#ifndef BORDERS_EXTRACTOR_H

#define BORDERS_EXTRACTOR_H

#include "traster.h"

#include "runsmap.h"

#include "raster_edge_iterator.h"

namespace TRop

{

namespace borders

{

//*******************************************************************

//    Pixel Selector model

//*******************************************************************

/*!

  This class is just a stub for pixel selector classes.

  Pixel Selectors are objects used in raster borders recognition

  to interpret a raster's pixels and direct edge iterators.

\n\n

  The main purpose of this class is that of distinguishing pixels

  from their  values <\I>. Values are the actual entities recognized

  in the borders extraction process - adjacent pixels that are cast to

  the same value will be included in the same border.

\n\n

  For example, if we want to extract the borders of a fullcolor image

  that separate bright areas from dark ones, we can just have a pixel selector

  cast each pixel to the integer value 0 if the pixel's value is below the

  brigthness threshold, and 1 if above.

\n\n

  Also, pixel selectors tell whether pixels are to be intended as

  completely transparent (virtual pixels outside the raster boundaries are).

*/

template <typename pix,="" typename="" val=""></typename>

class pixel_selector

{

public:

	typedef Pix pixel_type; //!< The pixel type naming the selector

	typedef Val value_type; //!< A value type representing pixel contents.

							//!< Typically the pixel itself.

public:

	value_type value(const pixel_type &pix) const;

	bool equal(const pixel_type &a, const pixel_type &b) const

	{

		return value(a) == value(b);

	}

	value_type transparent() const;

	bool transparent(const pixel_type &pix) const

	{

		return value(pix) == transparent();

	}

	//! Returns whether a border point must be read or not (corners are always read).

	bool skip(const value_type &prevLeftValue, const value_type &leftValue) const { return true; }

};

//----------------------------------------------------------------------------------

enum RunType { _BORDER_LEFT = 0x20,

			   _BORDER_RIGHT = 0x10,

			   _HIERARCHY_INCREASE = 0x8,

			   _HIERARCHY_DECREASE = 0x4 };

//----------------------------------------------------------------------------------

/*!

  Reads the borders of the input raster, according to the specified selector.

  Outputs the borders by supplying a container reader with the raster edge iterators

  corresponding to border vertices. The runsmap used in the process can be

  returned in output.

*/

template <typename containerreader="" pixel,="" pixelselector,="" typename=""></typename>

void readBorders(const TRasterPT<pixel> &raster, const PixelSelector &selector,</pixel>

				 ContainerReader &reader, RunsMapP *rasterRunsMap = 0);

//=====================================================================================

template <typename containersreader="" mesh,="" pixelselector,="" typename=""></typename>

void readMeshes(const TRasterPT<typename pixelselector::pixel_type=""> &raster, const PixelSelector &selector,</typename>

				ContainersReader &meshesDataReader, RunsMapP *rasterRunsMap = 0);

}

} //namespace TRop::borders

#endif //BORDERS_EXTRACTOR_H

//=====================================================================================

#ifdef INCLUDE_HPP

#include "borders_extractor.hpp"

#endif //INCLUDE_HPP