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Andreas Boll	ecd5c7c	2012-06-12 09:05:03 +0200	[diff] [blame]	1	<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
				2	<html lang="en">
				3	<head>
				4	<meta http-equiv="content-type" content="text/html; charset=utf-8">
				5	<title>Mesa EGL</title>
				6	<link rel="stylesheet" type="text/css" href="mesa.css">
				7	</head>
Chia-I Wu	ada4605	2010-01-21 15:29:14 +0800	[diff] [blame]	8	<body>
				9
Andreas Boll	b5da52a	2012-09-18 18:57:02 +0200	[diff] [blame]	10	<div class="header">
				11	<h1>The Mesa 3D Graphics Library</h1>
				12	</div>
				13
				14	<iframe src="contents.html"></iframe>
				15	<div class="content">
				16
Chia-I Wu	ada4605	2010-01-21 15:29:14 +0800	[diff] [blame]	17	<h1>Mesa EGL</h1>
				18
				19	<p>The current version of EGL in Mesa implements EGL 1.4. More information
				20	about EGL can be found at
Andreas Boll	a73c59b	2012-09-18 19:31:28 +0200	[diff] [blame]	21	<a href="http://www.khronos.org/egl/">
Brian Paul	aeff9f9	2010-01-21 08:13:32 -0700	[diff] [blame]	22	http://www.khronos.org/egl/</a>.</p>
Chia-I Wu	ada4605	2010-01-21 15:29:14 +0800	[diff] [blame]	23
				24	<p>The Mesa's implementation of EGL uses a driver architecture. The main
				25	library (<code>libEGL</code>) is window system neutral. It provides the EGL
				26	API entry points and helper functions for use by the drivers. Drivers are
				27	dynamically loaded by the main library and most of the EGL API calls are
				28	directly dispatched to the drivers.</p>
				29
Chia-I Wu	65e8f81	2010-12-25 02:45:13 +0800	[diff] [blame]	30	<p>The driver in use decides the window system to support.</p>
Chia-I Wu	ada4605	2010-01-21 15:29:14 +0800	[diff] [blame]	31
				32	<h2>Build EGL</h2>
				33
				34	<ol>
				35	<li>
Chia-I Wu	3418f74	2010-11-02 23:55:56 +0800	[diff] [blame]	36	<p>Run <code>configure</code> with the desired client APIs and enable
				37	the driver for your hardware. For example</p>
Chia-I Wu	ada4605	2010-01-21 15:29:14 +0800	[diff] [blame]	38
				39	<pre>
Chia-I Wu	8eea050	2011-06-20 11:14:56 +0900	[diff] [blame]	40	$ ./configure --enable-gles1 --enable-gles2 \
				41	--with-dri-drivers=... \
				42	--with-gallium-drivers=...
Chia-I Wu	ada4605	2010-01-21 15:29:14 +0800	[diff] [blame]	43	</pre>
				44
Chia-I Wu	8eea050	2011-06-20 11:14:56 +0900	[diff] [blame]	45	<p>The main library and OpenGL is enabled by default. The first two options
				46	above enables <a href="opengles.html">OpenGL ES 1.x and 2.x</a>. The last two
				47	options enables the listed classic and and Gallium drivers respectively.</p>
Chia-I Wu	c6320c5	2010-10-28 17:25:07 +0800	[diff] [blame]	48
Chia-I Wu	ada4605	2010-01-21 15:29:14 +0800	[diff] [blame]	49	</li>
				50
				51	<li>Build and install Mesa as usual.</li>
				52	</ol>
				53
				54	<p>In the given example, it will build and install <code>libEGL</code>,
Chia-I Wu	8eea050	2011-06-20 11:14:56 +0900	[diff] [blame]	55	<code>libGL</code>, <code>libGLESv1_CM</code>, <code>libGLESv2</code>, and one
				56	or more EGL drivers.</p>
Chia-I Wu	ada4605	2010-01-21 15:29:14 +0800	[diff] [blame]	57
				58	<h3>Configure Options</h3>
				59
				60	<p>There are several options that control the build of EGL at configuration
				61	time</p>
				62
Andreas Boll	76d4f9e	2012-09-20 16:01:08 +0200	[diff] [blame]	63	<dl>
				64	<dt><code>--enable-egl</code></dt>
				65	<dd>
Chia-I Wu	ada4605	2010-01-21 15:29:14 +0800	[diff] [blame]	66
				67	<p>By default, EGL is enabled. When disabled, the main library and the drivers
