Fix name of ANGLE libraries and section of default graphics backend on Windows

We had to revert the merge of libEGL and libGLESv2 due to BC issues with
the change, so by default we no longer ship QtANGLE but the other 2
libraries.

Additionally we now mention, that the default/packaged version of Qt will
use dynamic opengl and give -opengl dynamic as an example inside the
configure documentation.

This partly reverts 7853e8e51a65aa5c5d9e4c9bb66549e17a2ff022

Change-Id: Icbf61403cd338809204fc36c6e761b03c3acd829
Reviewed-by: Leena Miettinen <riitta-leena.miettinen@qt.io>
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@qt.io>

3 files changed, 27 insertions, 14 deletions

diff --git a/doc/src/configure.qdoc b/doc/src/configure.qdoc
index 69a53e09..d3fbf87a 100644
--- a/doc/src/configure.qdoc
+++ b/doc/src/configure.qdoc
@@ -248,9 +248,12 @@
     \section1 OpenGL Options for Windows
 
     On Windows, Qt can be configured with the system OpenGL or with \l{ANGLE}.
-    By default, Qt is configured to use ANGLE, which is bundled with Qt and
-    depends on the DirectX SDK. ANGLE enables running Qt applications that
-    depend on OpenGL, without installing the latest OpenGL libraries.
+    By default, Qt is configured to use dynamic OpenGL. This means that it tries
+    to use system OpenGL and falls back to ANGLE, which is bundled with Qt and
+    depends on the DirectX SDK, if native OpenGL does not work. ANGLE enables
+    running Qt applications that depend on OpenGL, without installing the latest
+    OpenGL drivers. If ANGLE also fails, Qt will fall back to software rendering,
+    which is the slowest but most safe of the rendering methods.
 
     The \c -opengl option can be used to configure Qt to use
     the OpenGL in the target system, a different version of OpenGL ES (with or
@@ -258,6 +261,14 @@
     implementations.
 
     \code
+    configure.bat -opengl dynamic
+    \endcode
+
+    With the \c dynamic option, Qt will try to use native OpenGL first. If that
+    fails, it will fall back to ANGLE and finally to software rendering in case
+    of ANGLE failing as well.
+
+    \code
     configure.bat -opengl desktop
     \endcode
 
diff --git a/doc/src/platforms/supported-platforms.qdoc b/doc/src/platforms/supported-platforms.qdoc
index 9fb3ce04..abd5756b 100644
--- a/doc/src/platforms/supported-platforms.qdoc
+++ b/doc/src/platforms/supported-platforms.qdoc
@@ -42,7 +42,7 @@
     Qt is supported on a variety of 32-bit and 64-bit platforms,
     and can usually be built on each platform with GCC, a vendor-supplied
     compiler, or a third party compiler. Open GL (ES) 2.0,
-    DirectX 9 (with ANGLE), or an \l {Qt Quick 2D Renderer} {alternative
+    DirectX 9 or 11 (with ANGLE), or an \l {Qt Quick 2D Renderer} {alternative
     renderer} is required for \l [QtQuick] {Qt Quick} 2.
     \l [QtWidgets] {Qt Widgets}{Widgets} can be used without
     hardware acceleration.
diff --git a/doc/src/platforms/windows.qdoc b/doc/src/platforms/windows.qdoc
index 2113f00a..1823ceac 100644
--- a/doc/src/platforms/windows.qdoc
+++ b/doc/src/platforms/windows.qdoc
@@ -224,9 +224,10 @@
     QtANGLE libraries. Instead, the appropriate library is chosen at
     runtime. By default, Qt will determine whether the system's opengl32.dll
     provides OpenGL 2 functions. If these are present, opengl32.dll is used,
-    otherwise the ANGLE libraries will be used. In case the ANGLE libraries are
-    missing or initialization fails for some reason, an additional fallback is
-    attempted by trying to load \c{opengl32sw.dll}. See below for details.
+    otherwise the ANGLE libraries (libEGL.dll and libGLESv2.dll) will be used.
+    In case the ANGLE libraries are missing or initialization fails for some
+    reason, an additional fallback is attempted by trying to load
+    \c{opengl32sw.dll}. See below for details.
 
     The loading mechanism can be configured through the \c{QT_OPENGL}
     environment variable and the following application attributes:
@@ -243,7 +244,7 @@
 
     The dynamic loading has a significant impact on applications that contain
     native OpenGL calls: they may fail to link since \c qmake no longer
-    automatically adds opengl32.lib or QtANGLE.lib. Instead, applications are
+    automatically adds opengl32.lib or libGLESv2.lib. Instead, applications are
     expected to use the OpenGL functions via the QOpenGLFunctions class. Thus
     the direct dependency on the OpenGL library is removed and all calls will be
     routed during runtime to the implementation chosen by Qt.
@@ -716,11 +717,11 @@
     is a subdirectory named \c {platforms}. \l{Qt Plugins} section has
     additional information about plugins and how Qt searches for them.
 
-    If \l{ANGLE} (the default) is used, you additionally need to include both
-    \c QtANGLE.dll from Qt's 'lib' directory as well as
-    the HLSL compiler from DirectX. The HLSL compiler library,
-    d3dcompiler_XX.dll, where XX is the version number that ANGLE
-    was linked against.
+    If \l{ANGLE} or dynamic OpenGL (the default) is used, you additionally
+    need to include both \c libEGL.dll and \c libGLESv2.dll from Qt's \c lib
+    directory as well as the HLSL compiler from DirectX. The HLSL compiler
+    library, d3dcompiler_XX.dll, where XX is the version number that ANGLE
+    (libGLESv2) was linked against.
 
     If Qt was configured to link against ICU or OpenSSL, the respective DLL's
     need to be added to the \c release folder, too.
@@ -822,7 +823,8 @@
     \header
         \li{2,1} File Name
     \row
-        \li QtANGLE.dll
+        \li libEGL.dll
+        \li libGLESv2.dll
         \li d3dcompiler_XX.dll
     \endtable