canvas-example.html

QT 下载资料仅供参考

    <a href="qcanvasitemlist.html">QCanvasItemList</a> list = <a href="qcanvasitem.html#canvas">canvas</a>()-&gt;allItems();
    QCanvasItemList::Iterator it = list.<a href="qvaluelist.html#begin">begin</a>();
    for (; it != list.<a href="qvaluelist.html#end">end</a>(); ++it) {
        if ( *it )
            delete *it;
    }
}

<a name="x2726"></a>void FigureEditor::<a href="qscrollview.html#contentsMouseMoveEvent">contentsMouseMoveEvent</a>(QMouseEvent* e)
{
    if ( moving ) {
        <a href="qpoint.html">QPoint</a> p = inverseWorldMatrix().map(e-&gt;pos());
        moving-&gt;moveBy(p.<a href="qpoint.html#x">x</a>() - moving_start.x(),
                       p.<a href="qpoint.html#y">y</a>() - moving_start.y());
        moving_start = p;
        <a href="qcanvasitem.html#canvas">canvas</a>()-&gt;update();
    }
}



<a name="f587"></a>BouncyLogo::BouncyLogo(QCanvas* canvas) :
    <a href="qcanvassprite.html">QCanvasSprite</a>(0,canvas)
{
    static QCanvasPixmapArray logo("qt-trans.xpm");
    <a href="qcanvassprite.html#setSequence">setSequence</a>(&amp;logo);
    <a href="qcanvasitem.html#setAnimated">setAnimated</a>(TRUE);
    initPos();
}


const int logo_rtti = 1234;

<a name="x2704"></a>int BouncyLogo::<a href="qcanvassprite.html#rtti">rtti</a>() const
{
    return logo_rtti;
}

void <a name="f588"></a>BouncyLogo::initPos()
{
    initSpeed();
    int trial=1000;
    do {
        <a href="qcanvassprite.html#move">move</a>(rand()%canvas()-&gt;width(),rand()%canvas()-&gt;height());
        advance(0);
    } while (trial-- &amp;&amp; xVelocity()==0.0 &amp;&amp; yVelocity()==0.0);
}

void <a name="f589"></a>BouncyLogo::initSpeed()
{
    const double speed = 4.0;
    double d = (double)(rand()%1024) / 1024.0;
    setVelocity( d*speed*2-speed, (1-d)*speed*2-speed );
}

<a name="x2703"></a>void BouncyLogo::<a href="qcanvassprite.html#advance">advance</a>(int stage)
{
    switch ( stage ) {
      case 0: {
        double vx = xVelocity();
        double vy = yVelocity();

        if ( vx == 0.0 &amp;&amp; vy == 0.0 ) {
            // stopped last turn
            initSpeed();
            vx = xVelocity();
            vy = yVelocity();
        }

        double nx = <a href="qwidget.html#x">x</a>() + vx;
        double ny = <a href="qwidget.html#y">y</a>() + vy;

        if ( nx &lt; 0 || nx &gt;= canvas()-&gt;width() )
            vx = -vx;
        if ( ny &lt; 0 || ny &gt;= canvas()-&gt;height() )
            vy = -vy;

        for (int bounce=0; bounce&lt;4; bounce++) {
            <a href="qcanvasitemlist.html">QCanvasItemList</a> l=collisions(FALSE);
            for (QCanvasItemList::Iterator it=l.<a href="qvaluelist.html#begin">begin</a>(); it!=l.<a href="qvaluelist.html#end">end</a>(); ++it) {
                <a href="qcanvasitem.html">QCanvasItem</a> *hit = *it;
<a name="x2693"></a><a name="x2690"></a>                if ( hit-&gt;<a href="qcanvasitem.html#rtti">rtti</a>()==logo_rtti &amp;&amp; hit-&gt;<a href="qcanvasitem.html#collidesWith">collidesWith</a>(this) ) {
                    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;
                    }
                    setVelocity(vx,vy);
                    break;
                }
            }
        }

        if ( <a href="qwidget.html#x">x</a>()+vx &lt; 0 || x()+vx &gt;= canvas()-&gt;width() )
            vx = 0;
        if ( <a href="qwidget.html#y">y</a>()+vy &lt; 0 || y()+vy &gt;= canvas()-&gt;height() )
            vy = 0;

        setVelocity(vx,vy);
      } break;
      case 1:
<a name="x2689"></a>        <a href="qcanvasitem.html">QCanvasItem</a>::<a href="qcanvasitem.html#advance">advance</a>(stage);
        break;
    }
}

static uint mainCount = 0;
static QImage *butterflyimg;
static QImage *logoimg;

