edge adjust() calculates endpoints correctly (with brute force :P), no arrow if the line is too short, no line if the nodes collide

edge.cpp

@@ -1,4 +1,6 @@
 #include <QPainter>
+#include <QDebug>
+
 
 #include "edge.h"
 #include "node.h"
@@ -17,7 +19,7 @@ Edge::Edge(Node *sourceNode, Node *destNode)
     source->addEdge(this);
     dest->addEdge(this);
     adjust();
-    setZValue(1);
+//    setZValue(1);
 }
 
 Node *Edge::sourceNode() const
@@ -30,28 +32,57 @@ Node *Edge::destNode() const
     return dest;
 }
 
+/// @note This is brute force. Isn't there a simple fv for this?
+QPointF firstNotContainedPoint(const QLineF &line,
+                               const QPointF &pos,
+                               const QRectF &rectangle,
+                               bool reverse = false)
+{
+    QRectF rect(rectangle.topLeft()+pos, rectangle.bottomRight()+pos);
+    if (reverse)
+    {
+        for (qreal t = 1; t!=0; t-=0.01)
+        {
+            if (!rect.contains(line.pointAt(t))) return line.pointAt(t);
+        }
+    }
+    else
+    {
+        for (qreal t = 0; t!=1; t+=0.01)
+        {
+            if (!rect.contains(line.pointAt(t))) return line.pointAt(t);
+        }
+    }
+    return QPoint(0,0);
+}
+
 void Edge::adjust()
 {
     if (!source || !dest)
         return;
 
+
+    prepareGeometryChange();
+
     QLineF line(mapFromItem(source, 0, 0) + source->boundingRect().center(),
                 mapFromItem(dest, 0, 0)  + dest->boundingRect().center());
     qreal length = line.length();
 
-    prepareGeometryChange();
+
 
     if (length > qreal(20.)) {
-//        QPointF edgeOffset((line.dx() * 10) / length, (line.dy() * 10) / length);
-//        QPointF sourceOffset( );
-//        if ( source->contains( source->boundingRect().center() + source->boundingRect().height() / 2 / tan(line.angle())),
-//                               source->boundingRect().width() / 2 )
-//        {
-//             sourcePoint = line.p1() +  QPointF(  , tan( line.angle() ) * source->boundingRect().height() / 2 );
-//        }
-
-        sourcePoint = line.p1();
-        destPoint = line.p2();
+
+        QPointF sourceOffset(firstNotContainedPoint(line,
+                                                    source->pos(),
+                                                    source->boundingRect()
+                                                    ));
+        QPointF destOffset(firstNotContainedPoint(line,
+                                                  dest->pos(),
+                                                  dest->boundingRect()
+                                                  ,true));
+
+        sourcePoint = sourceOffset;
+        destPoint = destOffset;
     } else {
         sourcePoint = destPoint = line.p1();
     }
@@ -77,13 +108,21 @@ void Edge::paint(QPainter *painter, const QStyleOptionGraphicsItem *, QWidget *)
         return;
 
     QLineF line(sourcePoint, destPoint);
-    if (qFuzzyCompare(line.length(), qreal(0.)))
+
+    /// @bug this test does not filter out when the nodes intersect
+//    if (qFuzzyCompare(line.length(), qreal(0.)))
+//        return;
+
+    if (sourceNode()->collidesWithItem(destNode()))
         return;
 
     // Draw the line itself
     painter->setPen(QPen(Qt::black, 1, Qt::SolidLine, Qt::RoundCap, Qt::RoundJoin));
     painter->drawLine(line);
 
