Method SetFollowAndRotate

libs/drape_frontend/user_event_stream.cpp:615–684

}

bool UserEventStream::SetFollowAndRotate(m2::PointD const & userPos, m2::PointD const & pixelPos, double azimuth,
                                         int preferredZoomLevel, double autoScale, bool isAnim, bool isAutoScale,
                                         Animation::TAction const & onFinishAction,
                                         TAnimationCreator const & parallelAnimCreator)
{
  // Reset current follow-and-rotate animation if possible.
  if (isAnim && !InterruptFollowAnimations(false /* force */))
    return false;

  ScreenBase const & currentScreen = GetCurrentScreen();
  ScreenBase screen = currentScreen;

  if (preferredZoomLevel == kDoNotChangeZoom && !isAutoScale)
  {
    GetTargetScreen(screen);
    screen.SetAngle(-azimuth);
  }
  else
  {
    screen.SetFromParams(userPos, -azimuth, isAutoScale ? autoScale : GetScreenScale(preferredZoomLevel));
  }
  screen.MatchGandP3d(userPos, pixelPos);

  ShrinkAndScaleInto(screen, df::GetWorldRect());

  if (isAnim)
  {
    drape_ptr<Animation> anim;
    double const moveDuration =
        PositionInterpolator::GetMoveDuration(currentScreen.GetOrg(), screen.GetOrg(), currentScreen.PixelRectIn3d(),
                                              (currentScreen.GetScale() + screen.GetScale()) / 2.0);
    if (moveDuration > kMaxAnimationTimeSec)
    {
      // Run pretty move animation if we are far from userPos.
      anim = GetPrettyFollowAnimation(currentScreen, userPos, screen.GetScale(), -azimuth, pixelPos);
    }
    else
    {
      // Run follow-and-rotate animation.
      anim = GetFollowAnimation(currentScreen, userPos, screen.GetScale(), -azimuth, pixelPos, isAutoScale);
    }

    if (preferredZoomLevel != kDoNotChangeZoom)
    {
      anim->SetCouldBeInterrupted(false);
      anim->SetCouldBeBlended(false);
    }

    anim->SetOnFinishAction(onFinishAction);

    if (parallelAnimCreator != nullptr)
    {
      drape_ptr<ParallelAnimation> parallelAnim = make_unique_dp<ParallelAnimation>();
      parallelAnim->SetCustomType(kParallelFollowAnim);
      parallelAnim->AddAnimation(
          parallelAnimCreator(anim->GetType() == Animation::Type::MapFollow ? make_ref(anim) : nullptr));
      parallelAnim->AddAnimation(std::move(anim));
      m_animationSystem.CombineAnimation(std::move(parallelAnim));