/**********************************************************
 * Version $Id: snap_points_to_grid.cpp 911 2011-02-14 16:38:15Z reklov_w $
 *********************************************************/

///////////////////////////////////////////////////////////
//                                                       //
//                         SAGA                          //
//                                                       //
//      System for Automated Geoscientific Analyses      //
//                                                       //
//                    Module Library:                    //
//                     shapes_points                     //
//                                                       //
//-------------------------------------------------------//
//                                                       //
//                snap_points_to_grid.cpp                //
//                                                       //
//                 Copyright (C) 2012 by                 //
//                      Olaf Conrad                      //
//                                                       //
//-------------------------------------------------------//
//                                                       //
// This file is part of 'SAGA - System for Automated     //
// Geoscientific Analyses'. SAGA is free software; you   //
// can redistribute it and/or modify it under the terms  //
// of the GNU General Public License as published by the //
// Free Software Foundation; version 2 of the License.   //
//                                                       //
// SAGA is distributed in the hope that it will be       //
// useful, but WITHOUT ANY WARRANTY; without even the    //
// implied warranty of MERCHANTABILITY or FITNESS FOR A  //
// PARTICULAR PURPOSE. See the GNU General Public        //
// License for more details.                             //
//                                                       //
// You should have received a copy of the GNU General    //
// Public License along with this program; if not,       //
// write to the Free Software Foundation, Inc.,          //
// 51 Franklin Street, 5th Floor, Boston, MA 02110-1301, //
// USA.                                                  //
//                                                       //
//-------------------------------------------------------//
//                                                       //
//    e-mail:     oconrad@saga-gis.org                   //
//                                                       //
//    contact:    Olaf Conrad                            //
//                Institute of Geography                 //
//                University of Hamburg                  //
//                Germany                                //
//                                                       //
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//														 //
//														 //
//														 //
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//---------------------------------------------------------
#include "snap_points_to_grid.h"


///////////////////////////////////////////////////////////
//														 //
//														 //
//														 //
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//---------------------------------------------------------
CSnap_Points_to_Grid::CSnap_Points_to_Grid(void)
{
	//-----------------------------------------------------
	Set_Name		(_TL("Snap Points to Grid"));

	Set_Author		(SG_T("O.Conrad (c) 2012"));

	Set_Description	(_TW(
		"Moves all points to grid cell positions that have the highest or"
		"lowest value respectively within the given search distance around "
		"each point."
	));

	//-----------------------------------------------------
	Parameters.Add_Shapes(
		NULL	, "INPUT"		, _TL("Points"),
		_TL(""),
		PARAMETER_INPUT, SHAPE_TYPE_Point
	);

	Parameters.Add_Grid(
		NULL	, "GRID"		, _TL("Grid"),
		_TL(""),
		PARAMETER_INPUT
	);

	Parameters.Add_Shapes(
		NULL	, "OUTPUT"		, _TL("Result"),
		_TL(""),
		PARAMETER_OUTPUT_OPTIONAL, SHAPE_TYPE_Point
	);

	Parameters.Add_Shapes(
		NULL	, "MOVES"		, _TL("Moves"),
		_TL(""),
		PARAMETER_OUTPUT_OPTIONAL, SHAPE_TYPE_Line
	);

	Parameters.Add_Value(
		NULL	, "DISTANCE"	, _TL("Search Distance (Map Units)"),
		_TL(""),
		PARAMETER_TYPE_Double, 0.0, 0.0, true
	);

	Parameters.Add_Choice(
		NULL	, "SHAPE"		, _TL("Search Shape"),
		_TL(""),
		CSG_String::Format(SG_T("%s|%s|"),
			_TL("circle"),
			_TL("square")
		), 0
	);

	Parameters.Add_Choice(
		NULL	, "EXTREME"		, _TL("Extreme"),
		_TL(""),
		CSG_String::Format(SG_T("%s|%s|"),
			_TL("minimum"),
			_TL("maximum")
		), 1
	);
}


