#ifndef PERSPECTIVE_H

#define PERSPECTIVE_H

#include <vector>

#include <string>

#include "vector.h"

#include "matrix.h"

#include "surface.h"

class Perspective {

public:

	class Layer {

	public:

		IntPair2   dst_bounds;

		Pair2      src_bounds;

		IntVector2 src_size;

		Matrix3    back_matrix;

		Matrix3    back_alpha_matrix;

		Vector2    center;

	};

	typedef std::vector<Layer> LayerList;

	static Matrix3 make_matrix(

		const Vector2 &p0,

		const Vector2 &px,

		const Vector2 &py,

		const Vector2 &p1 );

	static Matrix3 matrix_mult(

		const Matrix3 &matrix,

		Real value );

	static Matrix3 normalize_matrix_by_det(

		const Matrix3 &matrix );

	static int truncate_line(

		Vector2 *out_points,

		const Pair2 &bounds,

		Real a,

		Real b,

		Real c );

	static Vector2 calc_optimal_resolution(

		const Vector2 &ox,

		const Vector2 &oy );

	static Vector3 make_alpha_matrix_col(

		Real w0,

		Real w1,

		const Vector3 &w_col );

	static Matrix3 make_alpha_matrix(

		Real aw0, Real aw1,

		Real bw0, Real bw1,

		const Vector3 &w_col );

	static void calc_raster_size(

		Pair2 &out_bounds,

		IntVector2 &out_raster_size,

		Matrix3 &out_raster_matrix,

		const Vector2 &resolution,

		const Pair2 &bounds,

		const Vector2 &dst_size );

	static void create_layers(

		LayerList &out_layers,

		const Matrix3 &matrix,

		const IntPair2 &dst_bounds,

		const Real step = 4.0 );

	static Real find_optimal_step(

		const Matrix3 &matrix,

		const IntPair2 &dst_bounds );

	static void add_premulted(

		const Layer &layer,

		Surface &src_surface,

		Surface &dst_surface );

	static void paint_cross(

		Surface &dst_surface,

		const Vector2 &point );

	static void print_layer(const Layer &layer, const std::string &prefix = std::string());

	static void print_layers(const LayerList &layers, const std::string &prefix = std::string());

};

#endif