+    if (line.length() < qreal(10.))
+        return;
+
     // Draw the arrows
     double angle = ::acos(line.dx() / line.length());
     if (line.dy() >= 0)

graphwidget.cpp

@@ -12,51 +12,52 @@ GraphWidget::GraphWidget(QWidget *parent)
 
     scene = new QGraphicsScene(this);
     scene->setItemIndexMethod(QGraphicsScene::NoIndex);
-    scene->setSceneRect(-200, -200, 400, 400);
+    scene->setSceneRect(-400, -400, 800, 800);
     setScene(scene);
     setCacheMode(CacheBackground);
     setViewportUpdateMode(BoundingRectViewportUpdate);
     setRenderHint(QPainter::Antialiasing);
     setTransformationAnchor(AnchorUnderMouse);
-    scale(qreal(0.8), qreal(0.8));
     setMinimumSize(400, 400);
 
-
-//    node1 = new Node(this);
-//    scene->addItem(node1);
-//    node1->setPos(0, 0);
     Node *node1 = new Node();
-    node1->setHtml(QString("salalal"));
+    node1->setHtml(QString("me"));
     scene->addItem(node1);
-    node1->setPos(-100, -100);
+    node1->setPos(-10, -10);
 
     Node *node2 = new Node();
-    node2->setHtml(QString("<b>denes</b> is\na really nice person"));
+    node2->setHtml(QString("work"));
     scene->addItem(node2);
-    node2->setPos(100, 100);
-
-
-//    QGraphicsTextItem *item = new QGraphicsTextItem();
-//    item->setPlainText(QString("salalal"));
-//    scene->addItem(item);
-//    item->setPos(20, 20);
-//    item->setFlag(QGraphicsItem::ItemIsMovable);
-//    item->setFlag(QGraphicsItem::ItemSendsGeometryChanges);
-//    item->setCacheMode(QGraphicsItem::DeviceCoordinateCache);
-//    item->setZValue(-1);
-
-//    QGraphicsTextItem *item2 = new QGraphicsTextItem();
-//    item2->setHtml(QString("<b>denes</b> is\na really nice person"));
-//    scene->addItem(item2);
-//    item2->setPos(10, 10);
-//    item2->setFlag(QGraphicsItem::ItemIsMovable);
-//    item2->setFlag(QGraphicsItem::ItemSendsGeometryChanges);
-//    item2->setCacheMode(QGraphicsItem::DeviceCoordinateCache);
-//    item2->setZValue(-1);
-
-  scene->addItem(new Edge(node1, node2));
-  activeNode = node1;
-  activeNode->setFocus();
+    node2->setPos(60, -10);
+
+    Node *node3 = new Node();
+    node3->setHtml(QString("read"));
+    scene->addItem(node3);
+    node3->setPos(-70, -10);
+
+    Node *node4 = new Node();
+    node4->setHtml(QString("pragmatic programmer"));
+    scene->addItem(node4);
+    node4->setPos(-120, -80);
+
+    Node *node5 = new Node();
+    node5->setHtml(QString("joy"));
+    scene->addItem(node5);
+    node5->setPos(-10, 50);
+
+    Node *node6 = new Node();
+    node6->setHtml(QString("rape goats"));
+    scene->addItem(node6);
+    node6->setPos(-10, 100);
+
+    scene->addItem(new Edge(node1, node2));
+    scene->addItem(new Edge(node1, node3));
+    scene->addItem(new Edge(node3, node4));
+    scene->addItem(new Edge(node1, node5));
+    scene->addItem(new Edge(node5, node6));
+
+    activeNode = node1;
+    activeNode->setFocus();
 }
 
 QGraphicsScene *GraphWidget::getScene()
@@ -102,6 +103,44 @@ void GraphWidget::wheelEvent(QWheelEvent *event)
     scaleView(pow((double)2, -event->delta() / 240.0));
 }
 