///////////////////////////////////////////////////////////
//														 //
///////////////////////////////////////////////////////////

//---------------------------------------------------------
bool CSnap_Points_to_Grid::On_Execute(void)
{
	double		Distance, Sign;
	CSG_Shapes	*pInput, *pPoints, *pMoves;
	CSG_Grid	*pGrid;

	//-----------------------------------------------------
	pInput		= Parameters("INPUT"   )->asShapes();
	pPoints		= Parameters("OUTPUT"  )->asShapes();
	pGrid		= Parameters("GRID"    )->asGrid();
	pMoves		= Parameters("MOVES"   )->asShapes();
	Distance	= Parameters("DISTANCE")->asDouble() / Get_Cellsize();
	Sign		= Parameters("EXTREME" )->asInt() == 1 ? 1 : -1;

	//-----------------------------------------------------
	if( !pInput->is_Valid() )
	{
		Error_Set(_TL("invalid points layer"));

		return( false );
	}

	if( pInput->Get_Extent().Intersects(pGrid->Get_Extent()) == INTERSECTION_None )
	{
		Error_Set(_TL("points layer and grid do not intersect at all"));

		return( false );
	}

	if( Distance < 0.5 )
	{
		if( !Error_Set(_TL("search distance is less than half of grid cell size")) )	// ignore
		{
			return( false );
		}
	}

	//-----------------------------------------------------
	if( pPoints && pPoints != pInput )
	{
		pPoints->Create(*pInput);
	}
	else
	{
		Parameters("RESULT")->Set_Value(pPoints	= pInput);
	}

	pPoints->Set_Name(CSG_String::Format(SG_T("%s [%s: %s]"), pInput->Get_Name(), _TL("snapped"), pGrid->Get_Name()));

	if( pMoves )
	{
		pMoves->Create(SHAPE_TYPE_Line, CSG_String::Format(SG_T("%s [%s: %s]"), pInput->Get_Name(), _TL("snap move"), pGrid->Get_Name()), pPoints);
	}

	//-----------------------------------------------------
	CSG_Grid_Cell_Addressor	Search;

	Search.Set_Radius(Distance, Parameters("SHAPE")->asInt() == 1);

	//-----------------------------------------------------
	for(int iPoint=0; iPoint<pPoints->Get_Count() && Set_Progress(iPoint, pPoints->Get_Count()); iPoint++)
	{
		CSG_Shape	*pPoint		= pPoints->Get_Shape(iPoint);
		TSG_Point	Point		= pPoint->Get_Point(0);

		int		x		= Get_System()->Get_xWorld_to_Grid(Point.x);
		int		y		= Get_System()->Get_yWorld_to_Grid(Point.y);
		int		iMax	= -1;
		double	dMax;

		for(int i=0; i<Search.Get_Count(); i++)
		{
			int	ix	= Search.Get_X(i, x);
			int	iy	= Search.Get_Y(i, y);

			if( pGrid->is_InGrid(ix, iy) )
			{
				if( iMax < 0 || dMax < Sign * pGrid->asDouble(ix, iy) )
				{
					iMax	= i;
					dMax	= Sign * pGrid->asDouble(ix, iy);
				}
			}
		}

		//-------------------------------------------------
		if( iMax >= 0 )
		{
			TSG_Point	snap_Point	= pGrid->Get_System().Get_Grid_to_World(Search.Get_X(iMax, x), Search.Get_Y(iMax, y));

			if( SG_Get_Distance(Point, snap_Point) > 0.0 )
			{
				pPoint->Set_Point(snap_Point, 0);

				if( pMoves )
				{
					CSG_Shape	*pMove	= pMoves->Add_Shape(pPoint, SHAPE_COPY_ATTR);

					pMove->Add_Point(Point);
					pMove->Add_Point(snap_Point);
				}
			}
		}
	}

	//-----------------------------------------------------
	return( true );
}


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