Add glew dependency for newer Qt6 version

CMakeLists.txt

@@ -22,6 +22,8 @@ if(NOT TARGET OpenGL::GL OR NOT TARGET OpenGL::GLU)
     find_package(OpenGL REQUIRED)
 endif()
 
+find_package(GLEW REQUIRED)
+
 set(MOC_HEADER_FILES
     QGLViewer/camera.h
     QGLViewer/frame.h
@@ -109,6 +111,7 @@ else()
     target_link_libraries(${PROJECT_NAME} PUBLIC ${OPENGL_LIBRARIES})
     target_include_directories(${PROJECT_NAME} SYSTEM PUBLIC ${OPENGL_INCLUDE_DIR})
 endif()
+    target_link_libraries(${PROJECT_NAME} PUBLIC GLEW::GLEW)
 
 target_include_directories(${PROJECT_NAME} PRIVATE ${CMAKE_CURRENT_BINARY_DIR})
 target_include_directories(${PROJECT_NAME} SYSTEM PUBLIC "$<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}>")

QGLViewer/VRender/Primitive.h

@@ -11,6 +11,7 @@
 # include <windows.h>
 #endif
 
+# include <GL/glew.h>
 #ifdef __APPLE__
 # include <OpenGL/gl.h>
 #else

QGLViewer/VRender/Types.h

@@ -5,6 +5,7 @@
 # include <windows.h>
 #endif
 
+# include <GL/glew.h>
 #ifdef __APPLE__
 # include <OpenGL/gl.h>
 #else

QGLViewer/VRender/VRender.cpp

@@ -2,6 +2,7 @@
 # include <windows.h>
 #endif
 
+# include <GL/glew.h>
 #ifdef __APPLE__
 # include <OpenGL/gl.h>
 #else

QGLViewer/config.h

@@ -55,6 +55,7 @@ Error : libQGLViewer requires a minimum Qt version of 5.4 Error
 
 // OpenGL includes - Included here and hence shared by all the files that need
 // OpenGL headers.
+#include <GL/glew.h>
 #include <QOpenGLWidget>
 
 // GLU was removed from Qt in version 4.8