PerspectiveCamera.cxx

   1 #include <limits>
   2 #include <iostream>
   3 #include <cassert>
   4
   5 #include "PerspectiveCamera.hxx"
   6
   7 PerspectiveCamera::PerspectiveCamera()
   8   : Camera()
   9 {
  10 }
  11
  12 PerspectiveCamera::PerspectiveCamera(const Vec3f& pos,
  13                                      const Vec3f& dir,
  14                                      const Vec3f& up,
  15                                      float angle,
  16                                      int resX,
  17                                      int resY)
  18   : Camera(resX,resY),
  19     m_pos(pos),
  20     m_dir(dir),
  21     m_up(up),
  22     m_angle(angle)
  23 {
  24   // preprocess the values and fill the rest of the member variables here
  25   m_dir.normalize();
  26   m_up.normalize();
  27
  28   // compute local coordinate system
  29   m_zAxis = dir;
  30   m_xAxis = dir.cross(up);
  31   m_yAxis = m_xAxis.cross(m_zAxis);
  32
  33   m_xAxis.normalize();
  34   m_yAxis.normalize();
  35   m_zAxis.normalize();
  36
  37   m_aspect = resX/static_cast<float>(resY);
  38
  39   // derive focal length from opening angle
  40   float angle_in_rad = angle * M_PI / 180.0f;
  41   m_focus = 1.0 / tan(angle_in_rad * 0.5);
  42 }
  43
  44 PerspectiveCamera::~PerspectiveCamera()
  45 {
  46 }
  47
  48 PerspectiveCamera::PerspectiveCamera(const PerspectiveCamera& )
  49 {
  50
  51 }
  52
  53 PerspectiveCamera&
  54 PerspectiveCamera::operator=(const PerspectiveCamera& )
  55 {
  56   assert(!"Not implemented!");
  57   return *this;
  58 }
  59
  60 bool
  61 PerspectiveCamera::InitRay(float x, //!< pixel x-coordinate
  62                            float y, //!< pixel y-coordinate
  63                            Ray& ray //!< should be filled by this function
  64                            ) const
  65 {
  66   // define direction,position and maximum hit distance of Ray here
  67   Vec3f dir = m_xAxis * ( 2.0f * ((x/static_cast<float>(m_resX) - 0.5 ) * m_aspect ) )
  68     + m_yAxis * ( 2.0f * (y/static_cast<float>(m_resY) - 0.5 ) )
  69     + ( m_zAxis * m_focus );
  70   dir.normalize();
  71
  72   ray.setDir(dir);
  73   ray.setOrigin(m_pos);
  74   float t = std::numeric_limits<float>::max();
  75   ray.setT(t);
  76
  77   return true;
  78 }