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<pre>/****************************************************************
**
** Implementation CannonField class, TQt tutorial 11
**
****************************************************************/
#include "cannon.h"
#include <<a href="qtimer-h.html">ntqtimer.h</a>>
#include <<a href="qpainter-h.html">ntqpainter.h</a>>
#include <<a href="qpixmap-h.html">ntqpixmap.h</a>>
#include <math.h>
<a name="f57"></a>CannonField::CannonField( <a href="ntqwidget.html">TQWidget</a> *parent, const char *name )
: <a href="ntqwidget.html">TQWidget</a>( parent, name )
{
ang = 45;
f = 0;
timerCount = 0;
autoShootTimer = new <a href="ntqtimer.html">TQTimer</a>( this, "movement handler" );
<a href="ntqobject.html#connect">connect</a>( autoShootTimer, SIGNAL(<a href="ntqtimer.html#timeout">timeout</a>()),
this, SLOT(moveShot()) );
shoot_ang = 0;
shoot_f = 0;
<a href="ntqwidget.html#setPalette">setPalette</a>( TQPalette( TQColor( 250, 250, 200) ) );
}
void <a name="f58"></a>CannonField::setAngle( int degrees )
{
if ( degrees < 5 )
degrees = 5;
if ( degrees > 70 )
degrees = 70;
if ( ang == degrees )
return;
ang = degrees;
<a href="ntqwidget.html#repaint">repaint</a>( cannonRect(), FALSE );
emit angleChanged( ang );
}
void <a name="f59"></a>CannonField::setForce( int newton )
{
if ( newton < 0 )
newton = 0;
if ( f == newton )
return;
f = newton;
emit forceChanged( f );
}
void <a name="f60"></a>CannonField::shoot()
{
if ( autoShootTimer-><a href="ntqtimer.html#isActive">isActive</a>() )
return;
timerCount = 0;
shoot_ang = ang;
shoot_f = f;
autoShootTimer-><a href="ntqtimer.html#start">start</a>( 50 );
}
void <a name="f61"></a>CannonField::moveShot()
{
<a href="ntqregion.html">TQRegion</a> r( shotRect() );
timerCount++;
<a href="ntqrect.html">TQRect</a> shotR = shotRect();
if ( shotR.<a href="ntqrect.html#x">x</a>() > width() || shotR.<a href="ntqrect.html#y">y</a>() > height() )
autoShootTimer-><a href="ntqtimer.html#stop">stop</a>();
else
r = r.<a href="ntqrect.html#unite">unite</a>( TQRegion( shotR ) );
<a href="ntqwidget.html#repaint">repaint</a>( r );
}
void CannonField::<a href="ntqwidget.html#paintEvent">paintEvent</a>( <a href="qpaintevent.html">TQPaintEvent</a> *e )
{
<a href="ntqrect.html">TQRect</a> updateR = e-><a href="qpaintevent.html#rect">rect</a>();
<a href="ntqpainter.html">TQPainter</a> p( this );
if ( updateR.<a href="ntqrect.html#intersects">intersects</a>( cannonRect() ) )
paintCannon( &p );
if ( autoShootTimer-><a href="ntqtimer.html#isActive">isActive</a>() &&
updateR.<a href="ntqrect.html#intersects">intersects</a>( shotRect() ) )
paintShot( &p );
}
void <a name="f62"></a>CannonField::paintShot( <a href="ntqpainter.html">TQPainter</a> *p )
{
p-><a href="ntqpainter.html#setBrush">setBrush</a>( black );
p-><a href="ntqpainter.html#setPen">setPen</a>( NoPen );
p-><a href="ntqpainter.html#drawRect">drawRect</a>( shotRect() );
}
const <a href="ntqrect.html">TQRect</a> barrelRect(33, -4, 15, 8);
void <a name="f63"></a>CannonField::paintCannon( <a href="ntqpainter.html">TQPainter</a> *p )
{
<a href="ntqrect.html">TQRect</a> cr = cannonRect();
<a href="ntqpixmap.html">TQPixmap</a> pix( cr.<a href="ntqrect.html#size">size</a>() );
pix.<a href="ntqpixmap.html#fill">fill</a>( this, cr.<a href="ntqrect.html#topLeft">topLeft</a>() );
<a href="ntqpainter.html">TQPainter</a> tmp( &pix );
tmp.<a href="ntqpainter.html#setBrush">setBrush</a>( blue );
tmp.<a href="ntqpainter.html#setPen">setPen</a>( NoPen );
tmp.<a href="ntqpainter.html#translate">translate</a>( 0, pix.<a href="ntqpixmap.html#height">height</a>() - 1 );
tmp.<a href="ntqpainter.html#drawPie">drawPie</a>( TQRect( -35,-35, 70, 70 ), 0, 90*16 );
tmp.<a href="ntqpainter.html#rotate">rotate</a>( -ang );
tmp.<a href="ntqpainter.html#drawRect">drawRect</a>( barrelRect );
tmp.<a href="ntqpainter.html#end">end</a>();
p-><a href="ntqpainter.html#drawPixmap">drawPixmap</a>( cr.<a href="ntqrect.html#topLeft">topLeft</a>(), pix );
}
TQRect <a name="f64"></a>CannonField::cannonRect() const
{
<a href="ntqrect.html">TQRect</a> r( 0, 0, 50, 50 );
r.<a href="ntqrect.html#moveBottomLeft">moveBottomLeft</a>( <a href="ntqwidget.html#rect">rect</a>().bottomLeft() );
return r;
}
TQRect <a name="f65"></a>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.<a href="ntqrect.html#right">right</a>() + 5 )*cos(radians);
double y0 = ( barrelRect.<a href="ntqrect.html#right">right</a>() + 5 )*sin(radians);
double x = x0 + velx*time;
double y = y0 + vely*time - 0.5*gravity*time*time;
<a href="ntqrect.html">TQRect</a> r = TQRect( 0, 0, 6, 6 );
r.<a href="ntqrect.html#moveCenter">moveCenter</a>( TQPoint( tqRound(x), height() - 1 - tqRound(y) ) );
return r;
}
TQSizePolicy CannonField::<a href="ntqwidget.html#sizePolicy">sizePolicy</a>() const
{
return TQSizePolicy( TQSizePolicy::Expanding, TQSizePolicy::Expanding );
}
</pre><!-- eof -->
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