<a name="f597"></a>Main::Main(QCanvas&amp; c, QWidget* parent, const char* name, WFlags f) :
    <a href="qmainwindow.html">QMainWindow</a>(parent,name,f),
    canvas(c)
{
    editor = new FigureEditor(canvas,this);
    <a href="qmenubar.html">QMenuBar</a>* menu = <a href="qmainwindow.html#menuBar">menuBar</a>();

    <a href="qpopupmenu.html">QPopupMenu</a>* file = new <a href="qpopupmenu.html">QPopupMenu</a>( menu );
<a name="x2712"></a>    file-&gt;<a href="qmenudata.html#insertItem">insertItem</a>("&amp;Fill canvas", this, SLOT(init()), CTRL+Key_F);
    file-&gt;<a href="qmenudata.html#insertItem">insertItem</a>("&amp;Erase canvas", this, SLOT(clear()), CTRL+Key_E);
    file-&gt;<a href="qmenudata.html#insertItem">insertItem</a>("&amp;New view", this, SLOT(newView()), CTRL+Key_N);
    file-&gt;<a href="qmenudata.html#insertSeparator">insertSeparator</a>();
    file-&gt;<a href="qmenudata.html#insertItem">insertItem</a>("&amp;Print", this, SLOT(print()), CTRL+Key_P);
    file-&gt;<a href="qmenudata.html#insertSeparator">insertSeparator</a>();
    file-&gt;<a href="qmenudata.html#insertItem">insertItem</a>("E&amp;xit", qApp, SLOT(<a href="qapplication.html#quit">quit</a>()), CTRL+Key_Q);
    menu-&gt;<a href="qmenudata.html#insertItem">insertItem</a>("&amp;File", file);

    <a href="qpopupmenu.html">QPopupMenu</a>* edit = new <a href="qpopupmenu.html">QPopupMenu</a>( menu );
    edit-&gt;<a href="qmenudata.html#insertItem">insertItem</a>("Add &amp;Circle", this, SLOT(addCircle()), ALT+Key_C);
    edit-&gt;<a href="qmenudata.html#insertItem">insertItem</a>("Add &amp;Hexagon", this, SLOT(addHexagon()), ALT+Key_H);
    edit-&gt;<a href="qmenudata.html#insertItem">insertItem</a>("Add &amp;Polygon", this, SLOT(addPolygon()), ALT+Key_P);
    edit-&gt;<a href="qmenudata.html#insertItem">insertItem</a>("Add Spl&amp;ine", this, SLOT(addSpline()), ALT+Key_I);
    edit-&gt;<a href="qmenudata.html#insertItem">insertItem</a>("Add &amp;Text", this, SLOT(addText()), ALT+Key_T);
    edit-&gt;<a href="qmenudata.html#insertItem">insertItem</a>("Add &amp;Line", this, SLOT(addLine()), ALT+Key_L);
    edit-&gt;<a href="qmenudata.html#insertItem">insertItem</a>("Add &amp;Rectangle", this, SLOT(addRectangle()), ALT+Key_R);
    edit-&gt;<a href="qmenudata.html#insertItem">insertItem</a>("Add &amp;Sprite", this, SLOT(addSprite()), ALT+Key_S);
    edit-&gt;<a href="qmenudata.html#insertItem">insertItem</a>("Create &amp;Mesh", this, SLOT(addMesh()), ALT+Key_M );
    edit-&gt;<a href="qmenudata.html#insertItem">insertItem</a>("Add &amp;Alpha-blended image", this, SLOT(addButterfly()), ALT+Key_A);
    menu-&gt;<a href="qmenudata.html#insertItem">insertItem</a>("&amp;Edit", edit);

