ConnectionGraphicsObject &cgo,

BasicGraphicsScene &scene)

: _ngo(ngo)

, _cgo(cgo)

, _scene(scene)

{

// 1. Connection requires a port.

PortType requiredPort = _cgo.connectionState().requiredPort();

if (requiredPort == PortType::None) {

return false;

}

NodeId connectedNodeId = getNodeId(oppositePort(requiredPort), _cgo.connectionId());

// 2. Forbid connecting the node to itself.

if (_ngo.nodeId() == connectedNodeId)

return false;

// 3. Connection loose end is above the node port.

QPointF connectionPoint = _cgo.sceneTransform().map(_cgo.endPoint(requiredPort));

*portIndex = nodePortIndexUnderScenePoint(requiredPort, connectionPoint);

if (*portIndex == InvalidPortIndex) {

return false;

}

// 4. Model allows connection.

AbstractGraphModel &model = _ngo.nodeScene()->graphModel();

ConnectionId connectionId = makeCompleteConnectionId(_cgo.connectionId(), // incomplete

_ngo.nodeId(), // missing node id

*portIndex); // missing port index

return model.connectionPossible(connectionId);

{

// 1. Check conditions from 'canConnect'.

PortIndex targetPortIndex = InvalidPortIndex;

if (!canConnect(&targetPortIndex)) {

return false;

}

// 2. Create new connection.

ConnectionId incompleteConnectionId = _cgo.connectionId();

ConnectionId newConnectionId = makeCompleteConnectionId(incompleteConnectionId,

_ngo.nodeId(),

targetPortIndex);

_ngo.nodeScene()->resetDraftConnection(true);

_ngo.nodeScene()->undoStack().push(new ConnectCommand(_ngo.nodeScene(), newConnectionId));

return true;

{

ConnectionId connectionId = _cgo.connectionId();

_scene.undoStack().push(new DisconnectCommand(&_scene, connectionId));

AbstractNodeGeometry &geometry = _scene.nodeGeometry();

QPointF scenePos = geometry.portScenePosition(_ngo.nodeId(),

portToDisconnect,

getPortIndex(portToDisconnect, connectionId),

_ngo.sceneTransform());

// Converted to "draft" connection with the new incomplete id.

ConnectionId incompleteConnectionId = makeIncompleteConnectionId(connectionId, portToDisconnect);

// Grabs the mouse

auto const &draftConnection = _scene.makeDraftConnection(incompleteConnectionId);

QPointF const looseEndPos = draftConnection->mapFromScene(scenePos);

draftConnection->setEndPoint(portToDisconnect, looseEndPos);

// Repaint connection points.

NodeId connectedNodeId = getNodeId(oppositePort(portToDisconnect), connectionId);

_scene.nodeGraphicsObject(connectedNodeId)->update();

NodeId disconnectedNodeId = getNodeId(portToDisconnect, connectionId);

_scene.nodeGraphicsObject(disconnectedNodeId)->update();

return true;

{

auto const &state = _cgo.connectionState();

return state.requiredPort();

PortIndex portIndex) const

{

AbstractNodeGeometry &geometry = _scene.nodeGeometry();

QPointF p = geometry.portScenePosition(_ngo.nodeId(),

portType,

portIndex,

_ngo.sceneTransform());

return p;

QPointF const &scenePoint) const

{

AbstractNodeGeometry &geometry = _scene.nodeGeometry();

QTransform sceneTransform = _ngo.sceneTransform();

QPointF nodePoint = sceneTransform.inverted().map(scenePoint);

return geometry.checkPortHit(_ngo.nodeId(), portType, nodePoint);