Method MouseMoveEvent

Charts/Core/vtkChartParallelCoordinates.cxx:556–647

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//------------------------------------------------------------------------------
bool vtkChartParallelCoordinates::MouseMoveEvent(const vtkContextMouseEvent& mouse)
{
  if (mouse.GetButton() == this->Actions.Select())
  {
    // If an axis is selected, then lets try to narrow down a selection...
    if (this->Storage->CurrentAxis >= 0)
    {
      std::array<float, 2>& range = this->Storage->CurrentSelection;

      // Normalize the coordinates
      float current = mouse.GetScenePos().GetY();
      current -= this->Storage->Transform->GetMatrix()->GetElement(1, 2);
      current /= this->Storage->Transform->GetMatrix()->GetElement(1, 1);

      if (current > 1.0f)
      {
        range[1] = 1.0f;
      }
      else if (current < 0.0f)
      {
        range[1] = 0.0f;
      }
      else
      {
        range[1] = current;
      }
    }
    this->Scene->SetDirty(true);
  }
  else if (mouse.GetButton() == this->Actions.Pan())
  {
    if (this->Storage->CurrentAxis < 0) // can be -1
      return false;
    vtkAxis* axis = this->Storage->Axes[this->Storage->CurrentAxis];
    if (this->Storage->AxisResize == 0)
    {
      // Move the axis in x
      float deltaX = mouse.GetScenePos().GetX() - mouse.GetLastScenePos().GetX();

      axis->SetPoint1(axis->GetPoint1()[0] + deltaX, axis->GetPoint1()[1]);
      axis->SetPoint2(axis->GetPoint2()[0] + deltaX, axis->GetPoint2()[1]);

      vtkAxis* leftAxis = this->Storage->CurrentAxis > 0
        ? this->Storage->Axes[this->Storage->CurrentAxis - 1]
        : nullptr;

      vtkAxis* rightAxis =
        this->Storage->CurrentAxis < static_cast<int>(this->Storage->Axes.size()) - 1
        ? this->Storage->Axes[this->Storage->CurrentAxis + 1]
        : nullptr;

      if (leftAxis && axis->GetPoint1()[0] < leftAxis->GetPoint1()[0])
      {
        this->SwapAxes(this->Storage->CurrentAxis, this->Storage->CurrentAxis - 1);
        this->Storage->CurrentAxis--;
      }
      else if (rightAxis && axis->GetPoint1()[0] > rightAxis->GetPoint1()[0])
      {