/*

 * C++ RayTracer

 * file: scene.h

 *

 * Radek Brich, 2006

 */

#ifndef SCENE_H

#define SCENE_H

#include <vector>

#include "noise.h"

#include "vector.h"

/*

triangle intersection alghoritm

chooses are:

TRI_PLUCKER

TRI_BARI

TRI_BARI_PRE

*/

#if !defined(TRI_PLUCKER) && !defined(TRI_BARI) && !defined(TRI_BARI_PRE)

#	define TRI_BARI_PRE

#endif

using namespace std;

class Ray

{

public:

	Vector3 o, dir;

	Ray(const Vector3 &ao, const Vector3 &adir):

		o(ao), dir(adir) {};

};

class Quaternion

{

public:

	Float a,b,c,d;

	Quaternion(): a(0), b(0), c(0), d(0) {};

	Quaternion(const Float aa, const Float ab, const Float ac, const Float ad):

		a(aa), b(ab), c(ac), d(ad) {};

	Quaternion(const Vector3& v): a(1), b(v.x), c(v.y), d(v.z) {};

	Vector3 toVector() { return Vector3(b/a, c/a, d/a); };

	Quaternion normalize()

	{

		Float f = 1.0f / sqrtf(a * a + b * b + c * c + d * d);

		a *= f;

		b *= f;

		c *= f;

		d *= f;

		return *this;

	};

	friend Quaternion operator*(const Quaternion &q1, const Quaternion &q2)

	{

		return Quaternion(

			q1.a*q2.a - q1.b*q2.b - q1.c*q2.c - q1.d*q2.d,

			q1.a*q2.b + q1.b*q2.a + q1.c*q2.d - q1.d*q2.c,

			q1.a*q2.c + q1.c*q2.a + q1.d*q2.b - q1.b*q2.d,

			q1.a*q2.d + q1.d*q2.a + q1.b*q2.c - q1.c*q2.b);

	};

	friend Quaternion conjugate(const Quaternion &q)

	{

		return Quaternion(q.a, -q.b, -q.c, -q.d);

	}

};

class Camera

{

public:

	Vector3 eye, p, u, v;

	Float f;

	Camera(): eye(0,0,10), p(0,0,-1), u(-1,0,0), v(0,1,0), f(3.14/4.0) {};

	Camera(const Vector3 &C, const Vector3 &ap, const Vector3 &au, const Vector3 &av):

		eye(C), p(ap), u(au), v(av), f(3.14/4.0) {};

	void setEye(const Vector3 &aeye) { eye = aeye; };

	void setFocalLength(const Float af) { f = af; };

	void rotate(const Quaternion &q);

	void move(const Float fw, const Float left, const Float up);

};

/* axis-aligned bounding box */

class BBox

{

public:

	Vector3 L;

	Vector3 H;

	BBox(): L(), H() {};

	BBox(const Vector3 aL, const Vector3 aH): L(aL), H(aH) {};

	Float w() { return H.x-L.x; };

	Float h() { return H.y-L.y; };

	Float d() { return H.z-L.z; };

	bool intersect(const Ray &ray, Float &a, Float &b);

};

class Light

{

public:

	Vector3 pos;

	Colour colour;

	bool cast_shadows;

	Light(const Vector3 &position, const Colour &acolour):

		pos(position), colour(acolour), cast_shadows(true) {};

	void castShadows(bool cast) { cast_shadows = cast; };

};

class Texture

{

public:

	Colour colour;

	Colour evaluate(Vector3 point)

	{

		Float sum = 0.0;

		for (int i = 1; i < 5; i++)

			sum += fabsf(perlin(point.x*i, point.y*i, point.z*i))/i;

		Float value = sinf(point.x + sum)/2 + 0.5;

		return Colour(value*colour.r, value*colour.g, value*colour.b);

	};

};

class Material

{

public:

	Float ambient, diffuse, specular, shininess; // Phong constants

	Float reflection; // how much reflectife is the surface

	Float refraction; // refraction index

	Float transmitivity;

	Texture texture;

	Material(const Colour &acolour) {

		texture.colour = acolour;

		ambient = 0.1;

		diffuse = 0.5;

		specular = 0.1;

		shininess = 0.5;

		reflection = 0.5;

	}

};

class Shape

{

public:

	Material *material;

	Shape() {};

	virtual ~Shape() {};

	// first intersection point

	virtual bool intersect(const Ray &ray, Float &dist) const = 0;

	// all intersections (only for CSG)

	virtual bool intersect_all(const Ray &ray, Float dist, vector<Float> &allts) const = 0;

	// normal at point P

	virtual Vector3 normal(Vector3 &P) const = 0;

	virtual BBox get_bbox() const = 0;

};

class ShapeList: public vector<Shape*>

{

};

class Sphere: public Shape

{

	Float sqr_radius;

	Float inv_radius;

public:

	Vector3 center;

	Float radius;

	Sphere(const Vector3 &acenter, const Float aradius, Material *amaterial):

		sqr_radius(aradius*aradius), inv_radius(1.0f/aradius),

		center(acenter), radius(aradius) { material = amaterial; }

	bool intersect(const Ray &ray, Float &dist) const;

	bool intersect_all(const Ray &ray, Float dist, vector<Float> &allts) const;

	Vector3 normal(Vector3 &P) const { return (P - center) * inv_radius; };

	BBox get_bbox() const;

};

class Box: public Shape

{

	Vector3 L;

	Vector3 H;

public:

	Box(const Vector3 &aL, const Vector3 &aH, Material *amaterial): L(aL), H(aH)

	{

		for (int i = 0; i < 3; i++)

			if (L.cell[i] > H.cell[i])

				swap(L.cell[i], H.cell[i]);

		material = amaterial;

	};

	bool intersect(const Ray &ray, Float &dist) const;

	bool intersect_all(const Ray &ray, Float dist, vector<Float> &allts) const { return false; };

	Vector3 normal(Vector3 &P) const;

	BBox get_bbox() const { return BBox(L, H); };

};

class Triangle: public Shape

{

#ifdef TRI_BARI_PRE

	Float nu, nv, nd;

	int k; // dominant axis

	Float bnu, bnv;

	Float cnu, cnv;

#endif

#ifdef TRI_BARI

	int k; // dominant axis

#endif

#ifdef TRI_PLUCKER

	Float pla[6], plb[6], plc[6];

#endif

public:

	Vector3 A, B, C, N;

	Triangle(const Vector3 &aA, const Vector3 &aB, const Vector3 &aC, Material *amaterial);

	bool intersect(const Ray &ray, Float &dist) const;

	bool intersect_all(const Ray &ray, Float dist, vector<Float> &allts) const {return false;};

	Vector3 normal(Vector3 &) const { return N; };

	BBox get_bbox() const;

};

#endif