+void GraphWidget::drawBackground(QPainter *painter, const QRectF &rect)
+ {
+     Q_UNUSED(rect);
+
+     // Shadow
+     QRectF sceneRect = this->sceneRect();
+//     QRectF rightShadow(sceneRect.right(), sceneRect.top() + 5, 5, sceneRect.height());
+//     QRectF bottomShadow(sceneRect.left() + 5, sceneRect.bottom(), sceneRect.width(), 5);
+//     if (rightShadow.intersects(rect) || rightShadow.contains(rect))
+//         painter->fillRect(rightShadow, Qt::darkGray);
+//     if (bottomShadow.intersects(rect) || bottomShadow.contains(rect))
+//         painter->fillRect(bottomShadow, Qt::darkGray);
+
+     // Fill
+     QLinearGradient gradient(sceneRect.topLeft(), sceneRect.bottomRight());
+     gradient.setColorAt(0, Qt::white);
+     gradient.setColorAt(1, Qt::lightGray);
+     painter->fillRect(rect.intersect(sceneRect), gradient);
+     painter->setBrush(Qt::NoBrush);
+     painter->drawRect(sceneRect);
+
+//     // Text
+//     QRectF textRect(sceneRect.left() + 4, sceneRect.top() + 4,
+//                     sceneRect.width() - 4, sceneRect.height() - 4);
+//     QString message(tr("Click and drag the nodes around, and zoom with the mouse "
+//                        "wheel or the '+' and '-' keys"));
+
+//     QFont font = painter->font();
+//     font.setBold(true);
+//     font.setPointSize(14);
+//     painter->setFont(font);
+//     painter->setPen(Qt::lightGray);
+//     painter->drawText(textRect.translated(2, 2), message);
+//     painter->setPen(Qt::black);
+//     painter->drawText(textRect, message);
+ }
+
+
 void GraphWidget::scaleView(qreal scaleFactor)
 {
     qreal factor = transform().scale(scaleFactor, scaleFactor).mapRect(QRectF(0, 0, 1, 1)).width();

graphwidget.h

@@ -21,6 +21,7 @@ protected:
     void keyPressEvent(QKeyEvent *event);
     void wheelEvent(QWheelEvent *event);
     void scaleView(qreal scaleFactor);
+    void drawBackground(QPainter *painter, const QRectF &rect);
 
 private:
     Node *activeNode;

mainwindow.cpp

@@ -3,9 +3,32 @@
 #include "aboutdialog.h"
 
 #include <QDebug>
-//#include <QLayout>
 #include <QFileDialog>
 
+//#include <QtConcurrentRun>
+
+/// QPixmap: It is not safe to use pixmaps outside the GUI thread
+/// tr is messy
+/*
+extern void exportScaneToPng(QGraphicsScene *scene,
+                             const QString &fileName,
+                             Ui::MainWindow *ui)
+{
+    // start export in a diff thread
+    QImage img(scene->sceneRect().width(),
+               scene->sceneRect().height(),
+               QImage::Format_ARGB32_Premultiplied);
+    QPainter painter(&img);
+    painter.setRenderHint(QPainter::Antialiasing);
+    scene->render(&painter);
+    painter.end();
+
+    img.save(fileName);
+    ui->statusBar->showMessage(tr("MindMap exported as ") + fileName,
+                               5000); // millisec
+}
+*/
+
 
 MainWindow::MainWindow(bool isSystemtray, QWidget *parent) :
     QMainWindow(parent),
@@ -58,18 +81,26 @@ void MainWindow::exportScene()
      {
          QStringList fileNames(dialog.selectedFiles());
 
-         // start export in a diff thread
+         /// @note Shall I start the export in diff thread?
+//         QtConcurrent::run(exportScaneToPng,
+//                           graphicsView->getScene(),
+//                           fileNames.first(),
+//                           ui);
+
          QImage img(graphicsView->getScene()->sceneRect().width(),
                     graphicsView->getScene()->sceneRect().height(),
                     QImage::Format_ARGB32_Premultiplied);
          QPainter painter(&img);
          painter.setRenderHint(QPainter::Antialiasing);
+
+         /// @bug scene background is not rendered
          graphicsView->getScene()->render(&painter);
          painter.end();
 
