gstreamer/ext/qt
Milian Wolff 3e0d557744 qmlgl: ensure Qt defines GLsync to fix compile on some platforms
By explictly including QtGui/qopengl.h we force the code path that
defines GLsync in the Qt-specific way. Without that, some platforms
failed to compile the qmlgl plugin, since neither Qt nor gstreamer
defined GLsync then, leading to e.g.:

```
make[4]: Entering directory '/.../gst-plugins-good-1.16.1/ext/qt'
  CXX      libgstqmlgl_la-qtitem.lo
In file included from gstqtgl.h:32,
                 from qtitem.h:27,
                 from qtitem.cc:28:
/.../usr/include/gstreamer-1.0/
gst/gl/gstglfuncs.h:93:17: error: expected identifier before ‘*’ token
   ret (GSTGLAPI *name) args;
                 ^
/.../usr/include/gstreamer-1.0/
gst/gl/glprototypes/sync.h:27:1: note: in expansion of macro
‘GST_GL_EXT_FUNCTION’
 GST_GL_EXT_FUNCTION (GLsync, FenceSync,
 ^~~~~~~~~~~~~~~~~~~
```
2020-03-05 03:21:48 +00:00
..
gstplugin.cc
gstqsgtexture.cc
gstqsgtexture.h
gstqtgl.h
gstqtglutility.cc
gstqtglutility.h
gstqtsink.cc
gstqtsink.h
gstqtsrc.cc
gstqtsrc.h
meson.build
qtitem.cc
qtitem.h
qtplugin.pro
qtwindow.cc
qtwindow.h
README.md

Building for non-linux platforms

Compiling the gstqmlgl plugin for non-linux platforms is not so trivial. This file explains the steps that need to be followed for a successful build.

Step 1

Build GStreamer for the target platform using cerbero.

Step 2

Enter the cerbero shell:

./cerbero-uninstalled -c config/<target platform config>.cbc shell

Step 3

Export the following environment variables:

export PATH=/path/to/Qt/<version>/<platform>/bin:$PATH

if you are cross-compiling (ex. for android), also export:

export PKG_CONFIG_SYSROOT_DIR=/

Additionally, if you are building for android:

export ANDROID_NDK_ROOT=$ANDROID_NDK

Note: the ANDROID_NDK variable is set by the cerbero shell; if you are not using this shell, set it to the directory where you have installed the android NDK. Additionally, if you are not building through the cerbero shell, it is also important to have set PKG_CONFIG_LIBDIR to $GSTREAMER_ROOT/lib/pkgconfig.

Step 4

cd to the directory of the gstqmlgl plugin and run:

qmake .
make

Step 5

Copy the built plugin to your $GSTREAMER_ROOT/lib/gstreamer-1.0 or link to it directly if it is compiled statically