Added support for grabbers. Next step: actually resize rectangles when pressing grabbers

crazyflie_ws/sandbox/crazypkg/gui/untitled/cornergrabber.cpp

+#include "cornergrabber.h"
+
+CornerGrabber::CornerGrabber(QGraphicsItem *parent,  int corner) :
+    QGraphicsItem(parent),
+    mouseDownX(0),
+    mouseDownY(0),
+    _outterborderColor(Qt::black),
+    _outterborderPen(),
+    _width(6),
+    _height(6),
+    _corner(corner),
+    _mouseButtonState(kMouseReleased),
+    _is_active(false)
+{
+    setParentItem(parent);
+
+    _outterborderPen.setWidth(2);
+    _outterborderPen.setColor(_outterborderColor);
+
+   this->setAcceptHoverEvents(true);
+}
+
+qreal CornerGrabber::getHeight()
+{
+    return _height;
+}
+
+qreal CornerGrabber::getWidth()
+{
+    return _width;
+}
+
+void CornerGrabber::setMouseState(int s)
+{
+    _mouseButtonState = s;
+}
+
+int CornerGrabber::getMouseState()
+{
+    return _mouseButtonState;
+}
+
+int CornerGrabber::getCorner()
+{
+    return _corner;
+}
+
+bool CornerGrabber::isActive()
+{
+    return _is_active;
+}
+
+
+// we have to implement the mouse events to keep the linker happy,
+// but just set accepted to false since are not actually handling them
+
+void CornerGrabber::mouseMoveEvent(QGraphicsSceneDragDropEvent *event)
+{
+    event->setAccepted(false);
+}
+
+void CornerGrabber::mousePressEvent(QGraphicsSceneDragDropEvent *event)
+{
+    event->setAccepted(false);
+}
+
+void CornerGrabber::mouseReleaseEvent ( QGraphicsSceneMouseEvent * event )
+{
+    event->setAccepted(false);
+}
+
+void CornerGrabber::mousePressEvent ( QGraphicsSceneMouseEvent * event )
+{
+    event->setAccepted(false);
+}
+
+void CornerGrabber::mouseMoveEvent ( QGraphicsSceneMouseEvent * event )
+{
+    event->setAccepted(false);
+}
+
+
+// change the color on hover events to indicate to the use the object has
+// been captured by the mouse
+
+void CornerGrabber::hoverLeaveEvent ( QGraphicsSceneHoverEvent * )
+{
+    _outterborderColor = Qt::black;
+    _is_active = false;
+    this->update(0,0,_width,_height);
+}
+
+void CornerGrabber::hoverEnterEvent ( QGraphicsSceneHoverEvent * )
+{
+    _outterborderColor = Qt::red;
+    _is_active = true;
+    this->update(0,0,_width,_height);
+}
+
+QRectF CornerGrabber::boundingRect() const
+{
+    return QRectF(0,0,_width,_height);
+}
+
+
+void CornerGrabber::paint (QPainter *painter, const QStyleOptionGraphicsItem *, QWidget *)
+{
+
+    // fill the box with solid color, use sharp corners
+
+    _outterborderPen.setCapStyle(Qt::SquareCap);
+    _outterborderPen.setStyle(Qt::SolidLine);
+    painter->setPen(_outterborderPen);
+
+    QPointF topLeft (0, 0);
+    QPointF bottomRight ( _width, _height);
+
+    QRectF rect (topLeft, bottomRight);
+
+    QBrush brush (Qt::SolidPattern);
+    brush.setColor (_outterborderColor);
+    painter->fillRect(rect,brush);
+
+}

