Add Crow's Foot notation for relationship drawing, disabled by default

2 files changed, 118 insertions, 32 deletions

diff --git a/src/items/database/databaserelationship.cpp b/src/items/database/databaserelationship.cpp
index 8b4ceda..d908409 100644
--- a/src/items/database/databaserelationship.cpp
+++ b/src/items/database/databaserelationship.cpp
@@ -29,13 +29,73 @@ public:
 		cardinality(ZeroOrMore),
 		onUpdateAction(NoAction),
 		onDeleteAction(NoAction)
-		{}
+	{
+		if (!pathsInitialized) {
+			pathsInitialized = true;
+
+			paths[1].moveTo(-4.5, 0);
+			paths[1].lineTo(0, 8);
+			paths[1].lineTo(4.5, 0);
+			paths[1].moveTo(-4, 10);
+			paths[1].lineTo(4, 10);
+
+			paths[3].moveTo(-4, 5);
+			paths[3].lineTo(4, 5);
+			paths[3].moveTo(-4, 8);
+			paths[3].lineTo(4, 8);
+
+			paths[2].moveTo(-4, 5);
+			paths[2].lineTo(4, 5);
+			paths[2].addEllipse(-3.5, 8, 7, 7);
+
+			paths[0].moveTo(-4.5, 0);
+			paths[0].lineTo(0, 8);
+			paths[0].lineTo(4.5, 0);
+			paths[0].addEllipse(-3.5, 8, 7, 7);
+
+			paths[4].moveTo(-4.5, 10);
+			paths[4].lineTo(0, 0);
+			paths[4].lineTo(4.5, 10);
+		}
+	}
 
 	Cardinality cardinality;
 	Action onUpdateAction;
 	Action onDeleteAction;
+
+	bool fillEnds;
+	QPainterPath sourceEnd;
+	QPainterPath targetEnd;
+	QPolygonF line;
+
+	QPainterPath crowsFootPath(Cardinality cardinality)
+	{
+		switch (cardinality) {
+			case ZeroOrMore:
+				return paths[0];
+			case OneOrMore:
+				return paths[1];
+			case ZeroOrOne:
+				return paths[2];
+			case One:
+				return paths[3];
+		}
+		Q_ASSERT(false);
+		return QPainterPath();
+	}
+
+	QPainterPath arrowHeadPath()
+	{
+		return paths[4];
+	}
+
+	static bool pathsInitialized;
+	static QPainterPath paths[5];
 };
 
+bool DatabaseRelationship::PrivateData::pathsInitialized = false;
+QPainterPath DatabaseRelationship::PrivateData::paths[5];
+
 DatabaseRelationship::DatabaseRelationship(DiagramItem *parent)
 	: DiagramConnection(parent), d(new PrivateData)
 {
@@ -60,9 +120,17 @@ DatabaseRelationship::setCardinality(Cardinality cardinality)
 	if (d->cardinality != cardinality) {
 		d->cardinality = cardinality;
 		emit propertyChanged("cardinality", cardinality);
+		updateLayout();
+		update();
 	}
 }
 
+bool
+DatabaseRelationship::isRequired() const
+{
+	return true; // FIXME
+}
+
 QRectF
 DatabaseRelationship::boundingRect() const
 {
@@ -73,17 +141,18 @@ QPainterPath
 DatabaseRelationship::shape() const
 {
 	QPainterPath path;
-	if (m_line.isEmpty())
+	if (d->line.isEmpty())
 		return path;
-	path.moveTo(m_line[0]);
-	for (int i = 1; i < m_line.size(); i++)
-		path.lineTo(m_line[i]);
-	path.addPolygon(m_arrowHead);
+	path.moveTo(d->line[0]);
+	for (int i = 1; i < d->line.size(); i++)
+		path.lineTo(d->line[i]);
+	path.addPath(d->targetEnd);
+	path.addPath(d->sourceEnd);
 	QPen pen(QPen(QColor(0, 0, 0), 1));
 	pen.setJoinStyle(Qt::MiterJoin);
 	QPainterPathStroker ps;
 	ps.setCapStyle(pen.capStyle());
-	ps.setWidth(pen.widthF() + 0.3);
+	ps.setWidth(pen.widthF() + 2);
 	ps.setJoinStyle(pen.joinStyle());
 	ps.setMiterLimit(pen.miterLimit());
 	return ps.createStroke(path);
@@ -104,9 +173,11 @@ DatabaseRelationship::paint(QPainter *painter, const QStyleOptionGraphicsItem *o
 	}
 
 	painter->setPen(pen);
-	painter->drawPolyline(m_line);
-	painter->setBrush(pen.color());
-	painter->drawPolygon(m_arrowHead);
+	painter->drawPolyline(d->line);
+	if (d->fillEnds)
+		painter->setBrush(pen.color());
+	painter->drawPath(d->sourceEnd);
+	painter->drawPath(d->targetEnd);
 }
 
