boxes.pro Example File
graphicsview/boxes/boxes.pro
  QT += opengl widgets
  requires(qtConfig(combobox))
  qtConfig(opengles.|angle|dynamicgl): error("This example requires Qt to be configured with -opengl desktop")
  HEADERS += 3rdparty/fbm.h \
             glbuffers.h \
             glextensions.h \
             gltrianglemesh.h \
             qtbox.h \
             roundedbox.h \
             scene.h \
             trackball.h
  SOURCES += 3rdparty/fbm.c \
             glbuffers.cpp \
             glextensions.cpp \
             main.cpp \
             qtbox.cpp \
             roundedbox.cpp \
             scene.cpp \
             trackball.cpp
  RESOURCES += boxes.qrc
  # install
  target.path = $$[QT_INSTALL_EXAMPLES]/widgets/graphicsview/boxes
  INSTALLS += target