crazyflie_ws/sandbox/crazypkg/gui/untitled/cornergrabber.h

+#ifndef CORNERGRABBER_H
+#define CORNERGRABBER_H
+
+#include <QObject>
+#include <QGraphicsItem>
+#include <QGraphicsRectItem>
+#include <QGraphicsTextItem>
+#include <QGraphicsSceneHoverEvent>
+#include <QGraphicsSceneMouseEvent>
+#include <QColor>
+#include <QPainter>
+#include <QPen>
+#include <QPointF>
+
+
+
+class CornerGrabber : public QGraphicsItem
+{
+
+public:
+    explicit CornerGrabber(QGraphicsItem *parent = 0,  int corner = 0);
+
+    int getCorner(); ///< allows the owner to find out which coner this is
+    void setMouseState(int); ///< allows the owner to record the current mouse state
+    int  getMouseState(); ///< allows the owner to get the current mouse state
+    qreal getHeight();
+    qreal getWidth();
+    bool isActive();
+
+    qreal mouseDownX;
+    qreal mouseDownY;
+
+    enum {kMouseReleased=0, kMouseDown, kMouseMoving}; ///< define the mouse states
+    enum {bottomLeft, topLeft, topRight, bottomRight};
+
+
+private:
+
+    virtual QRectF boundingRect() const; ///< must be re-implemented in this class to provide the diminsions of the box to the QGraphicsView
+    virtual void paint (QPainter *painter, const QStyleOptionGraphicsItem *option, QWidget *widget); ///< must be re-implemented here to pain the box on the paint-event
+    virtual void hoverEnterEvent ( QGraphicsSceneHoverEvent * event ); ///< must be re-implemented to handle mouse hover enter events
+    virtual void hoverLeaveEvent ( QGraphicsSceneHoverEvent * event ); ///< must be re-implemented to handle mouse hover leave events
+
+    // once the hover event handlers are implemented in this class,
+    // the mouse events must allow be implemented because of
+    // some linkage issue - apparrently there is some connection
+    // between the hover events and mouseMove/Press/Release
+    // events which triggers a vtable issue
+    virtual void mouseMoveEvent ( QGraphicsSceneMouseEvent * event );
+    virtual void mouseMoveEvent(QGraphicsSceneDragDropEvent *event);
+    virtual void mousePressEvent (QGraphicsSceneMouseEvent * event );
+    virtual void mousePressEvent(QGraphicsSceneDragDropEvent *event);
+    virtual void mouseReleaseEvent (QGraphicsSceneMouseEvent * event );
+
+    QColor _outterborderColor; ///< the hover event handlers will toggle this between red and black
+    QPen _outterborderPen; ///< the pen is used to paint the red/black border
+
+    qreal   _width;
+    qreal   _height;
+
+    int _corner;// 0,1,2,3  - starting at x=0,y=0 and moving clockwise around the box
+
+    bool _is_active;
+
+    int _mouseButtonState;
+
+
+};
+
+#endif // CORNERGRABBER_H

crazyflie_ws/sandbox/crazypkg/gui/untitled/mainguiwindow.cpp

@@ -6,7 +6,6 @@
 #include <QString>
 
 
-
 #define N_MAX_CRAZYFLIES           20 // protection number
 
 #ifndef DEBUG_GUI
@@ -58,13 +57,15 @@ void MainGUIWindow::_init()
     scene = new myGraphicsScene(ui->frame_drawing);
     //scene->setSceneRect(QRectF(QPointF(-100, 100), QSizeF(200, 200)));
 
-    ui->graphicsView->setScene(scene);
+    ui->graphicsView->setViewportUpdateMode(QGraphicsView::FullViewportUpdate);
     item1 = new QGraphicsRectItem(0,0,100,100);
     item1->setBrush(QBrush(Qt::blue));
     scene->addText("Hello world!");
     // scene->addRect(rect, QPen(Qt::black), QBrush(Qt::blue));
     scene->addItem(item1);
 
+    ui->graphicsView->setScene(scene);
+
     ui->spinBoxNumCrazyflies->setMaximum(N_MAX_CRAZYFLIES);
     _refresh_tabs();
 }

