vstar.cpp

/* This file is part of the KDE project
   Copyright (C) 2001, 2002, 2003 The Karbon Developers
 
   This library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Library General Public
   License as published by the Free Software Foundation; either
   version 2 of the License, or (at your option) any later version.
 
   This library 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
   Library General Public License for more details.
 
   You should have received a copy of the GNU Library General Public License
   along with this library; see the file COPYING.LIB.  If not, write to
   the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
 * Boston, MA 02110-1301, USA.
*/
 
 
#include <math.h>
 
#include <tqwmatrix.h>
#include <tqdom.h>
 
#include "vglobal.h"
#include "vstar.h"
#include "vtransformcmd.h"
#include <tdelocale.h>
#include <KoUnit.h>
#include <vdocument.h>
 
VStar::VStar( VObject* parent, VState state )
    : VPath( parent, state )
{
}
 
VStar::VStar( VObject* parent,
        const KoPoint& center, double outerRadius, double innerRadius,
        uint edges, double angle, uint innerAngle, double roundness, VStarType type )
    : VPath( parent ), m_center( center), m_outerRadius( outerRadius ), m_innerRadius( innerRadius), m_edges( edges ), m_angle( angle ), m_innerAngle( innerAngle ), m_roundness( roundness ), m_type( type )
{
    init();
}
 
void
VStar::init()
{
    double angle = m_angle;
 
    // A star should have at least 3 edges:
    if( m_edges < 3 )
        m_edges = 3;
 
    // Make sure, radii are positive:
    if( m_outerRadius < 0.0 )
        m_outerRadius = -m_outerRadius;
 
    if( m_innerRadius < 0.0 )
        m_innerRadius = -m_innerRadius;
 
    // trick for spoke, wheel (libart bug?)
    if( m_type == spoke || m_type == wheel && m_roundness == 0.0 )
        m_roundness = 0.01;
 
    // We start at angle + VGlobal::pi_2:
    KoPoint p2, p3;
    KoPoint p(
        m_outerRadius * cos( angle + VGlobal::pi_2 ),
        m_outerRadius * sin( angle + VGlobal::pi_2 ) );
    moveTo( p );
 
    double inAngle = VGlobal::twopi / 360 * m_innerAngle;
 
    if( m_type == star )
    {
        int j = ( m_edges % 2 == 0 ) ? ( m_edges - 2 ) / 2 : ( m_edges - 1 ) / 2;
        //innerRadius = getOptimalInnerRadius( outerRadius, edges, innerAngle );
        int jumpto = 0;
        bool discontinueous = ( m_edges % 4 == 2 );
 
        double outerRoundness = ( VGlobal::twopi * m_outerRadius * m_roundness ) / m_edges;
        double nextOuterAngle;
 
        for ( uint i = 1; i < m_edges + 1; ++i )
        {
            double nextInnerAngle = angle + inAngle + VGlobal::pi_2 + VGlobal::twopi / m_edges * ( jumpto + 0.5 );
            p.setX( m_innerRadius * cos( nextInnerAngle ) );
            p.setY( m_innerRadius * sin( nextInnerAngle ) );
            if( m_roundness == 0.0 )
                lineTo( p );
            else
            {
                nextOuterAngle = angle + VGlobal::pi_2 + VGlobal::twopi / m_edges * jumpto;
                p2.setX( m_outerRadius * cos( nextOuterAngle ) -
                    cos( angle + VGlobal::twopi / m_edges * jumpto ) * outerRoundness );
                p2.setY( m_outerRadius * sin( nextOuterAngle ) -
                    sin( angle + VGlobal::twopi / m_edges * jumpto ) * outerRoundness );
 
                curveTo( p2, p, p );
            }
 
            jumpto = ( i * j ) % m_edges;
            nextInnerAngle = angle + inAngle + VGlobal::pi_2 + VGlobal::twopi / m_edges * ( jumpto - 0.5 );
            p.setX( m_innerRadius * cos( nextInnerAngle ) );
            p.setY( m_innerRadius * sin( nextInnerAngle ) );
            lineTo( p );
 
            nextOuterAngle = angle + VGlobal::pi_2 + VGlobal::twopi / m_edges * jumpto;
            p.setX( m_outerRadius * cos( nextOuterAngle ) );
            p.setY( m_outerRadius * sin( nextOuterAngle ) );
 
            if( m_roundness == 0.0 )
                lineTo( p );
            else
            {
                p2.setX( m_innerRadius * cos( nextInnerAngle ) );
                p2.setY( m_innerRadius * sin( nextInnerAngle ) );
 
