docs/egl: Update egl.html.
Various updates and a new section about packaging.
diff --git a/docs/egl.html b/docs/egl.html
index ee9bf35..ff610c3 100644
--- a/docs/egl.html
+++ b/docs/egl.html
@@ -19,10 +19,7 @@
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>
@@ -86,16 +83,19 @@
<li><code>--enable-gles1</code> and <code>--enable-gles2</code>
-<p>These options enable OpenGL ES support in OpenGL. The result is
-one big library that supports multiple APIs.</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-gles-overlay</code>
-<p>This option enables OpenGL ES as separate libraries. This is an alternative
-approach to enable OpenGL ES. It is only supported by
-<code>egl_gallium</code>.</p>
+<p>This option enables OpenGL ES as separate internal libraries. This is an
+alternative approach to enable OpenGL ES.</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>
@@ -180,8 +180,10 @@
<li><code>egl_dri2</code>
<p>This driver supports both <code>x11</code> and <code>drm</code> platforms.
-It functions as a DRI2 driver loader. For <code>x11</code> support, it talks
-to the X server directly using (XCB-)DRI2 protocol.</p>
+It functions as a DRI driver loader. For <code>x11</code> support, it talks to
+the X server directly using (XCB-)DRI2 protocol.</p>
+
+<p>This driver can share DRI drivers with <code>libGL</code>.</p>
</li>
@@ -191,6 +193,10 @@
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>
<li><code>egl_glx</code>
@@ -202,6 +208,21 @@
</li>
</ul>
+<h2>Packaging</h2>
+
+<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>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>
<p>The sources of the main library and the classic drivers can be found at