crazyflie_ws/sandbox/crazypkg/gui/untitled/moc_renderarea.cpp

-/****************************************************************************
-** Meta object code from reading C++ file 'renderarea.h'
-**
-** Created by: The Qt Meta Object Compiler version 67 (Qt 5.7.0)
-**
-** WARNING! All changes made in this file will be lost!
-*****************************************************************************/
-
-#include "renderarea.h"
-#include <QtCore/qbytearray.h>
-#include <QtCore/qmetatype.h>
-#if !defined(Q_MOC_OUTPUT_REVISION)
-#error "The header file 'renderarea.h' doesn't include <QObject>."
-#elif Q_MOC_OUTPUT_REVISION != 67
-#error "This file was generated using the moc from 5.7.0. It"
-#error "cannot be used with the include files from this version of Qt."
-#error "(The moc has changed too much.)"
-#endif
-
-QT_BEGIN_MOC_NAMESPACE
-struct qt_meta_stringdata_RenderArea_t {
-    QByteArrayData data[13];
-    char stringdata0[113];
-};
-#define QT_MOC_LITERAL(idx, ofs, len) \
-    Q_STATIC_BYTE_ARRAY_DATA_HEADER_INITIALIZER_WITH_OFFSET(len, \
-    qptrdiff(offsetof(qt_meta_stringdata_RenderArea_t, stringdata0) + ofs \
-        - idx * sizeof(QByteArrayData)) \
-    )
-static const qt_meta_stringdata_RenderArea_t qt_meta_stringdata_RenderArea = {
-    {
-QT_MOC_LITERAL(0, 0, 10), // "RenderArea"
-QT_MOC_LITERAL(1, 11, 8), // "setShape"
-QT_MOC_LITERAL(2, 20, 0), // ""
-QT_MOC_LITERAL(3, 21, 5), // "Shape"
-QT_MOC_LITERAL(4, 27, 5), // "shape"
-QT_MOC_LITERAL(5, 33, 6), // "setPen"
-QT_MOC_LITERAL(6, 40, 3), // "pen"
-QT_MOC_LITERAL(7, 44, 8), // "setBrush"
-QT_MOC_LITERAL(8, 53, 5), // "brush"
-QT_MOC_LITERAL(9, 59, 14), // "setAntialiased"
-QT_MOC_LITERAL(10, 74, 11), // "antialiased"
-QT_MOC_LITERAL(11, 86, 14), // "setTransformed"
-QT_MOC_LITERAL(12, 101, 11) // "transformed"
-
-    },
-    "RenderArea\0setShape\0\0Shape\0shape\0"
-    "setPen\0pen\0setBrush\0brush\0setAntialiased\0"
-    "antialiased\0setTransformed\0transformed"
-};
-#undef QT_MOC_LITERAL
-
-static const uint qt_meta_data_RenderArea[] = {
-
- // content:
-       7,       // revision
-       0,       // classname
-       0,    0, // classinfo
-       5,   14, // methods
-       0,    0, // properties
-       0,    0, // enums/sets
-       0,    0, // constructors
-       0,       // flags
-       0,       // signalCount
-
- // slots: name, argc, parameters, tag, flags
-       1,    1,   39,    2, 0x0a /* Public */,
-       5,    1,   42,    2, 0x0a /* Public */,
-       7,    1,   45,    2, 0x0a /* Public */,
-       9,    1,   48,    2, 0x0a /* Public */,
-      11,    1,   51,    2, 0x0a /* Public */,
-
- // slots: parameters
-    QMetaType::Void, 0x80000000 | 3,    4,
-    QMetaType::Void, QMetaType::QPen,    6,
-    QMetaType::Void, QMetaType::QBrush,    8,
-    QMetaType::Void, QMetaType::Bool,   10,
-    QMetaType::Void, QMetaType::Bool,   12,
-
-       0        // eod
-};
-
-void RenderArea::qt_static_metacall(QObject *_o, QMetaObject::Call _c, int _id, void **_a)
-{
-    if (_c == QMetaObject::InvokeMetaMethod) {
-        RenderArea *_t = static_cast<RenderArea *>(_o);
-        Q_UNUSED(_t)
-        switch (_id) {
-        case 0: _t->setShape((*reinterpret_cast< Shape(*)>(_a[1]))); break;
-        case 1: _t->setPen((*reinterpret_cast< const QPen(*)>(_a[1]))); break;
-        case 2: _t->setBrush((*reinterpret_cast< const QBrush(*)>(_a[1]))); break;
-        case 3: _t->setAntialiased((*reinterpret_cast< bool(*)>(_a[1]))); break;
-        case 4: _t->setTransformed((*reinterpret_cast< bool(*)>(_a[1]))); break;
-        default: ;
-        }
-    }
-}
-
-const QMetaObject RenderArea::staticMetaObject = {
-    { &QWidget::staticMetaObject, qt_meta_stringdata_RenderArea.data,
-      qt_meta_data_RenderArea,  qt_static_metacall, Q_NULLPTR, Q_NULLPTR}
-};
-
-
-const QMetaObject *RenderArea::metaObject() const
-{
-    return QObject::d_ptr->metaObject ? QObject::d_ptr->dynamicMetaObject() : &staticMetaObject;
-}
-
-void *RenderArea::qt_metacast(const char *_clname)
-{
-    if (!_clname) return Q_NULLPTR;
-    if (!strcmp(_clname, qt_meta_stringdata_RenderArea.stringdata0))
-        return static_cast<void*>(const_cast< RenderArea*>(this));
-    return QWidget::qt_metacast(_clname);
-}
-
-int RenderArea::qt_metacall(QMetaObject::Call _c, int _id, void **_a)
-{
-    _id = QWidget::qt_metacall(_c, _id, _a);
-    if (_id < 0)
-        return _id;
-    if (_c == QMetaObject::InvokeMetaMethod) {
-        if (_id < 5)
-            qt_static_metacall(this, _c, _id, _a);
-        _id -= 5;
-    } else if (_c == QMetaObject::RegisterMethodArgumentMetaType) {
-        if (_id < 5)
-            *reinterpret_cast<int*>(_a[0]) = -1;
-        _id -= 5;
-    }
-    return _id;
-}
-QT_END_MOC_NAMESPACE

