Qt:Документация 4.3.2/graphicsview-portedcanvas-canvas-cpp
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[править] canvas.cpp Example File
graphicsview/portedcanvas/canvas.cpp
/**************************************************************************** ** ** Copyright (C) 2006-2007 Trolltech ASA. All rights reserved. ** ** This file is part of the example classes of the Qt Toolkit. ** ** This file may be used under the terms of the GNU General Public ** License version 2.0 as published by the Free Software Foundation ** and appearing in the file LICENSE.GPL included in the packaging of ** this file. Please review the following information to ensure GNU ** General Public Licensing requirements will be met: ** http://trolltech.com/products/qt/licenses/licensing/opensource/ ** ** If you are unsure which license is appropriate for your use, please ** review the following information: ** http://trolltech.com/products/qt/licenses/licensing/licensingoverview ** or contact the sales department at sales@trolltech.com. ** ** In addition, as a special exception, Trolltech gives you certain ** additional rights. These rights are described in the Trolltech GPL ** Exception version 1.0, which can be found at ** http://www.trolltech.com/products/qt/gplexception/ and in the file ** GPL_EXCEPTION.txt in this package. ** ** In addition, as a special exception, Trolltech, as the sole copyright ** holder for Qt Designer, grants users of the Qt/Eclipse Integration ** plug-in the right for the Qt/Eclipse Integration to link to ** functionality provided by Qt Designer and its related libraries. ** ** Trolltech reserves all rights not expressly granted herein. ** ** Trolltech ASA (c) 2007 ** ** This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE ** WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. ** ****************************************************************************/ #include <qdatetime.h> #include <qmainwindow.h> #include <qstatusbar.h> #include <qmessagebox.h> #include <qmenubar.h> #include <qapplication.h> #include <qpainter.h> #include <qprinter.h> #include <qlabel.h> #include <qimage.h> #include <q3progressdialog.h> #include <Q3PointArray> #include <Q3PtrList> #include <QPixmap> #include <Q3PopupMenu> #include <QMouseEvent> #include <Q3MemArray> #include "canvas.h" #include <QStyleOptionGraphicsItem> #include <qdebug.h> #include <stdlib.h> // We use a global variable to save memory - all the brushes and pens in // the mesh are shared. static QBrush *tb = 0; static QPen *tp = 0; class EdgeItem; class NodeItem; class EdgeItem: public QGraphicsLineItem { public: EdgeItem( NodeItem*, NodeItem* ); void setFromPoint( int x, int y ) ; void setToPoint( int x, int y ); static int count() { return c; } private: static int c; }; static const int imageRTTI = 984376; class ImageItem: public QGraphicsRectItem { public: ImageItem( QImage img ); int rtti () const { return imageRTTI; } protected: void paint( QPainter *, const QStyleOptionGraphicsItem *option, QWidget *widget ); private: QImage image; QPixmap pixmap; }; ImageItem::ImageItem( QImage img ) : image(img) { setRect(0, 0, image.width(), image.height()); setFlag(ItemIsMovable); #if !defined(Q_WS_QWS) pixmap.convertFromImage(image, Qt::OrderedAlphaDither); #endif } void ImageItem::paint( QPainter *p, const QStyleOptionGraphicsItem *option, QWidget * ) { // On Qt/Embedded, we can paint a QImage as fast as a QPixmap, // but on other platforms, we need to use a QPixmap. #if defined(Q_WS_QWS) p->drawImage( option->exposedRect, image, option->exposedRect, Qt::OrderedAlphaDither ); #else p->drawPixmap( option->exposedRect, pixmap, option->exposedRect ); #endif } class NodeItem: public QGraphicsEllipseItem { public: NodeItem(); ~NodeItem() {} void addInEdge( EdgeItem *edge ) { inList.append( edge ); } void addOutEdge( EdgeItem *edge ) { outList.append( edge ); } protected: QVariant itemChange(GraphicsItemChange change, const QVariant &value); // QPoint center() { return boundingRect().center(); } private: Q3PtrList<EdgeItem> inList; Q3PtrList<EdgeItem> outList; }; int EdgeItem::c = 0; EdgeItem::EdgeItem( NodeItem *from, NodeItem *to ) : QGraphicsLineItem( ) { c++; setPen( *tp ); from->addOutEdge( this ); to->addInEdge( this ); setLine( QLineF(int(from->x()), int(from->y()), int(to->x()), int(to->y()) )); setZValue( 127 ); } void EdgeItem::setFromPoint( int x, int y ) { setLine(QLineF( x,y, line().p2().x(), line().p2().y() )); } void EdgeItem::setToPoint( int x, int y ) { setLine(QLineF( line().p1().x(), line().p1().y(), x, y )); } QVariant NodeItem::itemChange(GraphicsItemChange change, const QVariant &value) { if (change == ItemPositionHasChanged) { Q3PtrListIterator<EdgeItem> it1( inList ); EdgeItem *edge; while (( edge = it1.current() )) { ++it1; edge->setToPoint( int(x()), int(y()) ); } Q3PtrListIterator<EdgeItem> it2( outList ); while (( edge = it2.current() )) { ++it2; edge->setFromPoint( int(x()), int(y()) ); } } return QGraphicsEllipseItem::itemChange(change, value); } NodeItem::NodeItem( ) : QGraphicsEllipseItem( QRectF(-3, -3, 6, 6) ) { setPen( *tp ); setBrush( *tb ); setZValue( 128 ); setFlag(ItemIsMovable); } FigureEditor::FigureEditor( QGraphicsScene& c, QWidget* parent, const char* name, Qt::WindowFlags f) : QGraphicsView(&c,parent) { setObjectName(name); setWindowFlags(f); setRenderHints(QPainter::Antialiasing | QPainter::SmoothPixmapTransform); } void FigureEditor::clear() { QList<QGraphicsItem *> list = scene()->items(); QList<QGraphicsItem *>::Iterator it = list.begin(); for (; it != list.end(); ++it) { if ( *it ) delete *it; } } BouncyLogo::BouncyLogo() : xvel(0), yvel(0) { setPixmap(QPixmap(":/trolltech/examples/graphicsview/portedcanvas/qt-trans.xpm")); } const int logo_rtti = 1234; int BouncyLogo::type() const { return logo_rtti; } QPainterPath BouncyLogo::shape() const { QPainterPath path; path.addRect(boundingRect()); return path; } void BouncyLogo::initPos() { initSpeed(); int trial=1000; do { setPos(qrand()%int(scene()->width()),qrand()%int(scene()->height())); advance(0); } while (trial-- && xvel==0.0 && yvel==0.0); } void BouncyLogo::initSpeed() { const double speed = 4.0; double d = (double)(qrand()%1024) / 1024.0; xvel = d*speed*2-speed; yvel = (1-d)*speed*2-speed; } void BouncyLogo::advance(int stage) { switch ( stage ) { case 0: { double vx = xvel; double vy = yvel; if ( vx == 0.0 && vy == 0.0 ) { // stopped last turn initSpeed(); vx = xvel; vy = yvel; } double nx = x() + vx; double ny = y() + vy; if ( nx < 0 || nx >= scene()->width() ) vx = -vx; if ( ny < 0 || ny >= scene()->height() ) vy = -vy; for (int bounce=0; bounce<4; bounce++) { QList<QGraphicsItem *> l=scene()->collidingItems(this); for (QList<QGraphicsItem *>::Iterator it=l.begin(); it!=l.end(); ++it) { QGraphicsItem *hit = *it; QPainterPath advancedShape = QMatrix().translate(xvel, yvel).map(shape()); if ( hit->type()==logo_rtti && hit->collidesWithPath(mapToItem(hit, advancedShape)) ) { switch ( bounce ) { case 0: vx = -vx; break; case 1: vy = -vy; vx = -vx; break; case 2: vx = -vx; break; case 3: // Stop for this turn vx = 0; vy = 0; break; } xvel = vx; yvel = vy; break; } } } if ( x()+vx < 0 || x()+vx >= scene()->width() ) vx = 0; if ( y()+vy < 0 || y()+vy >= scene()->height() ) vy = 0; xvel = vx; yvel = vy; } break; case 1: moveBy(xvel, yvel); break; } } static