                p3.setX( m_outerRadius * cos( nextOuterAngle ) +
                    cos( angle + VGlobal::twopi / m_edges * jumpto ) * outerRoundness );
                p3.setY( m_outerRadius * sin( nextOuterAngle ) +
                    sin( angle + VGlobal::twopi / m_edges * jumpto ) * outerRoundness );
 
                curveTo( p2, p3, p );
            }
            if( discontinueous && i == ( m_edges / 2 ) )
            {
                angle += VGlobal::pi;
                nextOuterAngle = angle + VGlobal::pi_2 + VGlobal::twopi / m_edges * jumpto;
                p.setX( m_outerRadius * cos( nextOuterAngle ) );
                p.setY( m_outerRadius * sin( nextOuterAngle ) );
                moveTo( p );
            }
        }
    }
    else
    {
        if( m_type == wheel || m_type == spoke )
            m_innerRadius = 0.0;
 
        double innerRoundness = ( VGlobal::twopi * m_innerRadius * m_roundness ) / m_edges;
        double outerRoundness = ( VGlobal::twopi * m_outerRadius * m_roundness ) / m_edges;
 
        for ( uint i = 0; i < m_edges; ++i )
        {
            double nextOuterAngle = angle + VGlobal::pi_2 + VGlobal::twopi / m_edges * ( i + 1.0 );
            double nextInnerAngle = angle + inAngle + VGlobal::pi_2 + VGlobal::twopi / m_edges * ( i + 0.5 );
            if( m_type != polygon )
            {
                p.setX( m_innerRadius * cos( nextInnerAngle ) );
                p.setY( m_innerRadius * sin( nextInnerAngle ) );
 
                if( m_roundness == 0.0 )
                    lineTo( p );
                else
                {
                    p2.setX( m_outerRadius *
                        cos( angle + VGlobal::pi_2 + VGlobal::twopi / m_edges * ( i ) ) -
                        cos( angle + VGlobal::twopi / m_edges * ( i ) ) * outerRoundness );
                    p2.setY( m_outerRadius *
                        sin( angle + VGlobal::pi_2 + VGlobal::twopi / m_edges * ( i ) ) -
                        sin( angle + VGlobal::twopi / m_edges * ( i ) ) * outerRoundness );
 
                    p3.setX( m_innerRadius * cos( nextInnerAngle ) +
                        cos( angle + inAngle + VGlobal::twopi / m_edges * ( i + 0.5 ) ) * innerRoundness );
                    p3.setY( m_innerRadius * sin( nextInnerAngle ) +
                        sin( angle + inAngle + VGlobal::twopi / m_edges * ( i + 0.5 ) ) * innerRoundness );
 
                    if( m_type == gear )
                    {
                        lineTo( p2 );
                        lineTo( p3 );
                        lineTo( p );
                    }
                    else
                        curveTo( p2, p3, p );
                }
            }
 
            p.setX( m_outerRadius * cos( nextOuterAngle ) );
            p.setY( m_outerRadius * sin( nextOuterAngle ) );
 
            if( m_roundness == 0.0 )
                lineTo( p );
            else
            {
                p2.setX( m_innerRadius * cos( nextInnerAngle ) -
                    cos( angle + inAngle + VGlobal::twopi / m_edges * ( i + 0.5 ) ) * innerRoundness );
                p2.setY( m_innerRadius * sin( nextInnerAngle ) -
                    sin( angle + inAngle + VGlobal::twopi / m_edges * ( i + 0.5 ) ) * innerRoundness );
 
                p3.setX( m_outerRadius * cos( nextOuterAngle ) +
                    cos( angle + VGlobal::twopi / m_edges * ( i + 1.0 ) ) * outerRoundness );
                p3.setY( m_outerRadius * sin( nextOuterAngle ) +
                    sin( angle + VGlobal::twopi / m_edges * ( i + 1.0 ) ) * outerRoundness );
 
                if( m_type == gear )
                {
                    lineTo( p2 );
                    lineTo( p3 );
                    lineTo( p );
                }
                else
                    curveTo( p2, p3, p );
            }
        }
    }
    if( m_type == wheel || m_type == framed_star )
    {
        close();
        for ( int i = m_edges - 1; i >= 0; --i )
        {
            double nextOuterAngle = angle + VGlobal::pi_2 + VGlobal::twopi / m_edges * ( i + 1.0 );
            p.setX( m_outerRadius * cos( nextOuterAngle ) );
            p.setY( m_outerRadius * sin( nextOuterAngle ) );
            lineTo( p );
        }
    }
    close();
 