				68	will not be built.</p>
				69
Andreas Boll	76d4f9e	2012-09-20 16:01:08 +0200	[diff] [blame]	70	</dd>
Chia-I Wu	ada4605	2010-01-21 15:29:14 +0800	[diff] [blame]	71
Andreas Boll	76d4f9e	2012-09-20 16:01:08 +0200	[diff] [blame]	72	<dt><code>--with-egl-driver-dir</code></dt>
				73	<dd>
Chia-I Wu	a6342af	2010-01-26 10:54:45 +0800	[diff] [blame]	74
				75	<p>The directory EGL drivers should be installed to. If not specified, EGL
				76	drivers will be installed to <code>${libdir}/egl</code>.</p>
				77
Andreas Boll	76d4f9e	2012-09-20 16:01:08 +0200	[diff] [blame]	78	</dd>
Chia-I Wu	a6342af	2010-01-26 10:54:45 +0800	[diff] [blame]	79
Andreas Boll	76d4f9e	2012-09-20 16:01:08 +0200	[diff] [blame]	80	<dt><code>--enable-gallium-egl</code></dt>
				81	<dd>
Chia-I Wu	8eea050	2011-06-20 11:14:56 +0900	[diff] [blame]	82
				83	<p>Enable the optional <code>egl_gallium</code> driver.</p>
				84
Andreas Boll	76d4f9e	2012-09-20 16:01:08 +0200	[diff] [blame]	85	</dd>
Chia-I Wu	8eea050	2011-06-20 11:14:56 +0900	[diff] [blame]	86
Andreas Boll	76d4f9e	2012-09-20 16:01:08 +0200	[diff] [blame]	87	<dt><code>--with-egl-platforms</code></dt>
				88	<dd>
Chia-I Wu	ada4605	2010-01-21 15:29:14 +0800	[diff] [blame]	89
Chia-I Wu	b365b15	2010-07-03 17:18:40 +0800	[diff] [blame]	90	<p>List the platforms (window systems) to support. Its argument is a comma
Nathan Kidd	0691b37	2014-01-03 16:44:00 -0700	[diff] [blame]	91	separated string such as <code>--with-egl-platforms=x11,drm</code>. It decides
Chia-I Wu	b365b15	2010-07-03 17:18:40 +0800	[diff] [blame]	92	the platforms a driver may support. The first listed platform is also used by
				93	the main library to decide the native platform: the platform the EGL native
				94	types such as <code>EGLNativeDisplayType</code> or
				95	<code>EGLNativeWindowType</code> defined for.</p>
Chia-I Wu	ada4605	2010-01-21 15:29:14 +0800	[diff] [blame]	96
Chia-I Wu	e7424d7	2010-09-19 16:54:39 +0800	[diff] [blame]	97	<p>The available platforms are <code>x11</code>, <code>drm</code>,
Chia-I Wu	da39d5d	2010-06-17 16:07:46 +0800	[diff] [blame]	98	<code>fbdev</code>, and <code>gdi</code>. The <code>gdi</code> platform can
Chia-I Wu	3418f74	2010-11-02 23:55:56 +0800	[diff] [blame]	99	only be built with SCons. Unless for special needs, the build system should
				100	select the right platforms automatically.</p>
Chia-I Wu	2e3c4e4	2010-05-07 14:13:08 +0800	[diff] [blame]	101
Andreas Boll	76d4f9e	2012-09-20 16:01:08 +0200	[diff] [blame]	102	</dd>
Chia-I Wu	2e3c4e4	2010-05-07 14:13:08 +0800	[diff] [blame]	103
Andreas Boll	76d4f9e	2012-09-20 16:01:08 +0200	[diff] [blame]	104	<dt><code>--enable-gles1</code></dt>
				105	<dt><code>--enable-gles2</code></dt>
				106	<dd>
Chia-I Wu	2e3c4e4	2010-05-07 14:13:08 +0800	[diff] [blame]	107
Chia-I Wu	65e8f81	2010-12-25 02:45:13 +0800	[diff] [blame]	108	<p>These options enable OpenGL ES support in OpenGL. The result is one big
				109	internal library that supports multiple APIs.</p>
Chia-I Wu	ada4605	2010-01-21 15:29:14 +0800	[diff] [blame]	110
Andreas Boll	76d4f9e	2012-09-20 16:01:08 +0200	[diff] [blame]	111	</dd>
Chia-I Wu	a1306f4	2010-01-22 15:51:51 +0800	[diff] [blame]	112
Andreas Boll	76d4f9e	2012-09-20 16:01:08 +0200	[diff] [blame]	113	<dt><code>--enable-shared-glapi</code></dt>
				114	<dd>
Chia-I Wu	c6320c5	2010-10-28 17:25:07 +0800	[diff] [blame]	115
Chia-I Wu	8eea050	2011-06-20 11:14:56 +0900	[diff] [blame]	116	<p>By default, <code>libGL</code> has its own copy of <code>libglapi</code>.
