </td></tr>
<tr>
<td><code>GLFW_DOUBLEBUFFER</code> </td><td><code>GLFW_TRUE</code> </td><td><code>GLFW_TRUE</code> or <code>GLFW_FALSE</code> </td></tr>
<tr>
<td><code>GLFW_CLIENT_API</code> </td><td><code>GLFW_OPENGL_API</code> </td><td><code>GLFW_OPENGL_API</code>, <code>GLFW_OPENGL_ES_API</code> or <code>GLFW_NO_API</code> </td></tr>
<tr>
<td><code>GLFW_CONTEXT_CREATION_API</code> </td><td><code>GLFW_NATIVE_CONTEXT_API</code> </td><td><code>GLFW_NATIVE_CONTEXT_API</code> or <code>GLFW_EGL_CONTEXT_API</code> </td></tr>
<tr>
<td><code>GLFW_CONTEXT_VERSION_MAJOR</code> </td><td>1 </td><td>Any valid major version number of the chosen client API </td></tr>
<tr>
<td><code>GLFW_CONTEXT_VERSION_MINOR</code> </td><td>0 </td><td>Any valid minor version number of the chosen client API </td></tr>
<tr>
<td><code>GLFW_CONTEXT_ROBUSTNESS</code> </td><td><code>GLFW_NO_ROBUSTNESS</code> </td><td><code>GLFW_NO_ROBUSTNESS</code>, <code>GLFW_NO_RESET_NOTIFICATION</code> or <code>GLFW_LOSE_CONTEXT_ON_RESET</code> </td></tr>
<tr>
<td><code>GLFW_CONTEXT_RELEASE_BEHAVIOR</code> </td><td><code>GLFW_ANY_RELEASE_BEHAVIOR</code> </td><td><code>GLFW_ANY_RELEASE_BEHAVIOR</code>, <code>GLFW_RELEASE_BEHAVIOR_FLUSH</code> or <code>GLFW_RELEASE_BEHAVIOR_NONE</code> </td></tr>
<tr>
<td><code>GLFW_OPENGL_FORWARD_COMPAT</code> </td><td><code>GLFW_FALSE</code> </td><td><code>GLFW_TRUE</code> or <code>GLFW_FALSE</code> </td></tr>
<tr>
<td><code>GLFW_OPENGL_DEBUG_CONTEXT</code> </td><td><code>GLFW_FALSE</code> </td><td><code>GLFW_TRUE</code> or <code>GLFW_FALSE</code> </td></tr>
<tr>
<td><code>GLFW_OPENGL_PROFILE</code> </td><td><code>GLFW_OPENGL_ANY_PROFILE</code> </td><td><code>GLFW_OPENGL_ANY_PROFILE</code>, <code>GLFW_OPENGL_COMPAT_PROFILE</code> or <code>GLFW_OPENGL_CORE_PROFILE</code> </td></tr>
</table>
<h1><a class="anchor" id="window_events"></a>
Window event processing</h1>
<p>See <a class="el" href="input_guide.html#events">Event processing</a>.</p>
<h1><a class="anchor" id="window_properties"></a>
Window properties and events</h1>
<h2><a class="anchor" id="window_userptr"></a>
User pointer</h2>
<p>Each window has a user pointer that can be set with <a class="el" href="group__window.html#ga3d2fc6026e690ab31a13f78bc9fd3651">glfwSetWindowUserPointer</a> and fetched with <a class="el" href="group__window.html#ga17807ce0f45ac3f8bb50d6dcc59a4e06">glfwGetWindowUserPointer</a>. This can be used for any purpose you need and will not be modified by GLFW throughout the life-time of the window.</p>
<p>The initial value of the pointer is <code>NULL</code>.</p>
<h2><a class="anchor" id="window_close"></a>
Window closing and close flag</h2>
<p>When the user attempts to close the window, for example by clicking the close widget or using a key chord like Alt+F4, the <em>close flag</em> of the window is set. The window is however not actually destroyed and, unless you watch for this state change, nothing further happens.</p>
<p>The current state of the close flag is returned by <a class="el" href="group__window.html#ga24e02fbfefbb81fc45320989f8140ab5">glfwWindowShouldClose</a> and can be set or cleared directly with <a class="el" href="group__window.html#ga49c449dde2a6f87d996f4daaa09d6708">glfwSetWindowShouldClose</a>. A common pattern is to use the close flag as a main loop condition.</p>
<div class="fragment"><div class="line"><span class="keywordflow">while</span> (!<a class="code" href="group__window.html#ga24e02fbfefbb81fc45320989f8140ab5">glfwWindowShouldClose</a>(window))</div><div class="line">{</div><div class="line">    render(window);</div><div class="line"></div><div class="line">    <a class="code" href="group__window.html#ga15a5a1ee5b3c2ca6b15ca209a12efd14">glfwSwapBuffers</a>(window);</div><div class="line">    <a class="code" href="group__window.html#ga37bd57223967b4211d60ca1a0bf3c832">glfwPollEvents</a>();</div><div class="line">}</div></div><!-- fragment --><p>If you wish to be notified when the user attempts to close a window, set a close callback.</p>
<div class="fragment"><div class="line"><a class="code" href="group__window.html#gaade9264e79fae52bdb78e2df11ee8d6a">glfwSetWindowCloseCallback</a>(window, window_close_callback);</div></div><!-- fragment --><p>The callback function is called directly <em>after</em> the close flag has been set. It can be used for example to filter close requests and clear the close flag again unless certain conditions are met.</p>
