You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
433 lines
9.2 KiB
433 lines
9.2 KiB
/* 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.
|
|
*/
|
|
|
|
#ifndef __VSEGMENT_H__
|
|
#define __VSEGMENT_H__
|
|
|
|
#include <qptrlist.h>
|
|
#include <qvaluelist.h>
|
|
|
|
#include <KoPoint.h>
|
|
#include <KoRect.h>
|
|
|
|
#include "vglobal.h"
|
|
#include <koffice_export.h>
|
|
|
|
class QDomElement;
|
|
class VPainter;
|
|
|
|
/**
|
|
* A class representing lines and beziers. We waste some KoPoints, if we
|
|
* would use only lines, but this makes it easy to convert the segment types
|
|
* into each other. Make sure yourself, that you pass values to functions within
|
|
* proper ranges.
|
|
*/
|
|
|
|
class KARBONBASE_EXPORT VSegment
|
|
{
|
|
friend class VSubpath;
|
|
friend class VSubpathIterator;
|
|
|
|
public:
|
|
/**
|
|
* Tells which control point is "fixed" i.e. located at the
|
|
* corresponding knot and invisible. This flag makes no sense for
|
|
* line segments.
|
|
*/
|
|
enum VCtrlPointFixing
|
|
{
|
|
none = 0,
|
|
first = 1,
|
|
second = 2
|
|
};
|
|
|
|
enum VState
|
|
{
|
|
normal,
|
|
deleted
|
|
};
|
|
|
|
|
|
VSegment( unsigned short deg = 3 );
|
|
|
|
VSegment( const VSegment& segment );
|
|
|
|
~VSegment();
|
|
|
|
/**
|
|
* Returns the segment's degree, which is identical to the number of nodes.
|
|
* For cubic beziers it is "three" and "one" for lines.
|
|
*/
|
|
unsigned short degree() const
|
|
{
|
|
return m_degree;
|
|
}
|
|
|
|
/**
|
|
* Sets the segment's degree and thus resizes the array of node data.
|
|
* The node data is copied from the old knot "backwards".
|
|
*/
|
|
void setDegree( unsigned short deg );
|
|
|
|
/**
|
|
* Tests for the segment type ("begin", "line" or "curve").
|
|
*/
|
|
bool isBegin() const { return (degree() == 1) && !prev(); }
|
|
bool isLine() const { return (degree() == 1) && prev(); }
|
|
bool isCurve() const { return degree() > 1; }
|
|
|
|
/**
|
|
* Returns the segment state.
|
|
*/
|
|
VState state() const
|
|
{
|
|
return m_state;
|
|
}
|
|
|
|
/**
|
|
* Sets the segment state.
|
|
*/
|
|
void setState( VState state )
|
|
{
|
|
m_state = state;
|
|
}
|
|
|
|
|
|
/**
|
|
* Returns the segment's point with index 0 <= i < degree().
|
|
*/
|
|
const KoPoint& point( int i ) const
|
|
{
|
|
return m_nodes[ i ].m_vector;
|
|
}
|
|
|
|
/**
|
|
* This is a convenience function. It returns the point with index
|
|
* 0 <= i <= degree() while p( 0 ) is the knot of the previous
|
|
* segment.
|
|
*/
|
|
const KoPoint& p( int i ) const
|
|
{
|
|
return i == 0
|
|
? prev()->knot()
|
|
: m_nodes[ --i ].m_vector;
|
|
}
|
|
|
|
/**
|
|
* Returns the knot. This is a convenience function using point().
|
|
*/
|
|
const KoPoint& knot() const
|
|
{
|
|
return point( degree() - 1 );
|
|
}
|
|
|
|
/**
|
|
* Sets the segment's point with index 0 <= i < degree() to "p".
|
|
*/
|
|
void setPoint( int i, const KoPoint& p )
|
|
{
|
|
m_nodes[ i ].m_vector = p;
|
|
}
|
|
|
|
/**
|
|
* This is a convenience function. It sets the point with index
|
|
* 0 <= i <= degree() to "p" while setP( 0 ) sets the knot of the
|
|
* previous segment.
|
|
*/
|
|
void setP( int i, const KoPoint& p )
|
|
{
|
|
if( i == 0 )
|
|
prev()->setKnot( p );
|
|
else
|
|
m_nodes[ --i ].m_vector = p;
|
|
}
|
|
|
|
/**
|
|
* Sets the knot. This is a convenience function.
