Function drawNormalLine

QtNodeEditor/src/ConnectionPainter.cpp:169–276

static
void
drawNormalLine(QPainter * painter,
               Connection const & connection)
{
  using QtNodes::ConnectionState;

  ConnectionState const& state =
    connection.connectionState();

  if (state.requiresPort())
    return;

  // colors

  auto const & connectionStyle = connection.style();

  QColor normalColorOut  = connectionStyle.normalColor();
  QColor normalColorIn   = connectionStyle.normalColor();
  QColor selectedColor = connectionStyle.selectedColor();

  bool gradientColor = false;

  if (connectionStyle.useDataDefinedColors())
  {
    using QtNodes::PortType;

    auto dataTypeOut = connection.dataType(PortType::Out);
    auto dataTypeIn = connection.dataType(PortType::In);

    gradientColor = (dataTypeOut.id != dataTypeIn.id);

    normalColorOut  = connectionStyle.normalColor(dataTypeOut.id);
    normalColorIn   = connectionStyle.normalColor(dataTypeIn.id);
    selectedColor = normalColorOut.darker(200);
  }

  // geometry

  ConnectionGeometry const& geom = connection.connectionGeometry();

  double const lineWidth = connectionStyle.lineWidth();

  // draw normal line
  QPen p;

  p.setWidth(lineWidth);

  auto const& graphicsObject = connection.connectionGraphicsObject();
  bool const selected = graphicsObject.isSelected();


  auto cubic = cubicPath(geom);
  if (gradientColor)
  {
    painter->setBrush(Qt::NoBrush);

    QColor c = normalColorOut;