uint mainCount = 0; static QImage *butterflyimg; static QImage *logoimg; Main::Main(QGraphicsScene& c, QWidget* parent, const char* name, Qt::WindowFlags f) : Q3MainWindow(parent,name,f), canvas(c) { editor = new FigureEditor(canvas,this); QMenuBar* menu = menuBar(); Q3PopupMenu* file = new Q3PopupMenu( menu ); file->insertItem("&Fill canvas", this, SLOT(init()), Qt::CTRL+Qt::Key_F); file->insertItem("&Erase canvas", this, SLOT(clear()), Qt::CTRL+Qt::Key_E); file->insertItem("&New view", this, SLOT(newView()), Qt::CTRL+Qt::Key_N); file->insertSeparator(); file->insertItem("&Print...", this, SLOT(print()), Qt::CTRL+Qt::Key_P); file->insertSeparator(); file->insertItem("E&xit", qApp, SLOT(quit()), Qt::CTRL+Qt::Key_Q); menu->insertItem("&File", file); Q3PopupMenu* edit = new Q3PopupMenu( menu ); edit->insertItem("Add &Circle", this, SLOT(addCircle()), Qt::ALT+Qt::Key_C); edit->insertItem("Add &Hexagon", this, SLOT(addHexagon()), Qt::ALT+Qt::Key_H); edit->insertItem("Add &Polygon", this, SLOT(addPolygon()), Qt::ALT+Qt::Key_P); edit->insertItem("Add Spl&ine", this, SLOT(addSpline()), Qt::ALT+Qt::Key_I); edit->insertItem("Add &Text", this, SLOT(addText()), Qt::ALT+Qt::Key_T); edit->insertItem("Add &Line", this, SLOT(addLine()), Qt::ALT+Qt::Key_L); edit->insertItem("Add &Rectangle", this, SLOT(addRectangle()), Qt::ALT+Qt::Key_R); edit->insertItem("Add &Sprite", this, SLOT(addSprite()), Qt::ALT+Qt::Key_S); edit->insertItem("Create &Mesh", this, SLOT(addMesh()), Qt::ALT+Qt::Key_M ); edit->insertItem("Add &Alpha-blended image", this, SLOT(addButterfly()), Qt::ALT+Qt::Key_A); menu->insertItem("&Edit", edit); Q3PopupMenu* view = new Q3PopupMenu( menu ); view->insertItem("&Enlarge", this, SLOT(enlarge()), Qt::SHIFT+Qt::CTRL+Qt::Key_Plus); view->insertItem("Shr&ink", this, SLOT(shrink()), Qt::SHIFT+Qt::CTRL+Qt::Key_Minus); view->insertSeparator(); view->insertItem("&Rotate clockwise", this, SLOT(rotateClockwise()), Qt::CTRL+Qt::Key_PageDown); view->insertItem("Rotate &counterclockwise", this, SLOT(rotateCounterClockwise()), Qt::CTRL+Qt::Key_PageUp); view->insertItem("&Zoom in", this, SLOT(zoomIn()), Qt::CTRL+Qt::Key_Plus); view->insertItem("Zoom &out", this, SLOT(zoomOut()), Qt::CTRL+Qt::Key_Minus); view->insertItem("Translate left", this, SLOT(moveL()), Qt::CTRL+Qt::Key_Left); view->insertItem("Translate right", this, SLOT(moveR()), Qt::CTRL+Qt::Key_Right); view->insertItem("Translate up", this, SLOT(moveU()), Qt::CTRL+Qt::Key_Up); view->insertItem("Translate down", this, SLOT(moveD()), Qt::CTRL+Qt::Key_Down); view->insertItem("&Mirror", this, SLOT(mirror()), Qt::CTRL+Qt::Key_Home); menu->insertItem("&View", view); menu->insertSeparator(); Q3PopupMenu* help = new Q3PopupMenu( menu ); help->insertItem("&About", this, SLOT(help()), Qt::Key_F1); help->setItemChecked(dbf_id, TRUE); menu->insertItem("&Help",help); statusBar(); setCentralWidget(editor); printer = 0; init(); } void Main::init() { clear(); static int r=24; qsrand(++r); mainCount++; butterflyimg = 0; logoimg = 0; int i; for ( i=0; i < int(canvas.width()) / 56; i++) { addButterfly(); } for ( i=0; i < int(canvas.width()) / 85; i++) { addHexagon(); } for ( i=0; i < int(canvas.width()) / 128; i++) { addLogo(); } } Main::~Main() { delete printer; if ( !