|
|
*/
|
|
void setKnot( const KoPoint& p )
|
|
{
|
|
m_nodes[ degree() - 1 ].m_vector = p;
|
|
}
|
|
|
|
|
|
/**
|
|
* Returns true if the point with index 0 <= i < degree() is selected.
|
|
*/
|
|
bool pointIsSelected( int i ) const
|
|
{
|
|
return m_nodes[ i ].m_isSelected;
|
|
}
|
|
|
|
/**
|
|
* Returns true if the knot is selected. This is a convenience function.
|
|
*/
|
|
bool knotIsSelected() const
|
|
{
|
|
return m_nodes[ degree() - 1 ].m_isSelected;
|
|
}
|
|
|
|
/**
|
|
* Selects the point with index 0 <= i < degree().
|
|
*/
|
|
void selectPoint( int i, bool select = true )
|
|
{
|
|
m_nodes[ i ].m_isSelected = select;
|
|
}
|
|
|
|
/**
|
|
* Selects/deselects the knot of this segment.
|
|
*/
|
|
void selectKnot( bool select = true )
|
|
{
|
|
m_nodes[ degree() - 1 ].m_isSelected = select;
|
|
}
|
|
|
|
|
|
/**
|
|
* Returns index of the node at point p. Returns 0 if no
|
|
* segment point matches point p.
|
|
*/
|
|
// TODO: Move this function into "userland"
|
|
uint nodeNear( const KoPoint& p,
|
|
double isNearRange = VGlobal::isNearRange ) const;
|
|
|
|
|
|
/**
|
|
* Returns a pointer to the previous not deleted segment, if
|
|
* stored in a VSubpath.
|
|
*/
|
|
VSegment* prev() const;
|
|
|
|
/**
|
|
* Returns a pointer to the next not deleted segment, if
|
|
* stored in a VSubpath.
|
|
*/
|
|
VSegment* next() const;
|
|
|
|
/**
|
|
* Returns true if the segment is flat. That means it's height
|
|
* is smaller than flatness.
|
|
*/
|
|
bool isFlat( double flatness = VGlobal::flatnessTolerance ) const;
|
|
|
|
|
|
/**
|
|
* Calculates the point on this segment at parameter 0 <= t <= 1.
|
|
* This is a convenience wrapper for pointDerivativesAt().
|
|
*/
|
|
KoPoint pointAt( double t ) const;
|
|
|
|
/**
|
|
* Calculates the point and the derivatives of first and
|
|
* second order for 0 <= t <= 1.
|
|
*/
|
|
void pointDerivativesAt( double t, KoPoint* p = 0L,
|
|
KoPoint* d1 = 0L, KoPoint* d2 = 0L ) const;
|
|
|
|
|
|
/**
|
|
* Calculates the normalized tangent vector (length=1) at the point
|
|
* parameterized by 0 <= t <= 1. This is a convenience wrapper
|
|
* for pointTangentNormalAt(). Use the latter function directly if you
|
|
* need to calculate the point and normal vector or tangent vector
|
|
* at once.
|
|
*/
|
|
KoPoint tangentAt( double t ) const;
|
|
|
|
/**
|
|
* Calculates the point, the tangent vector and the normal vector for
|
|
* 0 <= t <= 1. The tangent vector and the normal vector are
|
|
* normalized (length=1).
|
|
*/
|
|
void pointTangentNormalAt( double t, KoPoint* p = 0L,
|
|
KoPoint* tn = 0L, KoPoint* n = 0L ) const;
|
|
|
|
|
|
/**
|
|
* Calculates the arclength from p0 to the point parametrized
|
|
* by 0 <= t <= 1. For beziers this function is a bit expensive.
|
|
*/
|
|
double length( double t = 1.0 ) const;
|
|
|
|
/**
|
|
* Calculates the chord length (the distance from the previous
|
|
* knot to the current knot).
|
|
*/
|
|
double chordLength() const;
|
|
|
|
/**
|
|
* Calculates the length of the control polygon.
|
|
*/
|
|
double polyLength() const;
|
|
|
|
|
|
/**
|
|
* Calculates the parameter of a point located at arclength len.
|
|
* This is the exact inverse operation of length( t ).
