src/movement.h

   1 /*
   2   Copyright (c) 2006 Paolo Capriotti <p.capriotti@gmail.com>
   3             (c) 2006 Maurizio Monge <maurizio.monge@kdemail.net>
   4
   5   This program is free software; you can redistribute it and/or modify
   6   it under the terms of the GNU General Public License as published by
   7   the Free Software Foundation; either version 2 of the License, or
   8   (at your option) any later version.
   9 */
  10
  11 #ifndef MOVEMENT_H
  12 #define MOVEMENT_H
  13
  14 #include <QPoint>
  15 #include <iostream>
  16
  17 /**
  18   * Abstract class representing a parameterization of a curve
  19   * in a plane and a rotation angle.
  20   * The parameter @a t for both the position and the rotation
  21   * is assumed to lie in the closed interval [0,1].
  22   */
  23 class Movement {
  24 public:
  25   virtual ~Movement() { }
  26   virtual QPoint pos(double t) const = 0;
  27   virtual double rotation(double /*t*/) const { return 0.0; }
  28
  29   static double sigmoid(double t);
  30   static double half_sigmoid(double t);
  31 };
  32
  33 /**
  34   * A straight path, no rotation.
  35   */
  36 class LinearMovement : public Movement {
  37   QPoint m_from;
  38   QPoint m_velocity;
  39 public:
  40   /// create a path from @a from to @a to.
  41   LinearMovement(const QPoint& from, const QPoint& to, bool /*rotate*/);
  42
  43   virtual QPoint pos(double t) const;
  44 };
  45
  46 /**
  47   * An L-shaped path. First along the shortest side, then along the other.
  48   * Use an exponential parameterization for the longest side.
  49   */
  50 class LMovement : public Movement {
  51   QPoint m_from;
  52   QPoint m_velocity;
  53   bool m_rotate;
  54   double (*m_x)(double);
  55   double (*m_y)(double);
  56
  57   static double linear(double t) { return t; }
  58   static double nonlinear(double t);
  59 public:
  60   /// create an L-path from @a from to @a to.
  61   LMovement(const QPoint& from, const QPoint& to, bool rotate = false);
  62
  63   virtual QPoint pos(double t) const;
  64   virtual double rotation(double t) const;
  65 };
  66
  67 /**
  68   * Movement mixin: apply to a Movement to get a sigmoidal
  69   * variant of it.
  70   */
  71 template <typename Mov>
  72 class SigmoidalMovement : public Mov {
  73 public:
  74   SigmoidalMovement(const QPoint& from, const QPoint& to, bool rotate = false)
  75   : Mov(from, to, rotate) { }
  76
  77   virtual QPoint pos(double t) const {
  78     return Mov::pos(Movement::sigmoid(t));
  79   }
  80 };
  81
  82 template <typename Mov>
  83 class HalfSigmoidalMovement : public Mov {
  84 public:
  85   HalfSigmoidalMovement(const QPoint& from, const QPoint& to, bool rotate = false)
  86   : Mov(from, to, rotate) { }
  87
  88   virtual QPoint pos(double t) const {
  89     return Mov::pos(Movement::half_sigmoid(t));
  90   }
  91 };
  92
  93 #endif // MOVEMENT_H