<div class="fragment"><div class="line"><span class="keywordtype">void</span> window_close_callback(<a class="code" href="group__window.html#ga3c96d80d363e67d13a41b5d1821f3242">GLFWwindow</a>* window)</div><div class="line">{</div><div class="line">    <span class="keywordflow">if</span> (!time_to_close)</div><div class="line">        <a class="code" href="group__window.html#ga49c449dde2a6f87d996f4daaa09d6708">glfwSetWindowShouldClose</a>(window, <a class="code" href="glfw3_8h.html#ac877fe3b627d21ef3a0a23e0a73ba8c5">GLFW_FALSE</a>);</div><div class="line">}</div></div><!-- fragment --><h2><a class="anchor" id="window_size"></a>
Window size</h2>
<p>The size of a window can be changed with <a class="el" href="group__window.html#ga371911f12c74c504dd8d47d832d095cb">glfwSetWindowSize</a>. For windowed mode windows, this sets the size, in <a class="el" href="intro_guide.html#coordinate_systems">screen coordinates</a> of the <em>client area</em> or <em>content area</em> of the window. The window system may impose limits on window size.</p>
<div class="fragment"><div class="line"><a class="code" href="group__window.html#ga371911f12c74c504dd8d47d832d095cb">glfwSetWindowSize</a>(window, 640, 480);</div></div><!-- fragment --><p>For full screen windows, the specified size becomes the new resolution of the window's desired video mode. The video mode most closely matching the new desired video mode is set immediately. The window is resized to fit the resolution of the set video mode.</p>
<p>If you wish to be notified when a window is resized, whether by the user or the system, set a size callback.</p>
<div class="fragment"><div class="line"><a class="code" href="group__window.html#gaa40cd24840daa8c62f36cafc847c72b6">glfwSetWindowSizeCallback</a>(window, window_size_callback);</div></div><!-- fragment --><p>The callback function receives the new size, in screen coordinates, of the client area of the window when it is resized.</p>
<div class="fragment"><div class="line"><span class="keywordtype">void</span> window_size_callback(<a class="code" href="group__window.html#ga3c96d80d363e67d13a41b5d1821f3242">GLFWwindow</a>* window, <span class="keywordtype">int</span> width, <span class="keywordtype">int</span> height)</div><div class="line">{</div><div class="line">}</div></div><!-- fragment --><p>There is also <a class="el" href="group__window.html#gaeea7cbc03373a41fb51cfbf9f2a5d4c6">glfwGetWindowSize</a> for directly retrieving the current size of a window.</p>
<div class="fragment"><div class="line"><span class="keywordtype">int</span> width, height;</div><div class="line"><a class="code" href="group__window.html#gaeea7cbc03373a41fb51cfbf9f2a5d4c6">glfwGetWindowSize</a>(window, &amp;width, &amp;height);</div></div><!-- fragment --><dl class="section note"><dt>Note</dt><dd>Do not pass the window size to <code>glViewport</code> or other pixel-based OpenGL calls. The window size is in screen coordinates, not pixels. Use the <a class="el" href="window_guide.html#window_fbsize">framebuffer size</a>, which is in pixels, for pixel-based calls.</dd></dl>
<p>The above functions work with the size of the client area, but decorated windows typically have title bars and window frames around this rectangle. You can retrieve the extents of these with <a class="el" href="group__window.html#ga1a9fd382058c53101b21cf211898f1f1">glfwGetWindowFrameSize</a>.</p>
<div class="fragment"><div class="line"><span class="keywordtype">int</span> left, top, right, bottom;</div><div class="line"><a class="code" href="group__window.html#ga1a9fd382058c53101b21cf211898f1f1">glfwGetWindowFrameSize</a>(window, &amp;left, &amp;top, &amp;right, &amp;bottom);</div></div><!-- fragment --><p>The returned values are the distances, in screen coordinates, from the edges of the client area to the corresponding edges of the full window. As they are distances and not coordinates, they are always zero or positive.</p>
<h2><a class="anchor" id="window_fbsize"></a>
Framebuffer size</h2>
<p>While the size of a window is measured in screen coordinates, OpenGL works with pixels. The size you pass into <code>glViewport</code>, for example, should be in pixels. On some machines screen coordinates and pixels are the same, but on others they will not be. There is a second set of functions to retrieve the size, in pixels, of the framebuffer of a window.</p>
<p>If you wish to be notified when the framebuffer of a window is resized, whether by the user or the system, set a size callback.</p>
<div class="fragment"><div class="line"><a class="code" href="group__window.html#ga3203461a5303bf289f2e05f854b2f7cf">glfwSetFramebufferSizeCallback</a>(window, framebuffer_size_callback);</div></div><!-- fragment --><p>The callback function receives the new size of the framebuffer when it is resized, which can for example be used to update the OpenGL viewport.</p>
