dynamically loaded by the main library and most of the EGL API calls are
directly dispatched to the drivers.</p>
-<p>The driver in use decides the window system to support. For drivers that
-support hardware rendering, there are usually multiple drivers supporting the
-same window system. Each one of of them supports a certain range of graphics
-cards.</p>
+<p>The driver in use decides the window system to support.</p>
<h2>Build EGL</h2>
<ol>
<li>
-<p>Run <code>configure</code> with the desired state trackers and enable
-the Gallium driver for your hardware. For example</p>
+<p>Run <code>configure</code> with the desired client APIs and enable
+the driver for your hardware. For example</p>
<pre>
- $ ./configure --with-state-trackers=egl,es,vega --enable-gallium-{swrast,intel}
+ $ ./configure --enable-gles2 --enable-openvg --enable-gallium-nouveau
</pre>
-<p>The main library will be enabled by default. The <code>egl</code> state
-tracker is needed by a number of EGL drivers. EGL drivers will be covered
-later. The <a href="opengles.html">es state tracker</a> provides OpenGL ES 1.x
-and 2.x and the <a href="openvg.html">vega state tracker</a> provides OpenVG
-1.x.</p>
+<p>The main library and OpenGL is enabled by default. The first option above
+enables <a href="opengles.html">OpenGL ES 2.x</a>. The second option enables
+<a href="openvg.html">OpenVG</a>.</p>
+
</li>
<li>Build and install Mesa as usual.</li>
</ol>
<p>In the given example, it will build and install <code>libEGL</code>,
-<code>libGLESv1_CM</code>, <code>libGLESv2</code>, <code>libOpenVG</code>, and
-one or more EGL drivers.</p>
+<code>libGL</code>, <code>libGLESv1_CM</code>, <code>libGLESv2</code>,
+<code>libOpenVG</code>, and one or more EGL drivers.</p>
<h3>Configure Options</h3>
</li>
-<li><code>--with-egl-displays</code>
+<li><code>--with-egl-platforms</code>
+
+<p>List the platforms (window systems) to support. Its argument is a comma
+seprated string such as <code>--with-egl-platforms=x11,drm</code>. It decides
+the platforms a driver may support. The first listed platform is also used by
+the main library to decide the native platform: the platform the EGL native
+types such as <code>EGLNativeDisplayType</code> or
+<code>EGLNativeWindowType</code> defined for.</p>
-<p>List the window system(s) to support. It is by default <code>x11</code>,
-which supports the X Window System. Its argument is a comma separated string
-like, for example, <code>--with-egl-displays=x11,kms</code>. Because an EGL
-driver decides which window system to support, this example will enable two
-(sets of) EGL drivers. One supports the X window system and the other supports
-bare KMS (kernel modesetting).</p>
+<p>The available platforms are <code>x11</code>, <code>drm</code>,
+<code>fbdev</code>, and <code>gdi</code>. The <code>gdi</code> platform can
+only be built with SCons. Unless for special needs, the build system should
+select the right platforms automatically.</p>
</li>
-<li><code>--with-state-trackers</code>
+<li><code>--enable-gles1</code> and <code>--enable-gles2</code>
-<p>The argument is a comma separated string. It is usually used to specify the
-rendering APIs, like OpenGL ES or OpenVG, to build. But it should be noted
-that a number of EGL drivers depend on the <code>egl</code> state tracker.
-They will <em>not</em> be built without the <code>egl</code> state tracker.</p>
+<p>These options enable OpenGL ES support in OpenGL. The result is one big
+internal library that supports multiple APIs.</p>
</li>
-<li><code>--enable-gallium-swrast</code>
+<li><code>--enable-gles-overlay</code>
+
+<p>This option enables OpenGL ES as separate internal libraries. This is an
+alternative approach to enable OpenGL ES.</p>
-<p>This option is not specific to EGL. But if there is no driver for your
-hardware, or you are experiencing problems with the hardware driver, you can
-enable the swrast DRM driver. It is a dummy driver and EGL will fallback to
-software rendering automatically.</p>
+<p>This is only supported by <code>egl_gallium</code>. For systems using DRI
+drivers, <code>--enable-gles1</code> and <code>--enable-gles2</code> are
+suggested instead as all drivers will benefit.</p>
</li>
-</ul>
-<h3>OpenGL</h3>
+<li><code>--enable-openvg</code>
+
+<p>OpenVG must be explicitly enabled by this option.</p>
-<p>The OpenGL state tracker is not built in the above example. It should be
-noted that the classic <code>libGL</code> is not a state tracker and cannot be
-used with EGL (unless the EGL driver in use is <code>egl_glx</code>). To build
-the OpenGL state tracker, one may append <code>glx</code> to
-<code>--with-state-trackers</code> and manually build
-<code>src/gallium/winsys/xlib/</code>.</p>
+</li>
+
+<li><code>--enable-gallium-egl</code>
+
+<p>Explicitly enable or disable <code>egl_gallium</code>.</p>
+
+</li>
+
+</ul>
<h2>Use EGL</h2>
-<p> The demos for OpenGL ES and OpenVG can be found in <code>progs/es1/</code>,
-<code>progs/es2/</code> and <code>progs/openvg/</code>. You can use them to
-test your build. For example,</p>
+<h3>Demos</h3>
-<pre>
- $ cd progs/es1/xegl
- $ make
- $ ./torus
-</pre>
+<p>There are demos for the client APIs supported by EGL. They can be found in
+mesa/demos repository.</p>
<h3>Environment Variables</h3>
addition to the default directory. This variable is ignored for setuid/setgid
binaries.</p>
+<p>This variable is usually set to test an uninstalled build. For example, one
+may set</p>
+
+<pre>
+ $ export LD_LIBRARY_PATH=$mesa/lib
+ $ export EGL_DRIVERS_PATH=$mesa/lib/egl
+</pre>
+
+<p>to test a build without installation</p>
+
</li>
<li><code>EGL_DRIVER</code>
</li>
-<li><code>EGL_DISPLAY</code>
+<li><code>EGL_PLATFORM</code>
-<p>When <code>EGL_DRIVER</code> is not set, the main library loads <em>all</em>
-EGL drivers that support a certain window system. <code>EGL_DISPLAY</code> can
-be used to specify the window system and the valid values are, for example,
-<code>x11</code> or <code>kms</code>. When the variable is not set, the main
-library defaults the value to the first window system listed in
-<code>--with-egl-displays</code> at configuration time.