    <a href="qpopupmenu.html">QPopupMenu</a>* view = new <a href="qpopupmenu.html">QPopupMenu</a>( menu );
    view-&gt;<a href="qmenudata.html#insertItem">insertItem</a>("&amp;Enlarge", this, SLOT(enlarge()), SHIFT+CTRL+Key_Plus);
    view-&gt;<a href="qmenudata.html#insertItem">insertItem</a>("Shr&amp;ink", this, SLOT(shrink()), SHIFT+CTRL+Key_Minus);
    view-&gt;<a href="qmenudata.html#insertSeparator">insertSeparator</a>();
    view-&gt;<a href="qmenudata.html#insertItem">insertItem</a>("&amp;Rotate clockwise", this, SLOT(rotateClockwise()), CTRL+Key_PageDown);
    view-&gt;<a href="qmenudata.html#insertItem">insertItem</a>("Rotate &amp;counterclockwise", this, SLOT(rotateCounterClockwise()), CTRL+Key_PageUp);
    view-&gt;<a href="qmenudata.html#insertItem">insertItem</a>("&amp;Zoom in", this, SLOT(zoomIn()), CTRL+Key_Plus);
    view-&gt;<a href="qmenudata.html#insertItem">insertItem</a>("Zoom &amp;out", this, SLOT(zoomOut()), CTRL+Key_Minus);
    view-&gt;<a href="qmenudata.html#insertItem">insertItem</a>("Translate left", this, SLOT(moveL()), CTRL+Key_Left);
    view-&gt;<a href="qmenudata.html#insertItem">insertItem</a>("Translate right", this, SLOT(moveR()), CTRL+Key_Right);
    view-&gt;<a href="qmenudata.html#insertItem">insertItem</a>("Translate up", this, SLOT(moveU()), CTRL+Key_Up);
    view-&gt;<a href="qmenudata.html#insertItem">insertItem</a>("Translate down", this, SLOT(moveD()), CTRL+Key_Down);
    view-&gt;<a href="qmenudata.html#insertItem">insertItem</a>("&amp;Mirror", this, SLOT(mirror()), CTRL+Key_Home);
    menu-&gt;<a href="qmenudata.html#insertItem">insertItem</a>("&amp;View", view);

    options = new <a href="qpopupmenu.html">QPopupMenu</a>( menu );
    dbf_id = options-&gt;<a href="qmenudata.html#insertItem">insertItem</a>("Double buffer", this, SLOT(toggleDoubleBuffer()));
<a name="x2715"></a>    options-&gt;<a href="qmenudata.html#setItemChecked">setItemChecked</a>(dbf_id, TRUE);
    menu-&gt;<a href="qmenudata.html#insertItem">insertItem</a>("&amp;Options",options);

    menu-&gt;<a href="qmenudata.html#insertSeparator">insertSeparator</a>();

    <a href="qpopupmenu.html">QPopupMenu</a>* help = new <a href="qpopupmenu.html">QPopupMenu</a>( menu );
    help-&gt;<a href="qmenudata.html#insertItem">insertItem</a>("&amp;About", this, SLOT(help()), Key_F1);
    help-&gt;<a href="qmenudata.html#setItemChecked">setItemChecked</a>(dbf_id, TRUE);
    menu-&gt;<a href="qmenudata.html#insertItem">insertItem</a>("&amp;Help",help);

    <a href="qmainwindow.html#statusBar">statusBar</a>();

    <a href="qmainwindow.html#setCentralWidget">setCentralWidget</a>(editor);

    printer = 0;

    init();
}

void <a name="f598"></a>Main::init()
{
    clear();

    static int r=24;
    srand(++r);

    mainCount++;
    butterflyimg = 0;
    logoimg = 0;

    int i;
<a name="x2688"></a>    for ( i=0; i&lt;canvas.<a href="qcanvas.html#width">width</a>() / 56; i++) {
        addButterfly();
    }
    for ( i=0; i&lt;canvas.<a href="qcanvas.html#width">width</a>() / 85; i++) {
        addHexagon();
    }
    for ( i=0; i&lt;canvas.<a href="qcanvas.html#width">width</a>() / 128; i++) {
        addLogo();
    }
}

Main::~Main()
{
    delete printer;
    if ( !--mainCount ) {
        delete[] butterflyimg;
        butterflyimg = 0;
        delete[] logoimg;
        logoimg = 0;
    }
}

void <a name="f599"></a>Main::newView()
{
    // Open a new view... have it delete when closed.
    Main *m = new Main(canvas, 0, 0, WDestructiveClose);
    qApp-&gt;<a href="qapplication.html#setMainWidget">setMainWidget</a>(m);
    m-&gt;<a href="qwidget.html#show">show</a>();
    qApp-&gt;<a href="qapplication.html#setMainWidget">setMainWidget</a>(0);
}

void <a name="f600"></a>Main::clear()
{
    editor-&gt;clear();
}

void <a name="f601"></a>Main::help()
{
    static QMessageBox* about = new <a href="qmessagebox.html">QMessageBox</a>( "Qt Canvas Example",
            "&lt;h3&gt;The QCanvas classes example&lt;/h3&gt;"
            "&lt;ul&gt;"
                "&lt;li&gt; Press ALT-S for some sprites."
                "&lt;li&gt; Press ALT-C for some circles."
                "&lt;li&gt; Press ALT-L for some lines."
                "&lt;li&gt; Drag the objects around."
                "&lt;li&gt; Read the code!"
            "&lt;/ul&gt;", QMessageBox::Information, 1, 0, 0, this, 0, FALSE );
    about-&gt;setButtonText( 1, "Dismiss" );
    about-&gt;show();
}