<div class="fragment"><div class="line"><span class="keywordtype">void</span> framebuffer_size_callback(<a class="code" href="group__window.html#ga3c96d80d363e67d13a41b5d1821f3242">GLFWwindow</a>* window, <span class="keywordtype">int</span> width, <span class="keywordtype">int</span> height)</div><div class="line">{</div><div class="line">    glViewport(0, 0, width, height);</div><div class="line">}</div></div><!-- fragment --><p>There is also <a class="el" href="group__window.html#ga0e2637a4161afb283f5300c7f94785c9">glfwGetFramebufferSize</a> for directly retrieving the current size of the framebuffer of a window.</p>
<div class="fragment"><div class="line"><span class="keywordtype">int</span> width, height;</div><div class="line"><a class="code" href="group__window.html#ga0e2637a4161afb283f5300c7f94785c9">glfwGetFramebufferSize</a>(window, &amp;width, &amp;height);</div><div class="line">glViewport(0, 0, width, height);</div></div><!-- fragment --><p>The size of a framebuffer may change independently of the size of a window, for example if the window is dragged between a regular monitor and a high-DPI one.</p>
<h2><a class="anchor" id="window_sizelimits"></a>
Window size limits</h2>
<p>The minimum and maximum size of the client area of a windowed mode window can be enforced with <a class="el" href="group__window.html#gac314fa6cec7d2d307be9963e2709cc90">glfwSetWindowSizeLimits</a>. The user may resize the window to any size and aspect ratio within the specified limits, unless the aspect ratio is also set.</p>
<div class="fragment"><div class="line"><a class="code" href="group__window.html#gac314fa6cec7d2d307be9963e2709cc90">glfwSetWindowSizeLimits</a>(window, 200, 200, 400, 400);</div></div><!-- fragment --><p>To specify only a minimum size or only a maximum one, set the other pair to <code>GLFW_DONT_CARE</code>.</p>
<div class="fragment"><div class="line"><a class="code" href="group__window.html#gac314fa6cec7d2d307be9963e2709cc90">glfwSetWindowSizeLimits</a>(window, 640, 480, <a class="code" href="glfw3_8h.html#a7a2edf2c18446833d27d07f1b7f3d571">GLFW_DONT_CARE</a>, <a class="code" href="glfw3_8h.html#a7a2edf2c18446833d27d07f1b7f3d571">GLFW_DONT_CARE</a>);</div></div><!-- fragment --><p>To disable size limits for a window, set them all to <code>GLFW_DONT_CARE</code>.</p>
<p>The aspect ratio of the client area of a windowed mode window can be enforced with <a class="el" href="group__window.html#ga72ac8cb1ee2e312a878b55153d81b937">glfwSetWindowAspectRatio</a>. The user may resize the window freely unless size limits are also set, but the size will be constrained to maintain the aspect ratio.</p>
<div class="fragment"><div class="line"><a class="code" href="group__window.html#ga72ac8cb1ee2e312a878b55153d81b937">glfwSetWindowAspectRatio</a>(window, 16, 9);</div></div><!-- fragment --><p>The aspect ratio is specified as a numerator and denominator, corresponding to the width and height, respectively. If you want a window to maintain its current aspect ratio, simply use its current size as the ratio.</p>
<div class="fragment"><div class="line"><span class="keywordtype">int</span> width, height;</div><div class="line"><a class="code" href="group__window.html#gaeea7cbc03373a41fb51cfbf9f2a5d4c6">glfwGetWindowSize</a>(window, &amp;width, &amp;height);</div><div class="line"><a class="code" href="group__window.html#ga72ac8cb1ee2e312a878b55153d81b937">glfwSetWindowAspectRatio</a>(window, width, height);</div></div><!-- fragment --><p>To disable the aspect ratio limit for a window, set both terms to <code>GLFW_DONT_CARE</code>.</p>
<p>You can have both size limits and aspect ratio set for a window, but the results are undefined if they conflict.</p>
<h2><a class="anchor" id="window_pos"></a>
Window position</h2>
<p>The position of a windowed-mode window can be changed with <a class="el" href="group__window.html#ga1abb6d690e8c88e0c8cd1751356dbca8">glfwSetWindowPos</a>. This moves the window so that the upper-left corner of its client area has the specified <a class="el" href="intro_guide.html#coordinate_systems">screen coordinates</a>. The window system may put limitations on window placement.</p>
<div class="fragment"><div class="line"><a class="code" href="group__window.html#ga1abb6d690e8c88e0c8cd1751356dbca8">glfwSetWindowPos</a>(window, 100, 100);</div></div><!-- fragment --><p>If you wish to be notified when a window is moved, whether by the user, system or your own code, set a position callback.</p>
