//-*-C++-*- /* ************************************************************************** description -------------------- copyright : (C) 2002 by Andreas Zehender email : zehender@kde.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. * * * **************************************************************************/ #ifndef PMSPLINESEGMENT_H #define PMSPLINESEGMENT_H #ifdef HAVE_CONFIG_H #include <config.h> #endif #include "pmvector.h" #include <tqvaluelist.h> /** * Helper class for splines * * Each instance of this class represents one spline segment. A point * on the segment is given by the equation * * fi(t) = A[i] * t^3 + B[i] * t^2 + C[i] * t + D[i] * * with t ranging from 0 to 1. */ class PMSplineSegment { public: /** * Standard constructor */ PMSplineSegment( ) { m_a[0] = m_b[0] = m_c[0] = m_d[0] = 0.0; m_a[1] = m_b[1] = m_c[1] = m_d[1] = 0.0; } /** * Copy constructor */ PMSplineSegment( const PMSplineSegment& s ) { int i; for( i = 0; i < 2; i++ ) { m_a[i] = s.m_a[i]; m_b[i] = s.m_b[i]; m_c[i] = s.m_c[i]; m_d[i] = s.m_d[i]; } } /** * Assigns s to the segment */ PMSplineSegment& operator= ( const PMSplineSegment& s ) { int i; for( i = 0; i < 2; i++ ) { m_a[i] = s.m_a[i]; m_b[i] = s.m_b[i]; m_c[i] = s.m_c[i]; m_d[i] = s.m_d[i]; } return *this; } /** * Returns a 2D vector with the point on the spline segment */ PMVector point( double t ) const; /** * Returns the gradient on the spline */ PMVector gradient( double t ) const; /** * Calculates the spline parameters for the linear spline type */ void calculateLinear( const PMVector& p1, const PMVector& p2 ); /** * Calculates the spline parameters for the quadratic spline type */ void calculateQuadratic( const PMVector& p1, const PMVector& p2, const PMVector& p3 ); /** * Calculates the spline parameters for the cubic spline type */ void calculateCubic( const PMVector& p1, const PMVector& p2, const PMVector& p3, const PMVector& p4 ); /** * Calculates the spline parameters for the bezier spline type */ void calculateBezier( const PMVector& p1, const PMVector& p2, const PMVector& p3, const PMVector& p4 ); /** * Calculates the spline parameters for the quadric bezier */ void calculateQuadricBezier( const PMVector& p1, const PMVector& p2, const PMVector& p3 ); private: double m_a[2], m_b[2], m_c[2], m_d[2]; }; typedef TQValueList<PMSplineSegment> PMSegmentList; typedef TQValueList<PMSegmentList> PMSegmentListList; #endif