crazyflie_ws/sandbox/crazypkg/gui/untitled/myGraphicsRectItem.cpp

+#include "myGraphicsRectItem.h"
+
+#include <QGraphicsSceneMouseEvent>
+#include <QGraphicsRectItem>
+#include <QPen>
+#include <QBrush>
+#include <QApplication>
+#include <QVariant>
+
+myGraphicsRectItem::myGraphicsRectItem(const QRectF & rect, QGraphicsItem * parent)
+    : QGraphicsRectItem(rect, parent)
+{
+    this->setFlag(QGraphicsItem::ItemIsSelectable);
+    this->setFlag(QGraphicsItem::ItemIsMovable);
+    pen = new QPen(Qt::red);
+    brush = new QBrush(Qt::red);
+
+    tmp_rect = 0;
+    _grabbers_created = false;
+    // this->setAcceptHoverEvents(true);
+}
+
+void myGraphicsRectItem::deleteGrabbers()
+{
+    _bottomLeft_corner->setParentItem(NULL);
+    _topLeft_corner->setParentItem(NULL);
+    _topRight_corner->setParentItem(NULL);
+    _bottomRight_corner->setParentItem(NULL);
+
+    delete _bottomLeft_corner;
+    delete _topLeft_corner;
+    delete _topRight_corner;
+    delete _bottomRight_corner;
+    _grabbers_created = false;
+}
+
+QVariant myGraphicsRectItem::itemChange(GraphicsItemChange change, const QVariant &value)
+{
+    if (change == QGraphicsItem::ItemSelectedChange)
+    {
+        if (value == true)
+        {
+            qDebug("selected!");
+            createGrabbers();
+        }
+        else
+        {
+            qDebug("unselected!");
+            deleteGrabbers();
+        }
+    }
+
+    return QGraphicsItem::itemChange(change, value);
+}
+
+bool myGraphicsRectItem::grabbersAreCreated()
+{
+    return _grabbers_created;
+}
+
+void myGraphicsRectItem::setCornerPositions()
+{
+    QRectF rect = this->rect();
+
+    _bottomLeft_corner->setPos(rect.bottomLeft().x(), rect.bottomLeft().y() - _bottomLeft_corner->getHeight());
+    _topLeft_corner->setPos(rect.topLeft().x(), rect.topLeft().y());
+    _topRight_corner->setPos(rect.topRight().x() - _topRight_corner->getWidth(), rect.topRight().y());
+    _bottomRight_corner->setPos(rect.bottomRight().x() - _bottomRight_corner->getWidth(), rect.bottomRight().y() - _bottomRight_corner->getHeight());
+}
+
+void myGraphicsRectItem::createGrabbers()
+{
+    if(!grabbersAreCreated())
+    {
+        _bottomLeft_corner = new CornerGrabber(this, CornerGrabber::bottomLeft);
+        _topLeft_corner = new CornerGrabber(this, CornerGrabber::topLeft);
+        _topRight_corner = new CornerGrabber(this, CornerGrabber::topRight);
+        _bottomRight_corner = new CornerGrabber(this, CornerGrabber::topRight);
+
+
+        _bottomLeft_corner->installSceneEventFilter(this);
+        _topLeft_corner->installSceneEventFilter(this);
+        _topRight_corner->installSceneEventFilter(this);
+        _bottomRight_corner->installSceneEventFilter(this);
+
+        _grabbers_created = true;
+        setCornerPositions();
+    }
+}
+
+int myGraphicsRectItem::checkCornerGrabbers()
+{
+
+    // we return the first active found. Hopefully we never have two at the same time.
+    if(_bottomLeft_corner->isActive())
+        return CornerGrabber::bottomLeft;
+    else if(_topLeft_corner->isActive())
+        return CornerGrabber::topLeft;
+    else if (_topRight_corner->isActive())
+        return CornerGrabber::topRight;
+    else if( _bottomRight_corner->isActive())
+        return CornerGrabber::bottomRight;
+    else
+        return 20;
+}
+
+void myGraphicsRectItem::mousePressEvent(QGraphicsSceneMouseEvent *mouseEvent)
+{
+    if (mouseEvent->button() != Qt::LeftButton)
+        return;
+
+    createGrabbers();           //This is just in case they have not been created by now.
+
+    switch(checkCornerGrabbers())
+    {
+        case CornerGrabber::bottomLeft:
+            qDebug("bottomLeft");
+            mouseEvent->setAccepted(true);
+            break;
+        case CornerGrabber::topLeft:
+            qDebug("topLeft");
+            mouseEvent->setAccepted(true);
+            break;
+        case CornerGrabber::topRight:
+            qDebug("topRight");
+            mouseEvent->setAccepted(true);
+            break;
+        case CornerGrabber::bottomRight:
+            qDebug("bottomRight");
+            mouseEvent->setAccepted(true);
+            break;
+        default:
+            qDebug("No corner");
+            // Normal case here, mouse not in corner grabbers
+            QGraphicsRectItem::mousePressEvent(mouseEvent);
+            break;
+    }
+    // TODO: check if over handlers, if, resize mode
+}
+
+void myGraphicsRectItem::mouseMoveEvent(QGraphicsSceneMouseEvent *mouseEvent)
+{
+    this->prepareGeometryChange();
+    QGraphicsRectItem::mouseMoveEvent(mouseEvent);
+}
+
+void myGraphicsRectItem::mouseReleaseEvent(QGraphicsSceneMouseEvent *mouseEvent)
+{
+
+    if (mouseEvent->button() != Qt::LeftButton)
+        return;
+    // TODO: stop resize mode
+    QGraphicsRectItem::mouseReleaseEvent(mouseEvent);
+}