<div class="fragment"><div class="line"><a class="code" href="group__window.html#ga2837d4d240659feb4268fcb6530a6ba1">glfwSetWindowPosCallback</a>(window, window_pos_callback);</div></div><!-- fragment --><p>The callback function receives the new position of the upper-left corner of the client area when the window is moved.</p>
<div class="fragment"><div class="line"><span class="keywordtype">void</span> window_pos_callback(<a class="code" href="group__window.html#ga3c96d80d363e67d13a41b5d1821f3242">GLFWwindow</a>* window, <span class="keywordtype">int</span> xpos, <span class="keywordtype">int</span> ypos)</div><div class="line">{</div><div class="line">}</div></div><!-- fragment --><p>There is also <a class="el" href="group__window.html#ga73cb526c000876fd8ddf571570fdb634">glfwGetWindowPos</a> for directly retrieving the current position of the client area of the window.</p>
<div class="fragment"><div class="line"><span class="keywordtype">int</span> xpos, ypos;</div><div class="line"><a class="code" href="group__window.html#ga73cb526c000876fd8ddf571570fdb634">glfwGetWindowPos</a>(window, &amp;xpos, &amp;ypos);</div></div><!-- fragment --><h2><a class="anchor" id="window_title"></a>
Window title</h2>
<p>All GLFW windows have a title, although undecorated or full screen windows may not display it or only display it in a task bar or similar interface. You can set a UTF-8 encoded window title with <a class="el" href="group__window.html#ga5d877f09e968cef7a360b513306f17ff">glfwSetWindowTitle</a>.</p>
<div class="fragment"><div class="line"><a class="code" href="group__window.html#ga5d877f09e968cef7a360b513306f17ff">glfwSetWindowTitle</a>(window, <span class="stringliteral">&quot;My Window&quot;</span>);</div></div><!-- fragment --><p>The specified string is copied before the function returns, so there is no need to keep it around.</p>
<p>As long as your source file is encoded as UTF-8, you can use any Unicode characters directly in the source.</p>
<div class="fragment"><div class="line"><a class="code" href="group__window.html#ga5d877f09e968cef7a360b513306f17ff">glfwSetWindowTitle</a>(window, <span class="stringliteral">&quot;カウボーイビバップ&quot;</span>);</div></div><!-- fragment --><p>If you are using C++11 or C11, you can use a UTF-8 string literal.</p>
<div class="fragment"><div class="line"><a class="code" href="group__window.html#ga5d877f09e968cef7a360b513306f17ff">glfwSetWindowTitle</a>(window, u8<span class="stringliteral">&quot;This is always a UTF-8 string&quot;</span>);</div></div><!-- fragment --><h2><a class="anchor" id="window_icon"></a>
Window icon</h2>
<p>Decorated windows have icons on some platforms. You can set this icon by specifying a list of candidate images with <a class="el" href="group__window.html#gadd7ccd39fe7a7d1f0904666ae5932dc5">glfwSetWindowIcon</a>.</p>
<div class="fragment"><div class="line"><a class="code" href="structGLFWimage.html">GLFWimage</a> images[2];</div><div class="line">images[0] = load_icon(<span class="stringliteral">&quot;my_icon.png&quot;</span>);</div><div class="line">images[1] = load_icon(<span class="stringliteral">&quot;my_icon_small.png&quot;</span>);</div><div class="line"></div><div class="line"><a class="code" href="group__window.html#gadd7ccd39fe7a7d1f0904666ae5932dc5">glfwSetWindowIcon</a>(window, 2, images);</div></div><!-- fragment --><p>To revert to the default window icon, pass in an empty image array.</p>
<div class="fragment"><div class="line"><a class="code" href="group__window.html#gadd7ccd39fe7a7d1f0904666ae5932dc5">glfwSetWindowIcon</a>(window, 0, NULL);</div></div><!-- fragment --><h2><a class="anchor" id="window_monitor"></a>
Window monitor</h2>
<p>Full screen windows are associated with a specific monitor. You can get the handle for this monitor with <a class="el" href="group__window.html#gaeac25e64789974ccbe0811766bd91a16">glfwGetWindowMonitor</a>.</p>
<div class="fragment"><div class="line"><a class="code" href="group__monitor.html#ga8d9efd1cde9426692c73fe40437d0ae3">GLFWmonitor</a>* monitor = <a class="code" href="group__window.html#gaeac25e64789974ccbe0811766bd91a16">glfwGetWindowMonitor</a>(window);</div></div><!-- fragment --><p>This monitor handle is one of those returned by <a class="el" href="group__monitor.html#ga3fba51c8bd36491d4712aa5bd074a537">glfwGetMonitors</a>.</p>
<p>For windowed mode windows, this function returns <code>NULL</code>. This is how to tell full screen windows from windowed mode windows.</p>