--mainCount ) { delete[] butterflyimg; butterflyimg = 0; delete[] logoimg; logoimg = 0; } } void Main::newView() { // Open a new view... have it delete when closed. Main *m = new Main(canvas, 0, 0, Qt::WDestructiveClose); m->show(); } void Main::clear() { editor->clear(); } void Main::help() { static QMessageBox* about = new QMessageBox( "Qt Canvas Example", "<h3>The QCanvas classes example</h3>" "<ul>" "<li> Press ALT-S for some sprites." "<li> Press ALT-C for some circles." "<li> Press ALT-L for some lines." "<li> Drag the objects around." "<li> Read the code!" "</ul>", QMessageBox::Information, 1, 0, 0, this, 0, FALSE ); about->setButtonText( 1, "Dismiss" ); about->show(); } void Main::aboutQt() { QMessageBox::aboutQt( this, "Qt Canvas Example" ); } void Main::enlarge() { canvas.setSceneRect(0, 0, canvas.width()*4/3, canvas.height()*4/3); } void Main::shrink() { canvas.setSceneRect(0, 0, qMax(canvas.width()*3/4, qreal(1.0)), qMax(canvas.height()*3/4, qreal(1.0))); } void Main::rotateClockwise() { editor->rotate( 22.5 ); } void Main::rotateCounterClockwise() { editor->rotate( -22.5 ); } void Main::zoomIn() { editor->scale( 2.0, 2.0 ); } void Main::zoomOut() { editor->scale( 0.5, 0.5 ); } void Main::mirror() { editor->scale( -1, 1 ); } void Main::moveL() { editor->translate( -16, 0 ); } void Main::moveR() { editor->translate( +16, 0 ); } void Main::moveU() { editor->translate( 0, -16 ); } void Main::moveD() { editor->translate( 0, +16 ); } void Main::print() { if ( !printer ) printer = new QPrinter; if ( printer->setup(this) ) { QPainter pp(printer); canvas.render(&pp); } } void Main::addSprite() { BouncyLogo* i = new BouncyLogo; canvas.addItem(i); i->initPos(); i->setZValue(qrand()%256); } QString butterfly_fn; QString logo_fn; void Main::addButterfly() { if ( butterfly_fn.isEmpty() ) return; if ( !butterflyimg ) { butterflyimg = new QImage[4]; butterflyimg[0].load( butterfly_fn ); butterflyimg[1] = butterflyimg[0].smoothScale( int(butterflyimg[0].width()*0.75), int(butterflyimg[0].height()*0.75) ); butterflyimg[2] = butterflyimg[0].smoothScale( int(butterflyimg[0].width()*0.5), int(butterflyimg[0].height()*0.5) ); butterflyimg[3] = butterflyimg[0].smoothScale( int(butterflyimg[0].width()*0.25), int(butterflyimg[0].height()*0.25) ); } QAbstractGraphicsShapeItem* i = new ImageItem(butterflyimg[qrand()%4]); canvas.addItem(i); i->setPos(qrand()%int(canvas.width()-butterflyimg->width()), qrand()%int(canvas.height()-butterflyimg->height())); i->setZValue(qrand()%256+250); } void Main::addLogo() { if ( logo_fn.isEmpty() ) return; if ( !logoimg ) { logoimg = new QImage[4]; logoimg[0].load( logo_fn ); logoimg[1] = logoimg[0].smoothScale( int(logoimg[0].width()*0.75), int(logoimg[0].height()*0.75) ); logoimg[2] = logoimg[0].smoothScale( int(logoimg[0].width()*0.5), int(logoimg[0].height()*0.5) ); logoimg[3] = logoimg[0].smoothScale( int(logoimg[0].width()*0.25), int(logoimg[0].height()*0.25) ); } QAbstractGraphicsShapeItem* i = new ImageItem(logoimg[qrand()%4]); canvas.addItem(i); i->setPos(qrand()%int(canvas.width()-logoimg->width()), qrand()%int(canvas.height()-logoimg->width())); i->setZValue(qrand()%256+256); } void Main::addCircle() { QAbstractGraphicsShapeItem* i = canvas.addEllipse(QRectF(0,0,50,50)); i->setFlag(QGraphicsItem::ItemIsMovable); i->setPen(Qt::NoPen); i->setBrush( QColor(qrand()%32*8,qrand()%32*8,qrand()%32*8) ); i->setPos(qrand()%int(canvas.width()),qrand()%int(canvas.height())); i->setZValue(qrand()%256); } void Main::addHexagon() { const int size = int(canvas.width() / 25); Q3PointArray pa(6); pa[0] = QPoint(2*size,0); pa[1] = QPoint(size,-size*173/100); pa[2] = QPoint(-size,-size*173/100); pa[3] = QPoint(-2*size,0); pa[4] = QPoint(-size,size*173/100); pa[5] = QPoint(size,size*173/100); QGraphicsPolygonItem* i = canvas.addPolygon(pa); i->setFlag(QGraphicsItem::ItemIsMovable); i->setPen(Qt::NoPen); i->setBrush( QColor(qrand()%32*8,qrand()%32*8,qrand()%32*8) ); i->setPos(qrand()%int(canvas.width()),qrand()%int(canvas.height())); i->setZValue(qrand()%256); } void