example 'camera': fix orientation of both video and saved images

examples/camera/cpp/qt.cpp

@@ -0,0 +1,33 @@
+#include "qt.h"
+#include <QImage>
+#include <QtDebug>
+
+#ifdef PLUGIN
+  #include <ecl_fun_plugin.h>
+#else
+  #include <ecl_fun.h>
+#endif
+
+QT_BEGIN_NAMESPACE
+
+QObject* ini() {
+  static QObject* qt = nullptr;
+  if (qt == nullptr) {
+    qt = new QT;
+#ifdef PLUGIN
+    ini_lisp();
+#endif
+  }
+  return qt;
+}
+
+QVariant QT::rotateImage(const QVariant& imagePath, const QVariant& angle) {
+  // rotates image, replacing it; must be called from the UI thread, see QRUN*
+  QString path(imagePath.toString());
+  QImage img(path);
+  QImage rotated = img.transformed(QTransform().rotate(angle.toReal()));
+  rotated.save(path);
+  return imagePath;
+}
+
+QT_END_NAMESPACE

examples/camera/cpp/qt.h

@@ -0,0 +1,22 @@
+#pragma once
+
+#include <QtCore>
+
+#ifdef Q_CC_MSVC
+#define LIB_EXPORT __declspec(dllexport)
+#else
+#define LIB_EXPORT
+#endif
+
+QT_BEGIN_NAMESPACE
+
+extern "C" { LIB_EXPORT QObject* ini(); }
+
+class QT : public QObject {
+  Q_OBJECT
+
+public:
+  Q_INVOKABLE QVariant rotateImage(const QVariant&, const QVariant&);
+};
+
+QT_END_NAMESPACE

examples/camera/cpp/qt.pro

@@ -0,0 +1,27 @@
+QT          += gui
+TEMPLATE    = lib
+CONFIG      += c++17 plugin release no_keywords
+DEFINES     += PLUGIN
+INCLUDEPATH = /usr/local/include ../../../src/cpp
+LIBS        = -L/usr/local/lib -lecl
+DESTDIR     = ./
+TARGET      = qt
+OBJECTS_DIR = ./tmp/
+MOC_DIR     = ./tmp/
+
+HEADERS += qt.h
+SOURCES += qt.cpp
+
+linux {
+  LIBS += -L../../../platforms/linux/lib
+}
+
+macx {
+  LIBS += -L../../../platforms/macos/lib
+}
+
+win32 {
+  include(../../../src/windows.pri)
+
+  LIBS += -L../../../platforms/windows/lib
+}