+<p>This variable specifies the native platform. The valid values are the same
+as those for <code>--with-egl-platforms</code>. When the variable is not set,
+the main library uses the first platform listed in
+<code>--with-egl-platforms</code> as the native platform.</p>
+
+<p>Extensions like <code>EGL_MESA_drm_display</code> define new functions to
+create displays for non-native platforms. These extensions are usually used by
+applications that support non-native platforms. Setting this variable is
+probably required only for some of the demos found in mesa/demo repository.</p>
</li>
<h2>EGL Drivers</h2>
-<p>There are two categories of EGL drivers: Gallium and classic.</p>
+<ul>
+<li><code>egl_dri2</code>
-<p>Gallium EGL drivers supports all rendering APIs specified in EGL 1.4. The
-support for optional EGL functions and EGL extensions is usually more complete
-than the classic ones. These drivers depend on the <code>egl</code> state
-tracker to build. The available drivers are</p>
+<p>This driver supports both <code>x11</code> and <code>drm</code> platforms.
+It functions as a DRI driver loader. For <code>x11</code> support, it talks to
+the X server directly using (XCB-)DRI2 protocol.</p>
-<ul>
-<li><code>egl_<dpy>_i915</code></li>
-<li><code>egl_<dpy>_i965</code></li>
-<li><code>egl_<dpy>_radeon</code></li>
-<li><code>egl_<dpy>_nouveau</code></li>
-<li><code>egl_<dpy>_swrast</code></li>
-<li><code>egl_<dpy>_vmwgfx</code></li>
-</ul>
+<p>This driver can share DRI drivers with <code>libGL</code>.</p>
-<p><code><dpy></code> is given by <code>--with-egl-displays</code> at
-configuration time. There will be one EGL driver for each combination of the
-displays listed and the hardware drivers enabled.</p>
+</li>
-<p>Classic EGL drivers, on the other hand, supports only OpenGL as its
-rendering API. They can be found under <code>src/egl/drivers/</code>. There
-are 3 of them</p>
+<li><code>egl_gallium</code>
+
+<p>This driver is based on Gallium3D. It supports all rendering APIs and
+hardwares supported by Gallium3D. It is the only driver that supports OpenVG.
+The supported platforms are X11, DRM, FBDEV, and GDI.</p>
+
+<p>This driver comes with its own hardware drivers
+(<code>pipe_<hw></code>) and client API modules
+(<code>st_<api></code>).</p>
+
+</li>
-<ul>
<li><code>egl_glx</code>
<p>This driver provides a wrapper to GLX. It uses exclusively GLX to implement
It is accelerated when the GLX is. As such, it cannot provide functions that
is not available in GLX or GLX extensions.</p>
</li>
+</ul>
-<li><code>egl_dri2</code>
-
-<p>This driver supports the X Window System as its window system. It functions
-as a DRI2 driver loader. Unlike <code>egl_glx</code>, it has no dependency on
-<code>libGL</code>. It talks to the X server directly using DRI2 protocol.</p>
-
-</li>
-<li><code>egl_dri</code>
-
-<p>This driver lacks maintenance and does <em>not</em> build. It is similiar
-to <code>egl_dri2</code> in that it functions as a DRI(1) driver loader. But
-unlike <code>egl_dri2</code>, it supports Linux framebuffer devices as its
-window system and supports EGL_MESA_screen_surface extension. As DRI1 drivers
-are phasing out, it might eventually be replaced by <code>egl_dri2</code>.</p>
+<h2>Packaging</h2>
-</li>
-</ul>
+<p>The ABI between the main library and its drivers are not stable. Nor is
+there a plan to stabilize it at the moment. Of the EGL drivers,
+<code>egl_gallium</code> has its own hardware drivers and client API modules.
+They are considered internal to <code>egl_gallium</code> and there is also no
+stable ABI between them. These should be kept in mind when packaging for
+distribution.</p>
-<p>To use the classic drivers, one must manually set <code>EGL_DRIVER</code> at
-runtime.</p>
+<p>Generally, <code>egl_dri2</code> is preferred over <code>egl_gallium</code>
+when the system already has DRI drivers. As <code>egl_gallium</code> is loaded
+before <code>egl_dri2</code> when both are available, <code>egl_gallium</code>
+may either be disabled with <code>--disable-gallium-egl</code> or packaged
+separately.</p>
<h2>Developers</h2>
<ul>
<li>Pass the conformance tests</li>
-<li>Better automatic driver selection: <code>EGL_DISPLAY</code> loads all
-drivers and might eat too much memory.</li>
+<li>Mixed use of OpenGL, OpenGL ES 1.1, and OpenGL ES 2.0 is supported. But
+which one of <code>libGL.so</code>, <code>libGLESv1_CM.so</code>, and
+<code>libGLESv2.so</code> should an application link to? Bad things may happen
+when, say, an application is linked to <code>libGLESv2.so</code> and
+<code>libcairo</code>, which is linked to <code>libGL.so</code> instead.</li>
</ul>
projects / mesa.git / blobdiff