          img.save(fileNames.first());
          ui->statusBar->showMessage(tr("MindMap exported as ") + fileNames.first(),
-                                    5000);
+                                    5000); // millisec
+
      }
 }
 

node.cpp

@@ -11,10 +11,13 @@ Node::Node(GraphWidget *parent) : graph(parent), active(false)
     setFlag(ItemIsMovable);
     setFlag(ItemSendsGeometryChanges);
     setCacheMode(DeviceCoordinateCache);
-    setZValue(2);
+//    setZValue(1);
+
+    // shall I use system colors?
+    setDefaultTextColor(QColor(0,0,0));
 
     // shall I set it after some spec key?
-    setTextInteractionFlags(Qt::TextEditorInteraction);
+//    setTextInteractionFlags(Qt::TextEditorInteraction);
 }
 
 void Node::addEdge(Edge *edge)
@@ -32,8 +35,8 @@ QVariant Node::itemChange(GraphicsItemChange change, const QVariant &value)
 
     switch (change) {
         case ItemPositionHasChanged:
+
             foreach (Edge *edge, edgeList) edge->adjust();
-            //         graph->itemMoved();
             break;
         default:
             break;
@@ -56,18 +59,32 @@ void Node::mouseReleaseEvent(QGraphicsSceneMouseEvent *event)
 {
     qDebug() << __PRETTY_FUNCTION__;
 
-//    active = false;
-//    setScale(1.0);
     update();
     QGraphicsTextItem::mouseReleaseEvent(event);
 }
 
-//void Node::paint(QPainter *painter, const QStyleOptionGraphicsItem *option, QWidget *widget)
-//{
-//    qDebug() << __PRETTY_FUNCTION__;
-//    QGraphicsTextItem::paint(painter, option, widget);
 
-//    qDebug() << "I " << (hasFocus() ? "have " : "don't have ") << "focus.";
-//    setScale(hasFocus() ? 1.2 : 1.0);
-////    setScale(active ? 1.2 : 1.0);
-//}
+void Node::paint(QPainter *painter, const QStyleOptionGraphicsItem *option, QWidget *w)
+{
+        qDebug() << __PRETTY_FUNCTION__;
+
+        QGraphicsTextItem::paint(painter, option, w);
+
+        QPen pen(Qt::blue,1);
+//        pen.setJoinStyle(Qt::RoundJoin);
+//        pen.setStyle(Qt::MiterJoin);
+//        pen.setCapStyle(Qt::RoundCap);
+//        pen.setMiterLimit(3);
+        painter->setPen(pen);
+
+//        painter->setPen(QPen(Qt::blue
+//                             , 1, Qt::SolidLine,Qt::SquareCap, Qt::RoundJoin
+//                             ));
+        m_rect = QRect(	boundingRect().topLeft().toPoint()
+//                        - QPoint(4,4)
+                        ,
+                        boundingRect().bottomRight().toPoint()
+                        - QPoint(1,1)
+                        );
+        painter->drawRect(m_rect);
+}

node.h

@@ -8,6 +8,7 @@
 
 class GraphWidget;
 
+/// @bug no signal when size change
 class Node : public QGraphicsTextItem
 {
 //    Q_OBJECT
@@ -22,12 +23,14 @@ protected:
     QVariant itemChange(GraphicsItemChange change, const QVariant &value);
     void mousePressEvent(QGraphicsSceneMouseEvent *event);
     void mouseReleaseEvent(QGraphicsSceneMouseEvent *event);
-//    void paint(QPainter *painter, const QStyleOptionGraphicsItem *option, QWidget *widget);
+    void paint(QPainter *painter, const QStyleOptionGraphicsItem *option, QWidget *widget);
+
 
 private:
     QList<Edge *> edgeList;
     GraphWidget *graph;
     bool active;
+    QRectF m_rect;
 
 };