#ifndef __CAMERA_H
#define __CAMERA_H

#include "Vector3.h"
#include "AxisAlignedBox3.h"

namespace GtpVisibilityPreprocessor {

class KdTree;
class SceneGraph;


class Camera
{
public:
  Vector3 mPosition;
  Vector3 mDirection;
  /** up vector takes into account the FOV at a unit distance from the origin */
  Vector3 mUp;
  /** right vector takes into account the FOV at a unit distance from the origin */
  Vector3 mRight;

  float mFovy;
  int mWidth;
  int mHeight;
  
  Camera() {
    mWidth = 1400;
    mHeight = 1000;
    mFovy = 90.0f*(float)M_PI/180.0f;
  }
  
  void Precompute() {
    mDirection.Normalize();
    Vector3 side = CrossProd(Vector3(0,1,0), mDirection);
    mUp = Normalize(CrossProd(side, mDirection));
    mRight = Normalize(CrossProd(mDirection, mUp));
    float k = tan(mFovy/2);
    mUp *= k;
    mRight *= k*mWidth/mHeight;
  }

  void SetPosition(const Vector3 &pos) {
    mPosition = pos;
    Precompute();
  }

	void SetDirection(const Vector3 &dir) {
    mDirection = dir;
    Precompute();
  }

  void LookInBox(const AxisAlignedBox3 &box)
  {
    mDirection = Vector3(0,0,1); 
    mPosition = box.Center();
    Precompute();
  }
    

  void LookAtBox(const AxisAlignedBox3 &box)
  {
    mDirection = box.Max() - box.Min();
    mPosition = box.Min() - mDirection;
    Precompute();
  }
  
  bool
  SnapImage(string filename,
			KdTree *tree,
			SceneGraph *sceneGraph
			);

  void SetupRay(Ray &ray, const int x, const int y);

};

};

#endif