|
|
*/
|
|
double lengthParam( double len ) const;
|
|
|
|
|
|
/**
|
|
* Calculates the parameter of the nearest point on this segment
|
|
* to the point p. This function is pretty expensive.
|
|
*/
|
|
double nearestPointParam( const KoPoint& p ) const;
|
|
|
|
|
|
/**
|
|
* Calculates wether the tangent at the knot is exactly parallel to
|
|
* the tangent at p0 of the next segment. Returns false if the
|
|
* current segment is a "begin".
|
|
*/
|
|
bool isSmooth( const VSegment& next ) const;
|
|
|
|
bool isSmooth() const
|
|
{
|
|
return next()
|
|
? isSmooth( *next() )
|
|
: false;
|
|
}
|
|
|
|
|
|
/**
|
|
* Creates a reverted version of this segment. For example:
|
|
* if this segment is a line from A to B, the result is a
|
|
* line from B to A.
|
|
*/
|
|
VSegment* revert() const;
|
|
|
|
|
|
/**
|
|
* Splits the segment at parameter 0 <= t <= 1. Returns a pointer
|
|
* to the first segment and modifies the current one to
|
|
* be the second segment.
|
|
*/
|
|
VSegment* splitAt( double t );
|
|
|
|
|
|
/**
|
|
* Calculates height of point p above line AB.
|
|
*/
|
|
static double height(
|
|
const KoPoint& a,
|
|
const KoPoint& p,
|
|
const KoPoint& b );
|
|
|
|
|
|
/**
|
|
* Calculates whether lines A0A1 and B0B1 intersect.
|
|
*/
|
|
static bool linesIntersect(
|
|
const KoPoint& a0,
|
|
const KoPoint& a1,
|
|
const KoPoint& b0,
|
|
const KoPoint& b1 );
|
|
|
|
/**
|
|
* Returns true, if this segment intersects the other segment.
|
|
*/
|
|
bool intersects( const VSegment& segment ) const;
|
|
|
|
|
|
/**
|
|
* Returns a number > 0 if the point p is left, 0 if it's on and
|
|
* a number < 0 if it's right of the infinite line through the
|
|
* previous segment's knot and the current knot.
|
|
*/
|
|
double pointIsLeft( const KoPoint& p ) const
|
|
{
|
|
return
|
|
( knot().x() - prev()->knot().x() ) *
|
|
( p.y() - prev()->knot().y() )
|
|
-
|
|
( p.x() - prev()->knot().x() ) *
|
|
( knot().y() - prev()->knot().y() );
|
|
}
|
|
|
|
/**
|
|
* Calculates the bounding box.
|
|
*/
|
|
KoRect boundingBox() const;
|
|
|
|
|
|
void draw( VPainter* painter ) const;
|
|
|
|
// TODO: remove this backward compatibility function after koffice 1.3.x.
|
|
void load( const QDomElement& element );
|
|
|
|
|
|
/**
|
|
* Returns a pointer to a copy of this segment.
|
|
*/
|
|
VSegment* clone() const;
|
|
|
|
private:
|
|
/**
|
|
* Calculates the solutions of y(x) = 0 where 0 <= x <= 1. The
|
|
* returned parameters are not ordered.
|
|
*/
|
|
void rootParams( QValueList<double>& params ) const;
|
|
|
|
/**
|
|
* Calculates how often the control polygon crosses the x-axis.
|
|
*/
|
|
int controlPolygonZeros() const;
|
|
|
|
|
|
/**
|
|
* The segment degree. For (cubic) beziers "three", "one" for lines.
|
|
*/
|
|
unsigned short m_degree : 6;
|
|
|
|
/**
|
|
* The segment state.
|
|
*/
|
|
VState m_state : 2;
|
|
|
|
/**
|
|
* Node data.
|
|
*/
|
|
struct VNodeData
|
|
{
|
|
KoPoint m_vector;
|
|
bool m_isSelected;
|
|
};
|
|
|
|
/**
|
|
* A pointer to an array of node data.
|
|
*/
|
|
VNodeData* m_nodes;
|
|
|
|
|
|
/**
|
|
* Pointer to the previous segment.
|
|
*/
|
|
VSegment* m_prev;
|
|
|
|
/**
|
|
* Pointer to the next segment.
|
|
*/
|
|
VSegment* m_next;
|
|
};
|
|
|
|
#endif
|
|
|