void <a name="f602"></a>Main::aboutQt()
{
    QMessageBox::<a href="qmessagebox.html#aboutQt">aboutQt</a>( this, "Qt Canvas Example" );
}

void <a name="f603"></a>Main::toggleDoubleBuffer()
{
<a name="x2714"></a>    bool s = !options-&gt;<a href="qmenudata.html#isItemChecked">isItemChecked</a>(dbf_id);
    options-&gt;<a href="qmenudata.html#setItemChecked">setItemChecked</a>(dbf_id,s);
<a name="x2687"></a>    canvas.<a href="qcanvas.html#setDoubleBuffering">setDoubleBuffering</a>(s);
}

void <a name="f604"></a>Main::enlarge()
{
<a name="x2686"></a><a name="x2685"></a>    canvas.<a href="qcanvas.html#resize">resize</a>(canvas.<a href="qcanvas.html#width">width</a>()*4/3, canvas.<a href="qcanvas.html#height">height</a>()*4/3);
}

void <a name="f605"></a>Main::shrink()
{
    canvas.<a href="qcanvas.html#resize">resize</a>(canvas.<a href="qcanvas.html#width">width</a>()*3/4, canvas.<a href="qcanvas.html#height">height</a>()*3/4);
}

void <a name="f606"></a>Main::rotateClockwise()
{
<a name="x2707"></a>    <a href="qwmatrix.html">QWMatrix</a> m = editor-&gt;<a href="qcanvasview.html#worldMatrix">worldMatrix</a>();
<a name="x2731"></a>    m.<a href="qwmatrix.html#rotate">rotate</a>( 22.5 );
<a name="x2706"></a>    editor-&gt;<a href="qcanvasview.html#setWorldMatrix">setWorldMatrix</a>( m );
}

void <a name="f607"></a>Main::rotateCounterClockwise()
{
    <a href="qwmatrix.html">QWMatrix</a> m = editor-&gt;<a href="qcanvasview.html#worldMatrix">worldMatrix</a>();
    m.<a href="qwmatrix.html#rotate">rotate</a>( -22.5 );
    editor-&gt;<a href="qcanvasview.html#setWorldMatrix">setWorldMatrix</a>( m );
}

void <a name="f608"></a>Main::zoomIn()
{
    <a href="qwmatrix.html">QWMatrix</a> m = editor-&gt;<a href="qcanvasview.html#worldMatrix">worldMatrix</a>();
<a name="x2732"></a>    m.<a href="qwmatrix.html#scale">scale</a>( 2.0, 2.0 );
    editor-&gt;<a href="qcanvasview.html#setWorldMatrix">setWorldMatrix</a>( m );
}

void <a name="f609"></a>Main::zoomOut()
{
    <a href="qwmatrix.html">QWMatrix</a> m = editor-&gt;<a href="qcanvasview.html#worldMatrix">worldMatrix</a>();
    m.<a href="qwmatrix.html#scale">scale</a>( 0.5, 0.5 );
    editor-&gt;<a href="qcanvasview.html#setWorldMatrix">setWorldMatrix</a>( m );
}

void <a name="f610"></a>Main::mirror()
{
    <a href="qwmatrix.html">QWMatrix</a> m = editor-&gt;<a href="qcanvasview.html#worldMatrix">worldMatrix</a>();
    m.<a href="qwmatrix.html#scale">scale</a>( -1, 1 );
    editor-&gt;<a href="qcanvasview.html#setWorldMatrix">setWorldMatrix</a>( m );
}

void <a name="f611"></a>Main::moveL()
{
    <a href="qwmatrix.html">QWMatrix</a> m = editor-&gt;<a href="qcanvasview.html#worldMatrix">worldMatrix</a>();
<a name="x2733"></a>    m.<a href="qwmatrix.html#translate">translate</a>( -16, 0 );
    editor-&gt;<a href="qcanvasview.html#setWorldMatrix">setWorldMatrix</a>( m );
}

void <a name="f612"></a>Main::moveR()
{
    <a href="qwmatrix.html">QWMatrix</a> m = editor-&gt;<a href="qcanvasview.html#worldMatrix">worldMatrix</a>();
    m.<a href="qwmatrix.html#translate">translate</a>( +16, 0 );
    editor-&gt;<a href="qcanvasview.html#setWorldMatrix">setWorldMatrix</a>( m );