<p>You can move windows between monitors or between full screen and windowed mode with <a class="el" href="group__window.html#ga81c76c418af80a1cce7055bccb0ae0a7">glfwSetWindowMonitor</a>. When making a window full screen on the same or on a different monitor, specify the desired monitor, resolution and refresh rate. The position arguments are ignored.</p>
<div class="fragment"><div class="line"><span class="keyword">const</span> <a class="code" href="structGLFWvidmode.html">GLFWvidmode</a>* mode = <a class="code" href="group__monitor.html#gafc1bb972a921ad5b3bd5d63a95fc2d52">glfwGetVideoMode</a>(monitor);</div><div class="line"></div><div class="line"><a class="code" href="group__window.html#ga81c76c418af80a1cce7055bccb0ae0a7">glfwSetWindowMonitor</a>(window, monitor, 0, 0, mode-&gt;<a class="code" href="structGLFWvidmode.html#a698dcb200562051a7249cb6ae154c71d">width</a>, mode-&gt;<a class="code" href="structGLFWvidmode.html#ac65942a5f6981695517437a9d571d03c">height</a>, mode-&gt;<a class="code" href="structGLFWvidmode.html#a791bdd6c7697b09f7e9c97054bf05649">refreshRate</a>);</div></div><!-- fragment --><p>When making the window windowed, specify the desired position and size. The refresh rate argument is ignored.</p>
<div class="fragment"><div class="line"><a class="code" href="group__window.html#ga81c76c418af80a1cce7055bccb0ae0a7">glfwSetWindowMonitor</a>(window, NULL, xpos, ypos, width, height, 0);</div></div><!-- fragment --><p>This restores any previous window settings such as whether it is decorated, floating, resizable, has size or aspect ratio limits, etc.. To restore a window that was originally windowed to its original size and position, save these before making it full screen and then pass them in as above.</p>
<h2><a class="anchor" id="window_iconify"></a>
Window iconification</h2>
<p>Windows can be iconified (i.e. minimized) with <a class="el" href="group__window.html#ga1bb559c0ebaad63c5c05ad2a066779c4">glfwIconifyWindow</a>.</p>
<div class="fragment"><div class="line"><a class="code" href="group__window.html#ga1bb559c0ebaad63c5c05ad2a066779c4">glfwIconifyWindow</a>(window);</div></div><!-- fragment --><p>When a full screen window is iconified, the original video mode of its monitor is restored until the user or application restores the window.</p>
<p>Iconified windows can be restored with <a class="el" href="group__window.html#ga52527a5904b47d802b6b4bb519cdebc7">glfwRestoreWindow</a>.</p>
<div class="fragment"><div class="line"><a class="code" href="group__window.html#ga52527a5904b47d802b6b4bb519cdebc7">glfwRestoreWindow</a>(window);</div></div><!-- fragment --><p>When a full screen window is restored, the desired video mode is restored to its monitor as well.</p>
<p>If you wish to be notified when a window is iconified or restored, whether by the user, system or your own code, set a iconify callback.</p>
<div class="fragment"><div class="line"><a class="code" href="group__window.html#gab1ea7263081c0e073b8d5b91d6ffd367">glfwSetWindowIconifyCallback</a>(window, window_iconify_callback);</div></div><!-- fragment --><p>The callback function receives changes in the iconification state of the window.</p>
<div class="fragment"><div class="line"><span class="keywordtype">void</span> window_iconify_callback(<a class="code" href="group__window.html#ga3c96d80d363e67d13a41b5d1821f3242">GLFWwindow</a>* window, <span class="keywordtype">int</span> iconified)</div><div class="line">{</div><div class="line">    <span class="keywordflow">if</span> (iconified)</div><div class="line">    {</div><div class="line">        <span class="comment">// The window was iconified</span></div><div class="line">    }</div><div class="line">    <span class="keywordflow">else</span></div><div class="line">    {</div><div class="line">        <span class="comment">// The window was restored</span></div><div class="line">    }</div><div class="line">}</div></div><!-- fragment --><p>You can also get the current iconification state with <a class="el" href="group__window.html#gacccb29947ea4b16860ebef42c2cb9337">glfwGetWindowAttrib</a>.</p>
<div class="fragment"><div class="line"><span class="keywordtype">int</span> iconified = <a class="code" href="group__window.html#gacccb29947ea4b16860ebef42c2cb9337">glfwGetWindowAttrib</a>(window, <a class="code" href="glfw3_8h.html#a39d44b7c056e55e581355a92d240b58a">GLFW_ICONIFIED</a>);</div></div><!-- fragment --><h2><a class="anchor" id="window_hide"></a>
Window visibility</h2>
<p>Windowed mode windows can be hidden with <a class="el" href="group__window.html#ga49401f82a1ba5f15db5590728314d47c">glfwHideWindow</a>.</p>