				117	This options makes <code>libGL</code> use the shared <code>libglapi</code>. This
				118	is required if applications mix OpenGL and OpenGL ES.</p>
Chia-I Wu	c6320c5	2010-10-28 17:25:07 +0800	[diff] [blame]	119
Andreas Boll	76d4f9e	2012-09-20 16:01:08 +0200	[diff] [blame]	120	</dd>
Chia-I Wu	c6320c5	2010-10-28 17:25:07 +0800	[diff] [blame]	121
Andreas Boll	76d4f9e	2012-09-20 16:01:08 +0200	[diff] [blame]	122	<dt><code>--enable-openvg</code></dt>
				123	<dd>
Chia-I Wu	3418f74	2010-11-02 23:55:56 +0800	[diff] [blame]	124
Chia-I Wu	8eea050	2011-06-20 11:14:56 +0900	[diff] [blame]	125	<p>OpenVG must be explicitly enabled by this option.</p>
Chia-I Wu	3418f74	2010-11-02 23:55:56 +0800	[diff] [blame]	126
Andreas Boll	76d4f9e	2012-09-20 16:01:08 +0200	[diff] [blame]	127	</dd>
Chia-I Wu	3418f74	2010-11-02 23:55:56 +0800	[diff] [blame]	128
Andreas Boll	76d4f9e	2012-09-20 16:01:08 +0200	[diff] [blame]	129	</dl>
Chia-I Wu	ada4605	2010-01-21 15:29:14 +0800	[diff] [blame]	130
Chia-I Wu	ada4605	2010-01-21 15:29:14 +0800	[diff] [blame]	131	<h2>Use EGL</h2>
				132
Chia-I Wu	411bba3	2010-06-11 12:47:14 +0800	[diff] [blame]	133	<h3>Demos</h3>
Chia-I Wu	ada4605	2010-01-21 15:29:14 +0800	[diff] [blame]	134
Chia-I Wu	411bba3	2010-06-11 12:47:14 +0800	[diff] [blame]	135	<p>There are demos for the client APIs supported by EGL. They can be found in
				136	mesa/demos repository.</p>
Chia-I Wu	ada4605	2010-01-21 15:29:14 +0800	[diff] [blame]	137
				138	<h3>Environment Variables</h3>
				139
				140	<p>There are several environment variables that control the behavior of EGL at
				141	runtime</p>
				142
Andreas Boll	76d4f9e	2012-09-20 16:01:08 +0200	[diff] [blame]	143	<dl>
				144	<dt><code>EGL_DRIVERS_PATH</code></dt>
				145	<dd>
Chia-I Wu	5d8646c	2010-02-02 15:34:55 +0800	[diff] [blame]	146
				147	<p>By default, the main library will look for drivers in the directory where
				148	the drivers are installed to. This variable specifies a list of
				149	colon-separated directories where the main library will look for drivers, in
Chia-I Wu	6fd8b6a	2010-02-02 16:47:53 +0800	[diff] [blame]	150	addition to the default directory. This variable is ignored for setuid/setgid
				151	binaries.</p>
Chia-I Wu	5d8646c	2010-02-02 15:34:55 +0800	[diff] [blame]	152
Chia-I Wu	cba7786	2011-01-04 00:53:19 +0800	[diff] [blame]	153	<p>This variable is usually set to test an uninstalled build. For example, one
				154	may set</p>
				155
				156	<pre>
				157	$ export LD_LIBRARY_PATH=$mesa/lib
				158	$ export EGL_DRIVERS_PATH=$mesa/lib/egl
				159	</pre>
				160
				161	<p>to test a build without installation</p>
				162
Andreas Boll	76d4f9e	2012-09-20 16:01:08 +0200	[diff] [blame]	163	</dd>
Chia-I Wu	5d8646c	2010-02-02 15:34:55 +0800	[diff] [blame]	164
Andreas Boll	76d4f9e	2012-09-20 16:01:08 +0200	[diff] [blame]	165	<dt><code>EGL_DRIVER</code></dt>
				166	<dd>
Chia-I Wu	ada4605	2010-01-21 15:29:14 +0800	[diff] [blame]	167
