To enable VSync for WIN32 in cocos2d-x, modify initWithRect(...) function in CCGLView.cpp, so it contains this code right before 'initGlew();'

VSyncForCocos2dX.cpp

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#if (CC_TARGET_PLATFORM == CC_PLATFORM_WIN32)
    // Turn on vertical screen sync under Windows.
    // (I.e. it uses the WGL_EXT_swap_control extension)
    typedef BOOL(WINAPI *PFNWGLSWAPINTERVALEXTPROC)(int interval);
    PFNWGLSWAPINTERVALEXTPROC wglSwapIntervalEXT = NULL;
    wglSwapIntervalEXT = (PFNWGLSWAPINTERVALEXTPROC)wglGetProcAddress("wglSwapIntervalEXT");
    if (wglSwapIntervalEXT)
        wglSwapIntervalEXT(1);
#endif

initGlew(); // this already exists int the file
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