<div class="fragment"><div class="line"><a class="code" href="group__window.html#ga49401f82a1ba5f15db5590728314d47c">glfwHideWindow</a>(window);</div></div><!-- fragment --><p>This makes the window completely invisible to the user, including removing it from the task bar, dock or window list. Full screen windows cannot be hidden and calling <a class="el" href="group__window.html#ga49401f82a1ba5f15db5590728314d47c">glfwHideWindow</a> on a full screen window does nothing.</p>
<p>Hidden windows can be shown with <a class="el" href="group__window.html#ga61be47917b72536a148300f46494fc66">glfwShowWindow</a>.</p>
<div class="fragment"><div class="line"><a class="code" href="group__window.html#ga61be47917b72536a148300f46494fc66">glfwShowWindow</a>(window);</div></div><!-- fragment --><p>Windowed mode windows can be created initially hidden with the <code>GLFW_VISIBLE</code> <a class="el" href="window_guide.html#window_hints_wnd">window hint</a>. Windows created hidden are completely invisible to the user until shown. This can be useful if you need to set up your window further before showing it, for example moving it to a specific location.</p>
<p>You can also get the current visibility state with <a class="el" href="group__window.html#gacccb29947ea4b16860ebef42c2cb9337">glfwGetWindowAttrib</a>.</p>
<div class="fragment"><div class="line"><span class="keywordtype">int</span> visible = <a class="code" href="group__window.html#gacccb29947ea4b16860ebef42c2cb9337">glfwGetWindowAttrib</a>(window, <a class="code" href="glfw3_8h.html#afb3cdc45297e06d8f1eb13adc69ca6c4">GLFW_VISIBLE</a>);</div></div><!-- fragment --><h2><a class="anchor" id="window_focus"></a>
Window input focus</h2>
<p>Windows can be given input focus and brought to the front with <a class="el" href="group__window.html#ga873780357abd3f3a081d71a40aae45a1">glfwFocusWindow</a>.</p>
<div class="fragment"><div class="line"><a class="code" href="group__window.html#ga873780357abd3f3a081d71a40aae45a1">glfwFocusWindow</a>(window);</div></div><!-- fragment --><p>If you wish to be notified when a window gains or loses input focus, whether by the user, system or your own code, set a focus callback.</p>
<div class="fragment"><div class="line"><a class="code" href="group__window.html#ga25d1c584edb375d7711c5c3548ba711f">glfwSetWindowFocusCallback</a>(window, window_focus_callback);</div></div><!-- fragment --><p>The callback function receives changes in the input focus state of the window.</p>
<div class="fragment"><div class="line"><span class="keywordtype">void</span> window_focus_callback(<a class="code" href="group__window.html#ga3c96d80d363e67d13a41b5d1821f3242">GLFWwindow</a>* window, <span class="keywordtype">int</span> focused)</div><div class="line">{</div><div class="line">    <span class="keywordflow">if</span> (focused)</div><div class="line">    {</div><div class="line">        <span class="comment">// The window gained input focus</span></div><div class="line">    }</div><div class="line">    <span class="keywordflow">else</span></div><div class="line">    {</div><div class="line">        <span class="comment">// The window lost input focus</span></div><div class="line">    }</div><div class="line">}</div></div><!-- fragment --><p>You can also get the current input focus state with <a class="el" href="group__window.html#gacccb29947ea4b16860ebef42c2cb9337">glfwGetWindowAttrib</a>.</p>
<div class="fragment"><div class="line"><span class="keywordtype">int</span> focused = <a class="code" href="group__window.html#gacccb29947ea4b16860ebef42c2cb9337">glfwGetWindowAttrib</a>(window, <a class="code" href="glfw3_8h.html#a54ddb14825a1541a56e22afb5f832a9e">GLFW_FOCUSED</a>);</div></div><!-- fragment --><h2><a class="anchor" id="window_refresh"></a>
Window damage and refresh</h2>
<p>If you wish to be notified when the contents of a window is damaged and needs to be refreshed, set a window refresh callback.</p>
<div class="fragment"><div class="line"><a class="code" href="group__window.html#ga4569b76e8ac87c55b53199e6becd97eb">glfwSetWindowRefreshCallback</a>(m_handle, window_refresh_callback);</div></div><!-- fragment --><p>The callback function is called when the contents of the window needs to be refreshed.</p>