 QVariant
@@ -156,10 +227,10 @@ DatabaseRelationship::updateLayout()
 		if (!verticalIntersection.isNull() && horizontalIntersection.isNull()) {
 			qreal y = verticalIntersection.min() + verticalIntersection.length() / 2;
 			if (rect1.right() < rect2.left()) {
-				m_line = QPolygonF() << QPointF(rect1.right(), y) << QPointF(rect2.left(), y);
+				d->line = QPolygonF() << QPointF(rect1.right(), y) << QPointF(rect2.left(), y);
 			}
 			else {
-				m_line = QPolygonF() << QPointF(rect1.left(), y) << QPointF(rect2.right(), y);
+				d->line = QPolygonF() << QPointF(rect1.left(), y) << QPointF(rect2.right(), y);
 			}
 			haveLine = true;
 		}
@@ -170,10 +241,10 @@ DatabaseRelationship::updateLayout()
 		if (verticalIntersection.isNull() && !horizontalIntersection.isNull()) {
 			qreal x = horizontalIntersection.min() + horizontalIntersection.length() / 2;
 			if (rect1.bottom() < rect2.top()) {
-				m_line = QPolygonF() << QPointF(x, rect1.bottom()) << QPointF(x, rect2.top());
+				d->line = QPolygonF() << QPointF(x, rect1.bottom()) << QPointF(x, rect2.top());
 			}
 			else {
-				m_line = QPolygonF() << QPointF(x, rect1.top()) << QPointF(x, rect2.bottom());
+				d->line = QPolygonF() << QPointF(x, rect1.top()) << QPointF(x, rect2.bottom());
 			}
 			haveLine = true;
 		}
@@ -217,7 +288,7 @@ DatabaseRelationship::updateLayout()
 			}
 		}
 
-		m_line = QPolygonF()
+		d->line = QPolygonF()
 			<< QPointF(x1, y1)
 			<< QPointF(x2, y2)
 			<< QPointF(x3, y3);
@@ -252,23 +323,41 @@ DatabaseRelationship::updateLayout()
 			}
 		}
 
-		m_line = QPolygonF() << finalLine.p1() << finalLine.p2();
+		d->line = QPolygonF() << finalLine.p1() << finalLine.p2();
 		haveLine = true;
 	}
 
 	Q_ASSERT(haveLine);
 
-	int size = m_line.size();
-	QLineF lastSegment(m_line[size-2], m_line[size-1]);
-
-	m_arrowHead.resize(3);
-	m_arrowHead[0] = QPointF(0.0, 0.0);
-	m_arrowHead[1] = QPointF(-4.5, 10.0);
-	m_arrowHead[2] = QPointF(4.5, 10.0);
-	QMatrix matrix;
-	matrix.rotate(-lastSegment.angle() + 90);
-	m_arrowHead = matrix.map(m_arrowHead);
-	m_arrowHead.translate(lastSegment.p2());
+	// "Relational"
+	if (1) {
+		d->fillEnds = true;
+		d->targetEnd = d->arrowHeadPath();
+		d->sourceEnd = QPainterPath();
+	}
+	// "Crow's Foot"
+	else {
+		d->fillEnds = false;
+		d->targetEnd = d->crowsFootPath(d->cardinality);
+		d->sourceEnd = d->crowsFootPath(isRequired() ? One : ZeroOrOne);
+	}
+
+	if (!d->sourceEnd.isEmpty()) {
+		QLineF firstSegment(d->line[0], d->line[1]);
+		QMatrix matrix;
+		matrix.translate(firstSegment.p1().x(), firstSegment.p1().y());
+		matrix.rotate(360 - firstSegment.angle() + 90 + 180);
+		d->sourceEnd = matrix.map(d->sourceEnd);
+	}
+
+	if (!d->targetEnd.isEmpty()) {
+		int size = d->line.size();
+		QLineF lastSegment(d->line[size-2], d->line[size-1]);
+		QMatrix matrix;
+		matrix.translate(lastSegment.p2().x(), lastSegment.p2().y());
+		matrix.rotate(-lastSegment.angle() + 90);
+		d->targetEnd = matrix.map(d->targetEnd);
+	}
 }
 
 #include "domutils.h"
diff --git a/src/items/database/databaserelationship.h b/src/items/database/databaserelationship.h
index 4a07e86..d8762cf 100644
--- a/src/items/database/databaserelationship.h
+++ b/src/items/database/databaserelationship.h
@@ -52,10 +52,10 @@ public:
 	void updatePositions();
 
 	//! Returns true if the foreign key on the child table is also the primary key
-	bool isIdentifying();
+	bool isIdentifying() const;
 
 	//! Returns true if the foreign key on the child table is required (NOT NULL)
-	bool isRequired();
+	bool isRequired() const;
 
 	enum Cardinality {
 		ZeroOrMore,
@@ -99,9 +99,6 @@ protected:
 private:
 	class PrivateData;
 	PrivateData *const d;
-
-	QPolygonF m_line;
-	QPolygonF m_arrowHead;
 };
 
 #endif