/*

 * Pyrit Ray Tracer

 * file: scene.h

 *

 * Radek Brich, 2006-2007

 */

#ifndef SCENE_H

#define SCENE_H

#include <vector>

#include <typeinfo>

#include "noise.h"

#include "vector.h"

#include "quaternion.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 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():

		pos(Vector3(0,0,0)), colour(Colour(1,1,1)), cast_shadows(true) {};

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

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

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

};

class Texture

{

public:

	virtual Colour evaluate(Vector3 point) = 0;

};

class Material

{

public:

	Colour colour;

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

	Float reflectivity; // how much reflective is the surface

	Float transmissivity, refract_index; // part of light which can be refracted; index of refraction

	Texture *texture;

	Material(const Colour &acolour): colour(acolour), texture(NULL)

	{

		ambient = 0.2;

		diffuse = 0.8;

		specular = 0.2;

		shininess = 0.5;

		reflectivity = 0.2;

		transmissivity = 0.0;

		refract_index = 1.3;

	}

	void setPhong(const Float amb, const Float dif, const Float spec, const Float shin)

		{ ambient = amb; diffuse = dif; specular = spec; shininess = shin; };

	void setReflectivity(const Float refl) { reflectivity = refl; };

	void setTransmissivity(const Float trans, const Float rindex)

		{ transmissivity = trans; refract_index = rindex; };

};

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;

	// intersection with AABB

	virtual bool intersect_bbox(const BBox &bbox) const = 0;

	// normal at point P

	virtual const Vector3 normal(const 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;

	bool intersect_bbox(const BBox &bbox) const;

	const Vector3 normal(const 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; };

	bool intersect_bbox(const BBox &bbox) const;

	const Vector3 normal(const Vector3 &P) const;

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

};

class Vertex

{

public:

	Vector3 P;

	Vertex(const Vector3 &aP): P(aP) {};

};

class NormalVertex: public Vertex

{

public:

	Vector3 N;

	NormalVertex(const Vector3 &aP): Vertex(aP) {};

	NormalVertex(const Vector3 &aP, const Vector3 &aN): Vertex(aP), N(aN) {};

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

	void setNormal(const Vector3 &aN) { N = aN; };

};

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

	Vector3 N;

	bool smooth;

	const Vector3 smooth_normal(const Vector3 &P) const

	{

#ifdef TRI_BARI_PRE

		const Vector3 &NA = static_cast<NormalVertex*>(A)->N;

		const Vector3 &NB = static_cast<NormalVertex*>(B)->N;

		const Vector3 &NC = static_cast<NormalVertex*>(C)->N;

		static const int modulo3[5] = {0,1,2,0,1};

		register const int ku = modulo3[k+1];

		register const int kv = modulo3[k+2];

		const Float pu = P[ku] - A->P[ku];

		const Float pv = P[kv] - A->P[kv];

		const Float u = pv * bnu + pu * bnv;

		const Float v = pu * cnv + pv * cnu;

		Vector3 n = NA + u * (NB - NA) + v * (NC - NA);

		n.normalize();

		return n;

#else

		return N; // not implemented for other algorithms

#endif

	};

public:

	Vertex *A, *B, *C;

	Triangle(Vertex *aA, Vertex *aB, Vertex *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;};

	bool intersect_bbox(const BBox &bbox) const;

	const Vector3 normal(const Vector3 &P) const { return (smooth ? smooth_normal(P) : N); };

	const Vector3 getNormal() const { return N; };

	void setSmooth() { smooth = true; };//(typeid(*A) == typeid(*B) == typeid(*C) == typeid(NormalVertex)); };

	void setFlat() { smooth = false; };

	bool getSmooth() const { return smooth; };

	BBox get_bbox() const;

};

#endif