src/analog/led.cpp

/***************************************************************************
 *   Copyright (C) 2006-2008 by Tomasz Ziobrowski                          *
 *   http://www.3electrons.com                                             *
 *   e-mail: t.ziobrowski@3electrons.com                                   *
 *                                                                         *
 *                                                                         *
 *   This program is free software; you can redistribute it and/or modify  *
 *   it under the terms of the GNU General Public License as published by  *
 *   the Free Software Foundation; either version 2 of the License, or     *
 *   (at your option) any later version.                                   *
 *                                                                         *
 *   This program is distributed in the hope that it will be useful,       *
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
 *   GNU General Public License for more details.                          *
 *                                                                         *
 *   You should have received a copy of the GNU General Public License     *
 *   along with this program; if not, write to the                         *
 *   Free Software Foundation, Inc.,                                       *
 *   59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.             *
 ***************************************************************************/

#include <QtGui> 
#include "led.h" 


Led::Led(QWidget * parent):WidgetWithBackground(parent)
{
  m_checked = true; 
  m_color = Qt::red; 
  resize(330,330);      
}


bool Led::isChecked () const 
{
  return m_checked; 
}


void Led::setChecked(bool i) 
{
  m_checked = i; 
  updateWithBackground();
  checkChanged( m_checked ); 
}


QColor Led::color() const
{
  return m_color; 
}


void Led::setColor(QColor i)
{ 
  m_color = i; 
  updateWithBackground(); 
}

// Paints the whole diode - a circle with a base color, and a reflection over it
void Led::paintEvent(QPaintEvent * /* event*/ )
{
  QPainter painter(this); 
  initCoordinateSystem(painter); 
  // *** Draw circle
  int h,s,v,a; 
  QColor c,back = color(); 
  c=back; 
  
  // Color of the LED
  if (!m_checked || !isEnabled()) 
  { 
    back.getHsv(&h,&s,&v,&a);
    s *=0.70;
    a *=0.20;
    back.setHsv(h,s,v,a); 
  }
  painter.setBrush(back); 
  
  // LED circuit
  QPen pen;
  // rim darkening
  c.getHsv(&h,&s,&v,&a); 
  s*=0.5; 
  c.setHsv(h,s,v,a);  

  pen.setColor(c); 
  pen.setWidthF(3.0); 
    
  painter.drawEllipse(-149,-149,299,299);
  painter.end(); 
  
  // LED reflector
  drawBackground(); // It paints on what has been in the bitmap so far
}


// Draws a reflection of the light on the diode
void Led::paintBackground(QPainter & painter)
{
  initCoordinateSystem(painter); 
  painter.setPen(Qt::NoPen); 
  QRadialGradient shine(QPointF(-40.0,-40.0),120.0,QPointF(-40,-40));
  QColor white1(255,255,255,200);
  QColor white0(255,255,255,0);
  
  shine.setColorAt(0.0,white1); 
  shine.setColorAt(1.0,white0); 
  
  painter.setBrush(shine); 
  painter.drawEllipse(-147,-147,297,297); 
        
}

void Led::initCoordinateSystem(QPainter & painter)
{
  int side = qMin(width(), height());
  // painter initialization
  painter.setRenderHint(QPainter::Antialiasing);
  painter.translate(width() / 2, height() / 2);
  painter.scale(side / 330.0, side / 330.0);
}