/*
   model/face.h
   This file is part of the Osirion project and is distributed under
   the terms of the GNU General Public License version 2
*/

#ifndef __INCLUDED_MODEL_FACE_H__
#define __INCLUDED_MODEL_FACE_H__

#include <string>

#include "math/vector2f.h"
#include "math/vector3f.h"
#include "model/material.h"

namespace model
{

/** @brief A class representing the plane of a single model face
 *  all points p(x, y, z) on the plane satisfy the general equation
 *  x*a() + y*b() + z*c() + d() = 0
 */
class Face
{
public:
	/// a plane defined by 3 points in space
	Face(math::Vector3f const & point0, math::Vector3f const &point1, math::Vector3f const &point2);

	/// copy constructor
	Face(Face const & other);

	/// normal of the plane, not normalized to lenght 1
	inline math::Vector3f const & normal() const {
		return face_normal;
	}

	/// the points defining the plane.
	/// @param index 0 <= i < 3
	inline math::Vector3f const & point(size_t index) const {
		return face_point[index];
	}

	/// face material
	inline Material *material() const {
		return face_material;
	}

	/// first parameter of the general plane equation
	inline float a() const {
		return face_normal[0];
	}

	/// second parameter of the general plane equation
	inline float b() const {
		return face_normal[1];
	}

	/// third param of the general plane equation
	inline float c() const {
		return face_normal[2];
	}

	/// fourth parameter of the general plane equation
	inline float d() const {
		return pd;
	}

	/// indidcates if this plane was generated from a detail brush
	inline bool detail() const {
		return face_detail;
	}

	/// surface flags
	inline unsigned int surface_flags() const {
		return face_surface_flags;
	}

	/**
	 * @brief return texture transformation vectors
	 * @param index 0 <= i < 2
	 */
	inline const math::Vector3f &tex_vec(size_t index) {
		return face_tex_vec[index];
	}

	/// return texture shift
	inline const math::Vector2f &tex_shift() {
		return face_tex_shift;
	}

	inline void set_material(Material *material) {
		face_material = material;
	}

	inline void set_detail(const bool detail = true) {
		face_detail = detail;
	}

	inline void set_surface_flags(const unsigned int flags) {
		face_surface_flags = flags;
	}

	/**
	 * @brief return texture transformation vectors
	 * @param index 0 <= i < 2
	 */
	inline math::Vector3f &get_tex_vec(size_t index) {
		return face_tex_vec[index];
	}

	/// return texture shift
	inline math::Vector2f &get_tex_shift() {
		return face_tex_shift;
	}

private:
	math::Vector3f		face_normal;
	math::Vector3f		face_point[3];

	math::Vector3f		face_tex_vec[2];
	math::Vector2f		face_tex_shift;

	Material		*face_material;
	unsigned int		face_surface_flags;
	bool			face_detail;
	float 			pd;
};

}

#endif // __INCLUDED_MODEL_FACE_H__