Chia-I Wu	c98ea26	2011-01-07 16:30:08 +0800	[diff] [blame]	168	<p>This variable specifies a full path to or the name of an EGL driver. It
				169	forces the specified EGL driver to be loaded. It comes in handy when one wants
				170	to test a specific driver. This variable is ignored for setuid/setgid
				171	binaries.</p>
Chia-I Wu	ada4605	2010-01-21 15:29:14 +0800	[diff] [blame]	172
Andreas Boll	76d4f9e	2012-09-20 16:01:08 +0200	[diff] [blame]	173	</dd>
Chia-I Wu	ada4605	2010-01-21 15:29:14 +0800	[diff] [blame]	174
Andreas Boll	76d4f9e	2012-09-20 16:01:08 +0200	[diff] [blame]	175	<dt><code>EGL_PLATFORM</code></dt>
				176	<dd>
Chia-I Wu	ada4605	2010-01-21 15:29:14 +0800	[diff] [blame]	177
Chia-I Wu	b365b15	2010-07-03 17:18:40 +0800	[diff] [blame]	178	<p>This variable specifies the native platform. The valid values are the same
				179	as those for <code>--with-egl-platforms</code>. When the variable is not set,
				180	the main library uses the first platform listed in
Chia-I Wu	3418f74	2010-11-02 23:55:56 +0800	[diff] [blame]	181	<code>--with-egl-platforms</code> as the native platform.</p>
				182
				183	<p>Extensions like <code>EGL_MESA_drm_display</code> define new functions to
				184	create displays for non-native platforms. These extensions are usually used by
				185	applications that support non-native platforms. Setting this variable is
				186	probably required only for some of the demos found in mesa/demo repository.</p>
Chia-I Wu	ada4605	2010-01-21 15:29:14 +0800	[diff] [blame]	187
Andreas Boll	76d4f9e	2012-09-20 16:01:08 +0200	[diff] [blame]	188	</dd>
Chia-I Wu	ada4605	2010-01-21 15:29:14 +0800	[diff] [blame]	189
Andreas Boll	76d4f9e	2012-09-20 16:01:08 +0200	[diff] [blame]	190	<dt><code>EGL_LOG_LEVEL</code></dt>
				191	<dd>
Chia-I Wu	ada4605	2010-01-21 15:29:14 +0800	[diff] [blame]	192
				193	<p>This changes the log level of the main library and the drivers. The valid
				194	values are: <code>debug</code>, <code>info</code>, <code>warning</code>, and
				195	<code>fatal</code>.</p>
				196
Andreas Boll	76d4f9e	2012-09-20 16:01:08 +0200	[diff] [blame]	197	</dd>
Chia-I Wu	ada4605	2010-01-21 15:29:14 +0800	[diff] [blame]	198
Andreas Boll	76d4f9e	2012-09-20 16:01:08 +0200	[diff] [blame]	199	<dt><code>EGL_SOFTWARE</code></dt>
				200	<dd>
Chia-I Wu	ada4605	2010-01-21 15:29:14 +0800	[diff] [blame]	201
				202	<p>For drivers that support both hardware and software rendering, setting this
				203	variable to true forces the use of software rendering.</p>
				204
Andreas Boll	76d4f9e	2012-09-20 16:01:08 +0200	[diff] [blame]	205	</dd>
				206	</dl>
Chia-I Wu	ada4605	2010-01-21 15:29:14 +0800	[diff] [blame]	207
				208	<h2>EGL Drivers</h2>
				209
Andreas Boll	76d4f9e	2012-09-20 16:01:08 +0200	[diff] [blame]	210	<dl>
				211	<dt><code>egl_dri2</code></dt>
				212	<dd>
Chia-I Wu	3418f74	2010-11-02 23:55:56 +0800	[diff] [blame]	213
				214	<p>This driver supports both <code>x11</code> and <code>drm</code> platforms.
