Subversion Repositories gelsvn

Rev

Rev 89 | Details | Compare with Previous | Last modification | View Log | RSS feed

Rev Author Line No. Line
595 jab 1 
/* ----------------------------------------------------------------------- *
2 
 * This file is part of GEL, http://www.imm.dtu.dk/GEL
3 
 * Copyright (C) the authors and DTU Informatics
4 
 * For license and list of authors, see ../../doc/intro.pdf
5 
 * ----------------------------------------------------------------------- */
6 
 
7 
/** @file UnitVector.h
8 
 * @brief Unitvector coded with two angles - possibly not efficient.
9 
 */
10 
 
12 jab 11 
#ifndef __CGLA_UNITVECTOR_H__
12 
#define __CGLA_UNITVECTOR_H__
2 bj 13 
 
14 
#include "CGLA.h"
15 
#include "Vec3f.h"
16 
#include "TableTrigonometry.h"
17 
 
18 
namespace CGLA
19 
{
12 jab 20 
  namespace TT=TableTrigonometry;
2 bj 21 
 
89 jab 22 
  /** \brief The UnitVector stores a unit length vector as two angles.
2 bj 23 
 
12 jab 24 
  A vector stored as two (fix point) angles is much smaller than
25 
  vector stored in the usual way. On a 32 bit architecture this
26 
  class should take up four bytes. not too bad. */
27 
  class UnitVector
28 
    {
29 
      TT::Angle theta, phi;
30 
 
31 
      void encode(const Vec3f& v)
2 bj 32 
	{
12 jab 33 
	  theta = TT::t_atan(std::sqrt(CGLA::sqr(v[0])+CGLA::sqr(v[1])), v[2]);
34 
	  phi   = TT::t_atan(v[0],v[1]);
35 
	}
2 bj 36 
 
12 jab 37 
    public:
2 bj 38 
 
12 jab 39 
      /// Construct unitvector from normal vector
40 
      explicit UnitVector(const Vec3f& v) {encode(v);}
2 bj 41 
 
12 jab 42 
      /// Construct default unit vector
43 
      explicit UnitVector(): theta(0), phi(0) {}
2 bj 44 
 
12 jab 45 
      /// Get theta angle
46 
      float t() const {return TT::angle2float(theta);}
2 bj 47 
 
12 jab 48 
      /// Get phi angle
49 
      float f() const {return TT::angle2float(phi);}
2 bj 50 
 
12 jab 51 
      /// Reconstruct Vec3f from unit vector
52 
      operator Vec3f() const
53 
	{
54 
	  float costf = TT::t_cos(theta);
55 
	  return Vec3f(TT::t_cos(phi)*costf ,
56 
		       TT::t_sin(phi)*costf,
57 
		       TT::t_sin(theta));
58 
	}
2 bj 59 
 
12 jab 60 
      /// Test for equality.
61 
      bool operator==(const UnitVector& u) const
2 bj 62 
	{
12 jab 63 
	  return theta == u.theta && phi == u.phi;
2 bj 64 
	}
12 jab 65 
    };
2 bj 66 
 
12 jab 67 
 
68 
  /// Inline output operator.
69 
  inline std::ostream& operator<<(std::ostream& os, const UnitVector& u)
70 
    {
71 
      os << "<v=" << u.t() << " h=" << u.f() << ">";
72 
      return os;
73 
    }
74 
 
2 bj 75 
}
76 
#endif