Add Qt3 development HEAD version

1 files changed, 156 insertions, 0 deletions

diff --git a/tutorial/t11/cannon.cpp b/tutorial/t11/cannon.cpp
new file mode 100644
index 0000000..bf44a6d
--- /dev/null
+++ b/tutorial/t11/cannon.cpp
@@ -0,0 +1,156 @@
+/****************************************************************
+**
+** Implementation CannonField class, Qt tutorial 11
+**
+****************************************************************/
+
+#include "cannon.h"
+#include <qtimer.h>
+#include <qpainter.h>
+#include <qpixmap.h>
+
+#include <math.h>
+
+
+CannonField::CannonField( QWidget *parent, const char *name )
+        : QWidget( parent, name )
+{
+    ang = 45;
+    f = 0;
+    timerCount = 0;
+    autoShootTimer = new QTimer( this, "movement handler" );
+    connect( autoShootTimer, SIGNAL(timeout()),
+	     this, SLOT(moveShot()) );
+    shoot_ang = 0;
+    shoot_f = 0;
+    setPalette( QPalette( QColor( 250, 250, 200) ) );
+}
+
+
+void CannonField::setAngle( int degrees )
+{
+    if ( degrees < 5 )
+	degrees = 5;
+    if ( degrees > 70 )
+	degrees = 70;
+    if ( ang == degrees )
+	return;
+    ang = degrees;
+    repaint( cannonRect(), FALSE );
+    emit angleChanged( ang );
+}
+
+
+void CannonField::setForce( int newton )
+{
+    if ( newton < 0 )
+	newton = 0;
+    if ( f == newton )
+	return;
+    f = newton;
+    emit forceChanged( f );
+}
+
+
+void CannonField::shoot()
+{
+    if ( autoShootTimer->isActive() )
+	return;
+    timerCount = 0;
+    shoot_ang = ang;
+    shoot_f = f;
+    autoShootTimer->start( 50 );
+}
+
+
+void CannonField::moveShot()
+{
+    QRegion r( shotRect() );
+    timerCount++;
+
+    QRect shotR = shotRect();
+
+    if ( shotR.x() > width() || shotR.y() > height() )
+	autoShootTimer->stop();
+    else
+	r = r.unite( QRegion( shotR ) );
+    repaint( r );
+}
+
+
+void CannonField::paintEvent( QPaintEvent *e )
+{
+    QRect updateR = e->rect();
+    QPainter p( this );
+
+    if ( updateR.intersects( cannonRect() ) )
+	paintCannon( &p );
+    if ( autoShootTimer->isActive() &&
+	 updateR.intersects( shotRect() ) )
+	paintShot( &p );
+}
+
+
+void CannonField::paintShot( QPainter *p )
+{
+    p->setBrush( black );
+    p->setPen( NoPen );
+    p->drawRect( shotRect() );
+}
+
+
+const QRect barrelRect(33, -4, 15, 8);
+
+void CannonField::paintCannon( QPainter *p )
+{
+    QRect cr = cannonRect();
+    QPixmap pix( cr.size() );
+    pix.fill( this, cr.topLeft() );
+
+    QPainter tmp( &pix );
+    tmp.setBrush( blue );
+    tmp.setPen( NoPen );
+
+    tmp.translate( 0, pix.height() - 1 );
+    tmp.drawPie( QRect( -35,-35, 70, 70 ), 0, 90*16 );
+    tmp.rotate( -ang );
+    tmp.drawRect( barrelRect );
+    tmp.end();
+
+    p->drawPixmap( cr.topLeft(), pix );
+}
+
+
+QRect CannonField::cannonRect() const
+{
+    QRect r( 0, 0, 50, 50 );
+    r.moveBottomLeft( rect().bottomLeft() );
+    return r;
+}
+
+
+QRect CannonField::shotRect() const
+{
+    const double gravity = 4;
+
+    double time      = timerCount / 4.0;
+    double velocity  = shoot_f;
+    double radians   = shoot_ang*3.14159265/180;
+
+    double velx      = velocity*cos( radians );
+    double vely      = velocity*sin( radians );
+    double x0        = ( barrelRect.right()  + 5 )*cos(radians);
+    double y0        = ( barrelRect.right()  + 5 )*sin(radians);
+    double x         = x0 + velx*time;
+    double y         = y0 + vely*time - 0.5*gravity*time*time;
+
+    QRect r = QRect( 0, 0, 6, 6 );
+    r.moveCenter( QPoint( qRound(x), height() - 1 - qRound(y) ) );
+    return r;
+}
+
+
+QSizePolicy CannonField::sizePolicy() const
+{
+    return QSizePolicy( QSizePolicy::Expanding, QSizePolicy::Expanding );
+}