    // translate path to center:
    TQWMatrix m;
    m.translate( m_center.x(), m_center.y() );
 
    // only tranform the path data
    VTransformCmd cmd( 0L, m );
    cmd.VVisitor::visitVPath( *this );
 
    setFillRule( evenOdd );
 
    m_matrix.reset();
}
 
double
VStar::getOptimalInnerRadius( uint edges, double outerRadius, uint /*innerAngle*/ )
{
    int j = (edges % 2 == 0 ) ? ( edges - 2 ) / 2 : ( edges - 1 ) / 2;
 
    // get two well chosen lines of the star
    KoPoint p1( outerRadius * cos( VGlobal::pi_2 ), outerRadius * sin( VGlobal::pi_2 ) );
    int jumpto = ( j ) % edges;
    double nextOuterAngle = VGlobal::pi_2 + VGlobal::twopi / edges * jumpto;
    KoPoint p2( outerRadius * cos( nextOuterAngle ), outerRadius * sin( nextOuterAngle ) );
 
    nextOuterAngle = VGlobal::pi_2 + VGlobal::twopi / edges;
    KoPoint p3( outerRadius * cos( nextOuterAngle ),
                outerRadius * sin( nextOuterAngle ) );
    jumpto = ( edges - j + 1 ) % edges;
    nextOuterAngle = VGlobal::pi_2 + VGlobal::twopi / edges * jumpto;
    KoPoint p4( outerRadius * cos( nextOuterAngle ), outerRadius * sin( nextOuterAngle ) );
 
    // calc (x, y) -> intersection point
    double b1 = ( p2.y() - p1.y() ) / ( p2.x() - p1.x() );
    double b2 = ( p4.y() - p3.y() ) / ( p4.x() - p3.x() );
    double a1 = p1.y() - b1 * p1.x();
    double a2 = p3.y() - b2 * p3.x();
    double x = -( a1 - a2 ) / ( b1 - b2 );
    double y = a1 + b1 * x;
    // calc inner radius from intersection point and center
    return sqrt( x * x + y * y );
}
 
TQString
VStar::name() const
{
    TQString result = VObject::name();
    return !result.isEmpty() ? result : i18n( "Star" );
}
 
void
VStar::save( TQDomElement& element ) const
{
    VDocument *doc = document();
    if( doc && doc->saveAsPath() )
    {
        VPath::save( element );
        return;
    }
 
    if( state() != deleted )
    {
        TQDomElement me = element.ownerDocument().createElement( "STAR" );
        element.appendChild( me );
 
        // save fill/stroke untransformed
        VPath path( *this );
        VTransformCmd cmd( 0L, m_matrix.invert() );
        cmd.visit( path );
        path.VObject::save( me );
        //VObject::save( me );
 
        me.setAttribute( "cx", m_center.x() );
        me.setAttribute( "cy", m_center.y() );
 
        me.setAttribute( "outerradius", m_outerRadius );
        me.setAttribute( "innerradius", m_innerRadius );
        me.setAttribute( "edges", m_edges );
 
        me.setAttribute( "angle", m_angle );
        me.setAttribute( "innerangle", m_innerAngle );
 
        me.setAttribute( "roundness", m_roundness );
 
        me.setAttribute( "type", m_type );
 
        TQString transform = buildSvgTransform();
        if( !transform.isEmpty() )
            me.setAttribute( "transform", transform );
    }
}
 
void
VStar::load( const TQDomElement& element )
{
    setState( normal );
 
    TQDomNodeList list = element.childNodes();
    for( uint i = 0; i < list.count(); ++i )
        if( list.item( i ).isElement() )
            VObject::load( list.item( i ).toElement() );
 
    m_center.setX( KoUnit::parseValue( element.attribute( "cx" ) ) );
    m_center.setY( KoUnit::parseValue( element.attribute( "cy" ) ) );
 
    m_outerRadius  = KoUnit::parseValue( element.attribute( "outerradius" ) );
    m_innerRadius  = KoUnit::parseValue( element.attribute( "innerradius" ) );
    m_edges  = element.attribute( "edges" ).toUInt();
 
    m_innerAngle  = element.attribute( "innerangle" ).toUInt();
    m_angle = element.attribute( "angle" ).toDouble();
 
    m_roundness  = element.attribute( "roundness" ).toDouble();
 
    m_type =(VStar::VStarType) element.attribute( "type" ).toInt();
 
    init();
 
    TQString trafo = element.attribute( "transform" );
    if( !trafo.isEmpty() )
        transform( trafo );
}
 
VPath* 
VStar::clone() const
{
    return new VStar( *this );
}