<div class="fragment"><div class="line"><span class="keywordtype">void</span> window_refresh_callback(<a class="code" href="group__window.html#ga3c96d80d363e67d13a41b5d1821f3242">GLFWwindow</a>* window)</div><div class="line">{</div><div class="line">    draw_editor_ui(window);</div><div class="line">    <a class="code" href="group__window.html#ga15a5a1ee5b3c2ca6b15ca209a12efd14">glfwSwapBuffers</a>(window);</div><div class="line">}</div></div><!-- fragment --><dl class="section note"><dt>Note</dt><dd>On compositing window systems such as Aero, Compiz or Aqua, where the window contents are saved off-screen, this callback might only be called when the window or framebuffer is resized.</dd></dl>
<h2><a class="anchor" id="window_attribs"></a>
Window attributes</h2>
<p>Windows have a number of attributes that can be returned using <a class="el" href="group__window.html#gacccb29947ea4b16860ebef42c2cb9337">glfwGetWindowAttrib</a>. Some reflect state that may change during the lifetime of the window, while others reflect the corresponding hints and are fixed at the time of creation. Some are related to the actual window and others to its context.</p>
<div class="fragment"><div class="line"><span class="keywordflow">if</span> (<a class="code" href="group__window.html#gacccb29947ea4b16860ebef42c2cb9337">glfwGetWindowAttrib</a>(window, <a class="code" href="glfw3_8h.html#a54ddb14825a1541a56e22afb5f832a9e">GLFW_FOCUSED</a>))</div><div class="line">{</div><div class="line">    <span class="comment">// window has input focus</span></div><div class="line">}</div></div><!-- fragment --><h3><a class="anchor" id="window_attribs_wnd"></a>
Window related attributes</h3>
<p><code>GLFW_FOCUSED</code> indicates whether the specified window has input focus. Initial input focus is controlled by the <a class="el" href="window_guide.html#window_hints_wnd">window hint</a> with the same name.</p>
<p><code>GLFW_ICONIFIED</code> indicates whether the specified window is iconified, whether by the user or with <a class="el" href="group__window.html#ga1bb559c0ebaad63c5c05ad2a066779c4">glfwIconifyWindow</a>.</p>
<p><code>GLFW_MAXIMIZED</code> indicates whether the specified window is maximized, whether by the user or with <a class="el" href="group__window.html#ga3f541387449d911274324ae7f17ec56b">glfwMaximizeWindow</a>.</p>
<p><code>GLFW_VISIBLE</code> indicates whether the specified window is visible. Window visibility can be controlled with <a class="el" href="group__window.html#ga61be47917b72536a148300f46494fc66">glfwShowWindow</a> and <a class="el" href="group__window.html#ga49401f82a1ba5f15db5590728314d47c">glfwHideWindow</a> and initial visibility is controlled by the <a class="el" href="window_guide.html#window_hints_wnd">window hint</a> with the same name.</p>
<p><code>GLFW_RESIZABLE</code> indicates whether the specified window is resizable <em>by the user</em>. This is set on creation with the <a class="el" href="window_guide.html#window_hints_wnd">window hint</a> with the same name.</p>
<p><code>GLFW_DECORATED</code> indicates whether the specified window has decorations such as a border, a close widget, etc. This is set on creation with the <a class="el" href="window_guide.html#window_hints_wnd">window hint</a> with the same name.</p>
<p><code>GLFW_FLOATING</code> indicates whether the specified window is floating, also called topmost or always-on-top. This is controlled by the <a class="el" href="window_guide.html#window_hints_wnd">window hint</a> with the same name.</p>
<h3><a class="anchor" id="window_attribs_ctx"></a>
Context related attributes</h3>
<p><code>GLFW_CLIENT_API</code> indicates the client API provided by the window's context; either <code>GLFW_OPENGL_API</code>, <code>GLFW_OPENGL_ES_API</code> or <code>GLFW_NO_API</code>.</p>
<p><code>GLFW_CONTEXT_CREATION_API</code> indicates the context creation API used to create the window's context; either <code>GLFW_NATIVE_CONTEXT_API</code> or <code>GLFW_EGL_CONTEXT_API</code>.</p>
<p><code>GLFW_CONTEXT_VERSION_MAJOR</code>, <code>GLFW_CONTEXT_VERSION_MINOR</code> and <code>GLFW_CONTEXT_REVISION</code> indicate the client API version of the window's context.</p>
<p><code>GLFW_OPENGL_FORWARD_COMPAT</code> is <code>GLFW_TRUE</code> if the window's context is an OpenGL forward-compatible one, or <code>GLFW_FALSE</code> otherwise.</p>
<p><code>GLFW_OPENGL_DEBUG_CONTEXT</code> is <code>GLFW_TRUE</code> if the window's context is an OpenGL debug context, or <code>GLFW_FALSE</code> otherwise.</p>
<p><code>GLFW_OPENGL_PROFILE</code> indicates the OpenGL profile used by the context. This is <code>GLFW_OPENGL_CORE_PROFILE</code> or <code>GLFW_OPENGL_COMPAT_PROFILE</code> if the context uses a known profile, or <code>GLFW_OPENGL_ANY_PROFILE</code> if the OpenGL profile is unknown or the context is an OpenGL ES context. Note that the returned profile may not match the profile bits of the context flags, as GLFW will try other means of detecting the profile when no bits are set.</p>