Chia-I Wu	65e8f81	2010-12-25 02:45:13 +0800	[diff] [blame]	215	It functions as a DRI driver loader. For <code>x11</code> support, it talks to
				216	the X server directly using (XCB-)DRI2 protocol.</p>
				217
				218	<p>This driver can share DRI drivers with <code>libGL</code>.</p>
Chia-I Wu	3418f74	2010-11-02 23:55:56 +0800	[diff] [blame]	219
Andreas Boll	76d4f9e	2012-09-20 16:01:08 +0200	[diff] [blame]	220	</dd>
Chia-I Wu	3418f74	2010-11-02 23:55:56 +0800	[diff] [blame]	221
Andreas Boll	76d4f9e	2012-09-20 16:01:08 +0200	[diff] [blame]	222	<dt><code>egl_gallium</code></dt>
				223	<dd>
Chia-I Wu	ada4605	2010-01-21 15:29:14 +0800	[diff] [blame]	224
Chia-I Wu	b365b15	2010-07-03 17:18:40 +0800	[diff] [blame]	225	<p>This driver is based on Gallium3D. It supports all rendering APIs and
Nathan Kidd	0691b37	2014-01-03 16:44:00 -0700	[diff] [blame]	226	hardware supported by Gallium3D. It is the only driver that supports OpenVG.
Chia-I Wu	c6320c5	2010-10-28 17:25:07 +0800	[diff] [blame]	227	The supported platforms are X11, DRM, FBDEV, and GDI.</p>
Chia-I Wu	ada4605	2010-01-21 15:29:14 +0800	[diff] [blame]	228
Chia-I Wu	65e8f81	2010-12-25 02:45:13 +0800	[diff] [blame]	229	<p>This driver comes with its own hardware drivers
				230	(<code>pipe_<hw></code>) and client API modules
				231	(<code>st_<api></code>).</p>
				232
Andreas Boll	76d4f9e	2012-09-20 16:01:08 +0200	[diff] [blame]	233	</dd>
Chia-I Wu	ada4605	2010-01-21 15:29:14 +0800	[diff] [blame]	234
Chia-I Wu	65e8f81	2010-12-25 02:45:13 +0800	[diff] [blame]	235	<h2>Packaging</h2>
				236
				237	<p>The ABI between the main library and its drivers are not stable. Nor is
				238	there a plan to stabilize it at the moment. Of the EGL drivers,
				239	<code>egl_gallium</code> has its own hardware drivers and client API modules.
				240	They are considered internal to <code>egl_gallium</code> and there is also no
				241	stable ABI between them. These should be kept in mind when packaging for
				242	distribution.</p>
				243
				244	<p>Generally, <code>egl_dri2</code> is preferred over <code>egl_gallium</code>
				245	when the system already has DRI drivers. As <code>egl_gallium</code> is loaded
				246	before <code>egl_dri2</code> when both are available, <code>egl_gallium</code>
Chia-I Wu	8eea050	2011-06-20 11:14:56 +0900	[diff] [blame]	247	is disabled by default.</p>
Chia-I Wu	65e8f81	2010-12-25 02:45:13 +0800	[diff] [blame]	248
Chia-I Wu	ada4605	2010-01-21 15:29:14 +0800	[diff] [blame]	249	<h2>Developers</h2>
				250
Chia-I Wu	14cbf32	2010-01-27 23:18:22 +0800	[diff] [blame]	251	<p>The sources of the main library and the classic drivers can be found at
Chia-I Wu	3c967a9	2010-01-22 16:31:43 +0800	[diff] [blame]	252	<code>src/egl/</code>. The sources of the <code>egl</code> state tracker can
Chia-I Wu	14cbf32	2010-01-27 23:18:22 +0800	[diff] [blame]	253	be found at <code>src/gallium/state_trackers/egl/</code>.</p>
				254
Chia-I Wu	14cbf32	2010-01-27 23:18:22 +0800	[diff] [blame]	255	<h3>Lifetime of Display Resources</h3>
				256
				257	<p>Contexts and surfaces are examples of display resources. They might live
				258	longer than the display that creates them.</p>
				259
				260	<p>In EGL, when a display is terminated through <code>eglTerminate</code>, all
				261	display resources should be destroyed. Similarly, when a thread is released
Nathan Kidd	0691b37	2014-01-03 16:44:00 -0700	[diff] [blame]	262	through <code>eglReleaseThread</code>, all current display resources should be
				263	released. Another way to destroy or release resources is through functions
Chia-I Wu	14cbf32	2010-01-27 23:18:22 +0800	[diff] [blame]	264	such as <code>eglDestroySurface</code> or <code>eglMakeCurrent</code>.</p>
				265
				266	<p>When a resource that is current to some thread is destroyed, the resource
				267	should not be destroyed immediately. EGL requires the resource to live until
				268	it is no longer current. A driver usually calls