crazyflie_ws/sandbox/crazypkg/gui/untitled/myGraphicsRectItem.h

+#ifndef MYGRAPHICSRECTITEM_H
+#define MYGRAPHICSRECTITEM_H
+#include <vector>
+
+#include <QGraphicsRectItem>
+#include "cornergrabber.h"
+
+class QGraphicsSceneMouseEvent;
+class QPointF;
+class QColor;
+
+
+class myGraphicsRectItem : public QGraphicsRectItem
+{
+public:
+    explicit myGraphicsRectItem(const QRectF & rect, QGraphicsItem * parent = 0);
+
+public slots:
+
+signals:
+
+protected:
+    void mousePressEvent(QGraphicsSceneMouseEvent *mouseEvent) override;
+    void mouseMoveEvent(QGraphicsSceneMouseEvent *mouseEvent) override;
+    void mouseReleaseEvent(QGraphicsSceneMouseEvent *mouseEvent) override;
+
+    QVariant itemChange(GraphicsItemChange change, const QVariant &value) override;
+
+private:
+    void setCornerPositions();
+    int checkCornerGrabbers();
+    void createGrabbers();
+    bool grabbersAreCreated();
+    void deleteGrabbers();
+
+    QPen* pen;
+    QBrush* brush;
+    QRectF* tmp_rect;
+    QGraphicsRectItem* tmp_rect_item;
+    QPointF* p1;
+    QPointF* p2;
+
+    CornerGrabber* _bottomLeft_corner;
+    CornerGrabber* _topLeft_corner;
+    CornerGrabber* _topRight_corner;
+    CornerGrabber* _bottomRight_corner;
+
+    bool _grabbers_created;
+};
+
+#endif

crazyflie_ws/sandbox/crazypkg/gui/untitled/myGraphicsScene.cpp

@@ -2,7 +2,7 @@
 
 #include <QGraphicsSceneMouseEvent>
 #include <QRect>
-#include <QGraphicsRectItem>
+#include <QApplication>
 
 myGraphicsScene::myGraphicsScene(QObject *parent)
     : QGraphicsScene(parent)
@@ -15,38 +15,20 @@ myGraphicsScene::myGraphicsScene(QObject *parent)