<p><code>GLFW_CONTEXT_ROBUSTNESS</code> indicates the robustness strategy used by the context. This is <code>GLFW_LOSE_CONTEXT_ON_RESET</code> or <code>GLFW_NO_RESET_NOTIFICATION</code> if the window's context supports robustness, or <code>GLFW_NO_ROBUSTNESS</code> otherwise.</p>
<h3><a class="anchor" id="window_attribs_fb"></a>
Framebuffer related attributes</h3>
<p>GLFW does not expose attributes of the default framebuffer (i.e. the framebuffer attached to the window) as these can be queried directly with either OpenGL, OpenGL ES or Vulkan.</p>
<p>If you are using version 3.0 or later of OpenGL or OpenGL ES, the <code>glGetFramebufferAttachmentParameteriv</code> function can be used to retrieve the number of bits for the red, green, blue, alpha, depth and stencil buffer channels. Otherwise, the <code>glGetIntegerv</code> function can be used.</p>
<p>The number of MSAA samples are always retrieved with <code>glGetIntegerv</code>. For contexts supporting framebuffer objects, the number of samples of the currently bound framebuffer is returned.</p>
<table class="doxtable">
<tr>
<th>Attribute </th><th>glGetIntegerv </th><th>glGetFramebufferAttachmentParameteriv  </th></tr>
<tr>
<td>Red bits </td><td><code>GL_RED_BITS</code> </td><td><code>GL_FRAMEBUFFER_ATTACHMENT_RED_SIZE</code> </td></tr>
<tr>
<td>Green bits </td><td><code>GL_GREEN_BITS</code> </td><td><code>GL_FRAMEBUFFER_ATTACHMENT_GREEN_SIZE</code> </td></tr>
<tr>
<td>Blue bits </td><td><code>GL_BLUE_BITS</code> </td><td><code>GL_FRAMEBUFFER_ATTACHMENT_BLUE_SIZE</code> </td></tr>
<tr>
<td>Alpha bits </td><td><code>GL_ALPHA_BITS</code> </td><td><code>GL_FRAMEBUFFER_ATTACHMENT_ALPHA_SIZE</code> </td></tr>
<tr>
<td>Depth bits </td><td><code>GL_DEPTH_BITS</code> </td><td><code>GL_FRAMEBUFFER_ATTACHMENT_DEPTH_SIZE</code> </td></tr>
<tr>
<td>Stencil bits </td><td><code>GL_STENCIL_BITS</code> </td><td><code>GL_FRAMEBUFFER_ATTACHMENT_STENCIL_SIZE</code> </td></tr>
<tr>
<td>MSAA samples </td><td><code>GL_SAMPLES</code> </td><td><em>Not provided by this function</em> </td></tr>
</table>
<p>When calling <code>glGetFramebufferAttachmentParameteriv</code>, the red, green, blue and alpha sizes are queried from the <code>GL_BACK_LEFT</code>, while the depth and stencil sizes are queried from the <code>GL_DEPTH</code> and <code>GL_STENCIL</code> attachments, respectively.</p>
<h1><a class="anchor" id="buffer_swap"></a>
Buffer swapping</h1>
<p>GLFW windows are by default double buffered. That means that you have two rendering buffers; a front buffer and a back buffer. The front buffer is the one being displayed and the back buffer the one you render to.</p>
<p>When the entire frame has been rendered, it is time to swap the back and the front buffers in order to display what has been rendered and begin rendering a new frame. This is done with <a class="el" href="group__window.html#ga15a5a1ee5b3c2ca6b15ca209a12efd14">glfwSwapBuffers</a>.</p>
<div class="fragment"><div class="line"><a class="code" href="group__window.html#ga15a5a1ee5b3c2ca6b15ca209a12efd14">glfwSwapBuffers</a>(window);</div></div><!-- fragment --><p>Sometimes it can be useful to select when the buffer swap will occur. With the function <a class="el" href="group__context.html#ga6d4e0cdf151b5e579bd67f13202994ed">glfwSwapInterval</a> it is possible to select the minimum number of monitor refreshes the driver wait should from the time <a class="el" href="group__window.html#ga15a5a1ee5b3c2ca6b15ca209a12efd14">glfwSwapBuffers</a> was called before swapping the buffers:</p>
<div class="fragment"><div class="line"><a class="code" href="group__context.html#ga6d4e0cdf151b5e579bd67f13202994ed">glfwSwapInterval</a>(1);</div></div><!-- fragment --><p>If the interval is zero, the swap will take place immediately when <a class="el" href="group__window.html#ga15a5a1ee5b3c2ca6b15ca209a12efd14">glfwSwapBuffers</a> is called without waiting for a refresh. Otherwise at least interval retraces will pass between each buffer swap. Using a swap interval of zero can be useful for benchmarking purposes, when it is not desirable to measure the time it takes to wait for the vertical retrace. However, a swap interval of one lets you avoid tearing.</p>
<p>Note that this may not work on all machines, as some drivers have user-controlled settings that override any swap interval the application requests. </p>
</div></div><!-- contents -->
<address class="footer">
<p>
Last update on Thu Aug 18 2016 for GLFW 3.2.1
</p>
</address>
</body>
</html>