Main::addPolygon() { const int size = int(canvas.width()/2); Q3PointArray pa(6); pa[0] = QPoint(0,0); pa[1] = QPoint(size,size/5); pa[2] = QPoint(size*4/5,size); pa[3] = QPoint(size/6,size*5/4); pa[4] = QPoint(size*3/4,size*3/4); pa[5] = QPoint(size*3/4,size/4); QGraphicsPolygonItem* i = canvas.addPolygon(pa); i->setFlag(QGraphicsItem::ItemIsMovable); i->setPen(Qt::NoPen); i->setBrush( QColor(qrand()%32*8,qrand()%32*8,qrand()%32*8) ); i->setPos(qrand()%int(canvas.width()),qrand()%int(canvas.height())); i->setZValue(qrand()%256); } void Main::addSpline() { const int size = int(canvas.width()/6); Q3PointArray pa(12); pa[0] = QPoint(0,0); pa[1] = QPoint(size/2,0); pa[2] = QPoint(size,size/2); pa[3] = QPoint(size,size); pa[4] = QPoint(size,size*3/2); pa[5] = QPoint(size/2,size*2); pa[6] = QPoint(0,size*2); pa[7] = QPoint(-size/2,size*2); pa[8] = QPoint(size/4,size*3/2); pa[9] = QPoint(0,size); pa[10]= QPoint(-size/4,size/2); pa[11]= QPoint(-size/2,0); QPainterPath path; path.moveTo(pa[0]); for (int i = 1; i < pa.size(); i += 3) path.cubicTo(pa[i], pa[(i + 1) % pa.size()], pa[(i + 2) % pa.size()]); QGraphicsPathItem* item = canvas.addPath(path); item->setFlag(QGraphicsItem::ItemIsMovable); item->setPen(Qt::NoPen); item->setBrush( QColor(qrand()%32*8,qrand()%32*8,qrand()%32*8) ); item->setPos(qrand()%int(canvas.width()),qrand()%int(canvas.height())); item->setZValue(qrand()%256); } void Main::addText() { QGraphicsTextItem* i = canvas.addText("QCanvasText"); i->setFlag(QGraphicsItem::ItemIsMovable); i->setPos(qrand()%int(canvas.width()),qrand()%int(canvas.height())); i->setZValue(qrand()%256); } void Main::addLine() { QGraphicsLineItem* i = canvas.addLine(QLineF( qrand()%int(canvas.width()), qrand()%int(canvas.height()), qrand()%int(canvas.width()), qrand()%int(canvas.height()) )); i->setFlag(QGraphicsItem::ItemIsMovable); i->setPen( QPen(QColor(qrand()%32*8,qrand()%32*8,qrand()%32*8), 6) ); i->setZValue(qrand()%256); } void Main::addMesh() { int x0 = 0; int y0 = 0; if ( !tb ) tb = new QBrush( Qt::red ); if ( !tp ) tp = new QPen( Qt::black ); int nodecount = 0; int w = int(canvas.width()); int h = int(canvas.height()); const int dist = 30; int rows = h / dist; int cols = w / dist; #ifndef QT_NO_PROGRESSDIALOG Q3ProgressDialog progress( "Creating mesh...", "Abort", rows, this, "progress", TRUE ); #endif Q3MemArray<NodeItem*> lastRow(cols); for ( int j = 0; j < rows; j++ ) { int n = j%2 ? cols-1 : cols; NodeItem *prev = 0; for ( int i = 0; i < n; i++ ) { NodeItem *el = new NodeItem; canvas.addItem(el); nodecount++; int r = qrand(); int xrand = r %20; int yrand = (r/20) %20; el->setPos( xrand + x0 + i*dist + (j%2 ? dist/2 : 0 ), yrand + y0 + j*dist ); if ( j > 0 ) { if ( i < cols-1 ) canvas.addItem(new EdgeItem( lastRow[i], el)); if ( j%2 ) canvas.addItem(new EdgeItem( lastRow[i+1], el)); else if ( i > 0 ) canvas.addItem(new EdgeItem( lastRow[i-1], el)); } if ( prev ) { canvas.addItem(new EdgeItem( prev, el)); } if ( i > 0 ) lastRow[i-1] = prev; prev = el; } lastRow[n-1]=prev; #ifndef QT_NO_PROGRESSDIALOG progress.setProgress( j ); if ( progress.wasCancelled() ) break; #endif } #ifndef QT_NO_PROGRESSDIALOG progress.setProgress( rows ); #endif // qDebug( "%d nodes, %d edges", nodecount, EdgeItem::count() ); } void Main::addRectangle() { QAbstractGraphicsShapeItem *i = canvas.addRect( QRectF(qrand()%int(canvas.width()), qrand()%int(canvas.height()), canvas.width()/5, canvas.width()/5) ); i->setFlag(QGraphicsItem::ItemIsMovable); int z = qrand()%256; i->setBrush( QColor(z,z,z) ); i->setPen( QPen(QColor(qrand()%32*8,qrand()%32*8,qrand()%32*8), 6) ); i->setZValue(z); }
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