/****************************************************************************

** 

**

** Copyright (C) 1992-1998 Troll Tech AS.  All rights reserved.

**

** This file is part of an example program for Qt.  This example

** program may be used, distributed and modified without limitation.

**

*****************************************************************************/

#include "hello.h"

#include <qpushbutton.h>

#include <qtimer.h>

#include <qpainter.h>

#include <qpixmap.h>

/*

  Constructs a Hello widget. Starts a 40 ms animation timer.

*/

Hello::Hello( const char *text, QWidget *parent, const char *name )

    : QWidget(parent,name), t(text), b(0)

{

    QTimer *timer = new QTimer(this);

    connect( timer, SIGNAL(timeout()), SLOT(animate()) );

    timer->start( 40 );

    resize( 200, 100 );

}

/*

  This private slot is called each time the timer fires.

*/

void Hello::animate()

{

    b = (b + 1) & 15;

    repaint( FALSE );

}

/*

  Handles mouse button release events for the Hello widget.

  We emit the clicked() signal when the mouse is released inside

  the widget.

*/

void Hello::mouseReleaseEvent( QMouseEvent *e )

{

    if ( rect().contains( e->pos() ) )

	emit clicked();

}

/*

  Handles paint events for the Hello widget.

  Flicker-free update. The text is first drawn in the pixmap and the

  pixmap is then blt'ed to the screen.

*/

void Hello::paintEvent( QPaintEvent * )

{

    static int sin_tbl[16] = {

	0, 38, 71, 92, 100, 92, 71, 38,	0, -38, -71, -92, -100, -92, -71, -38};

    if ( t.isEmpty() )

	return;

    // 1: Compute some sizes, positions etc.

    QFontMetrics fm = fontMetrics();

    int w = fm.width(t) + 20;

    int h = fm.height() * 2;

    int pmx = width()/2 - w/2;

    int pmy = height()/2 - h/2;

    // 2: Create the pixmap and fill it with the widget's background

    QPixmap pm( w, h );

    pm.fill( this, pmx, pmy );

    // 3: Paint the pixmap. Cool wave effect

    QPainter p;

    int x = 10;

    int y = h/2 + fm.descent();

    int i = 0;

    p.begin( &pm );

    p.setFont( font() );

    while ( t[i] ) {

	int i16 = (b+i) & 15;

        p.setPen( QColor((15-i16)*16,255,255,QColor::Hsv) );

	p.drawText( x, y-sin_tbl[i16]*h/800, &t[i], 1 );

	x += fm.width( t[i] );

	i++;

    }

    p.end();

    // 4: Copy the pixmap to the Hello widget

    bitBlt( this, pmx, pmy, &pm );

}