chassiscircular2.cpp

/***************************************************************************
 *   Copyright (C) 2005 by David Saxton                                    *
 *   david@bluehaze.org                                                    *
 *                                                                         *
 *   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.                                   *
 ***************************************************************************/

#include "chassiscircular2.h"

#include "libraryitem.h"

#include <klocale.h>
#include <qpainter.h>
#include <qwmatrix.h>

#include <algorithm>
#include <cmath>

double normalizeAngle( double angle );


Item* ChassisCircular2::construct( ItemDocument *itemDocument, bool newItem, const char *id )
{
        return new ChassisCircular2( (MechanicsDocument*)itemDocument, newItem, id );
}


LibraryItem* ChassisCircular2::libraryItem()
{
        return new LibraryItem(
                QString("mech/chassis_circular_2"),
                i18n("Circular 2-Wheel Chassis"),
                i18n("Chassis'"),
                "chassis.png",
                LibraryItem::lit_mechanical,
                ChassisCircular2::construct );
}


ChassisCircular2::ChassisCircular2( MechanicsDocument *mechanicsDocument, bool newItem, const char *id )
        : MechanicsItem( mechanicsDocument, newItem, (id) ? id : "chassis_circular_2" )
{
        m_name = i18n("Circular 2-Wheel Chassis");
        m_desc = i18n("A circular base with two wheels and a support point.");
        
        m_theta1 = 0.0;
        m_theta2 = 0.0;
        
        QPointArray pa;
        pa.makeEllipse( -25, -25, 50, 50 );
        QWMatrix m(4,0,0,4,0,0);
        m.setTransformationMode( QWMatrix::Areas );
        pa = m.map(pa);
        setItemPoints(pa);
        
        itemResized();
}


ChassisCircular2::~ChassisCircular2()
{
}


void ChassisCircular2::itemResized()
{
        const double w = sizeRect().width();
        const double h = sizeRect().height();
        
        m_wheel1Pos = QRect( int(w/5), int(h/6), int(w/4), int(h/8) );
        m_wheel2Pos = QRect( int(w/5), int(5*h/6-h/8), int(w/4), int(h/8) );
}


void ChassisCircular2::advance( int phase )
{
        if ( phase != 1 )
                return;
        
        double speed1 = 60.; // pixels per second
        double speed2 = 160.; // pixels per second
        
        m_theta1 = normalizeAngle( m_theta1 + (speed1/1000.)/m_wheel1Pos.width() );
        m_theta2 = normalizeAngle( m_theta2 + (speed2/1000.)/m_wheel2Pos.width() );
        
        const double d1 = speed1/1000.;
        const double d2 = speed2/1000.;
        const double sep = m_wheel2Pos.center().y()-m_wheel1Pos.center().y();
        
        double dtheta = std::atan( (d2-d1)/sep ); // Change in orientation of chassis
        double moveAngle = absolutePosition().angle()+dtheta/2;
        rotateBy(dtheta);
        moveBy( ((d1+d2)/2.)*std::cos(moveAngle), ((d1+d2)/2.)*std::sin(moveAngle) );
}


void ChassisCircular2::drawShape( QPainter &p )
{
        const double _x = int(sizeRect().x() + x());
        const double _y = int(sizeRect().y() + y());
        const double w = sizeRect().width();
        const double h = sizeRect().height(); 
        
        initPainter(p);
        p.setBrush( QColor( 255, 246, 210 ) );
        QRect circleRect = sizeRect();
        circleRect.moveLeft( int(circleRect.left() + x()) );
        circleRect.moveTop( int(circleRect.top() + y()) );
        p.drawEllipse(circleRect);
        
        // Draw wheels
        // TODO get this info from m_wheel1Pos and m_wheel2Pos
        const double X = _x+(w/5); // Wheel's left pos
        const double H = h/8; // Wheel's height
        const double y1 = _y+(h/6); // Wheel 1 y-pos
        const double y2 = _y+(5*h/6)-H; // Wheel 2 y-pos
        
        p.setPen( Qt::NoPen );
        const double stripeWidth = 5;
        const double offset2 = 1 + int(m_theta1*m_wheel1Pos.width())%int(2*stripeWidth);
        const double offset1 = 1 + int(m_theta2*m_wheel2Pos.width())%int(2*stripeWidth);
        p.setBrush( QColor( 255, 232, 182 ) );
        for ( double i=-1; i<std::ceil(m_wheel1Pos.width()/stripeWidth); ++i )
        {
                
                p.setClipRect( QRect( int(_x+m_wheel1Pos.x()+2), int(_y+m_wheel1Pos.y()+2), int(m_wheel1Pos.width()-4), int(m_wheel1Pos.height()-4) ), QPainter::CoordPainter );
                p.drawRect( int(offset1+X + i*stripeWidth*2), int(y1+1), int(stripeWidth), int(H-2) );
                
                p.setClipRect( QRect( int(_x+m_wheel2Pos.x()+2), int(_y+m_wheel2Pos.y()+2), int(m_wheel2Pos.width()-4), int(m_wheel2Pos.height()-4) ), QPainter::CoordPainter );
                p.drawRect( int(offset2+X + i*stripeWidth*2), int(y2+1), int(stripeWidth), int(H-2) );
        }
        p.setClipping(false);
        
        p.setPen( Qt::black );
        p.setBrush( Qt::NoBrush );
        p.drawRoundRect( int(X), int(y1), int(w/4), int(H), 25, 50 );
        p.drawRoundRect( int(X), int(y2), int(w/4), int(H), 25, 50 );
        
        
        deinitPainter(p);
}

---