Windows应用支持高分屏

EnableHighDPISupport.cpp

void EnableHighDPISupport() {
  // Enable per-monitor DPI for Win10 or above instead of Win8.1 since Win8.1
  // does not have EnableChildWindowDpiMessage, necessary for correct non-client
  // area scaling across monitors.
  PROCESS_DPI_AWARENESS process_dpi_awareness =
      GetVersion() >= VERSION_WIN10 ? PROCESS_PER_MONITOR_DPI_AWARE
                                    : PROCESS_SYSTEM_DPI_AWARE;
  if (!SetProcessDpiAwarenessWrapper(process_dpi_awareness)) {
    // For windows versions where SetProcessDpiAwareness is not available or
    // failed, try its predecessor.
    ::SetProcessDPIAware();
  }
}

// Method used for Windows 8.1 and later.
// Since we support versions earlier than 8.1, we must dynamically load this
// function from user32.dll, so it won't fail to load in runtime. For earlier
// Windows versions GetProcAddress will return null and report failure so that
// callers can fall back on the deprecated SetProcessDPIAware.
bool SetProcessDpiAwarenessWrapper(PROCESS_DPI_AWARENESS value) {
  decltype(&::SetProcessDpiAwareness) set_process_dpi_awareness_func =
      reinterpret_cast<decltype(&::SetProcessDpiAwareness)>(GetProcAddress(
          GetModuleHandle(L"user32.dll"), "SetProcessDpiAwarenessInternal"));
  if (set_process_dpi_awareness_func) {
    HRESULT hr = set_process_dpi_awareness_func(value);
    if (SUCCEEDED(hr))
      return true;
    DLOG_IF(ERROR, hr == E_ACCESSDENIED)
        << "Access denied error from SetProcessDpiAwareness. Function called "
           "twice, or manifest was used.";
  }
  // TODO(pbos): Consider DCHECKing / NOTREACHED here if the platform version is
  // >= 8.1. That way we can detect future name changes instead of having to
  // discover silent failures.
  return false;
}

// https://chromium.googlesource.com/chromium/src/+/7818e07434df5da87d6cdfe0d30830bf2191097e/chrome/app/chrome_exe_main_win.cc