				269	<code>eglIs<Resource>Bound</code> to check if a resource is bound
				270	(current) to any thread in the destroy callbacks. If it is still bound, the
				271	resource is not destroyed.</p>
				272
				273	<p>The main library will mark destroyed current resources as unlinked. In a
				274	driver's <code>MakeCurrent</code> callback,
				275	<code>eglIs<Resource>Linked</code> can then be called to check if a newly
				276	released resource is linked to a display. If it is not, the last reference to
				277	the resource is removed and the driver should destroy the resource. But it
				278	should be careful here because <code>MakeCurrent</code> might be called with an
				279	uninitialized display.</p>
				280
				281	<p>This is the only mechanism provided by the main library to help manage the
				282	resources. The drivers are responsible to the correct behavior as defined by
				283	EGL.</p>
Chia-I Wu	ada4605	2010-01-21 15:29:14 +0800	[diff] [blame]	284
Chia-I Wu	1b2b08c	2010-02-05 12:44:45 +0800	[diff] [blame]	285	<h3><code>EGL_RENDER_BUFFER</code></h3>
				286
				287	<p>In EGL, the color buffer a context should try to render to is decided by the
				288	binding surface. It should try to render to the front buffer if the binding
				289	surface has <code>EGL_RENDER_BUFFER</code> set to
				290	<code>EGL_SINGLE_BUFFER</code>; If the same context is later bound to a
				291	surface with <code>EGL_RENDER_BUFFER</code> set to
				292	<code>EGL_BACK_BUFFER</code>, the context should try to render to the back
				293	buffer. However, the context is allowed to make the final decision as to which
				294	color buffer it wants to or is able to render to.</p>
				295
				296	<p>For pbuffer surfaces, the render buffer is always
				297	<code>EGL_BACK_BUFFER</code>. And for pixmap surfaces, the render buffer is
				298	always <code>EGL_SINGLE_BUFFER</code>. Unlike window surfaces, EGL spec
				299	requires their <code>EGL_RENDER_BUFFER</code> values to be honored. As a
				300	result, a driver should never set <code>EGL_PIXMAP_BIT</code> or
				301	<code>EGL_PBUFFER_BIT</code> bits of a config if the contexts created with the
				302	config won't be able to honor the <code>EGL_RENDER_BUFFER</code> of pixmap or
				303	pbuffer surfaces.</p>
				304
				305	<p>It should also be noted that pixmap and pbuffer surfaces are assumed to be
				306	single-buffered, in that <code>eglSwapBuffers</code> has no effect on them. It
				307	is desirable that a driver allocates a private color buffer for each pbuffer
				308	surface created. If the window system the driver supports has native pbuffers,
				309	or if the native pixmaps have more than one color buffers, the driver should
				310	carefully attach the native color buffers to the EGL surfaces, re-route them if
				311	required.</p>
				312
				313	<p>There is no defined behavior as to, for example, how
				314	<code>glDrawBuffer</code> interacts with <code>EGL_RENDER_BUFFER</code>. Right
				315	now, it is desired that the draw buffer in a client API be fixed for pixmap and
				316	pbuffer surfaces. Therefore, the driver is responsible to guarantee that the
				317	client API renders to the specified render buffer for pixmap and pbuffer
				318	surfaces.</p>
				319
Chia-I Wu	e16f577	2010-02-17 19:52:29 +0800	[diff] [blame]	320	<h3><code>EGLDisplay</code> Mutex</h3>
				321
				322	The <code>EGLDisplay</code> will be locked before calling any of the dispatch
				323	functions (well, except for GetProcAddress which does not take an
				324	<code>EGLDisplay</code>). This guarantees that the same dispatch function will
				325	not be called with the sample display at the same time. If a driver has access
				326	to an <code>EGLDisplay</code> without going through the EGL APIs, the driver
				327	should as well lock the display before using it.
				328
Andreas Boll	b5da52a	2012-09-18 18:57:02 +0200	[diff] [blame]	329	</div>
Chia-I Wu	ada4605	2010-01-21 15:29:14 +0800	[diff] [blame]	330	</body>
				331	</html>