自学教程：C++ Get_xTo函数代码示例

//---------------------------------------------------------void CFlow_by_Slope::Set_Area(int x, int y){	double	Decay;	if( Get_Decay(x, y, Decay) )	{		int		i, ix, iy;		double	z, dzSum, dz[8];		for(i=0, dzSum=0.0, z=m_pDEM->asDouble(x, y); i<8; i++)		{			if( m_pDEM->is_InGrid(ix = Get_xTo(i, x), iy = Get_yTo(i, y)) && (dz[i] = z - m_pDEM->asDouble(ix, iy)) > 0.0 )			{				dzSum	+= (dz[i] = pow(dz[i] / Get_Length(i), 1.1));			}			else			{				dz[i]	= 0.0;			}		}		if( dzSum > 0.0 )		{			Decay	*= m_pFlow->asDouble(x, y) / dzSum;			for(i=0; i<8; i++)			{				if( dz[i] > 0.0 )				{					m_pFlow->Add_Value(Get_xTo(i, x), Get_yTo(i, y), Decay * dz[i]);				}			}		}	}}

//---------------------------------------------------------void CFlow_Parallel::Set_MFD(int x, int y){	int		i, ix, iy;	double	z, d, dzSum, dz[8];	//-----------------------------------------------------	for(i=0, dzSum=0.0, z=m_pDTM->asDouble(x, y); i<8; i++)	{		ix	= Get_xTo(i, x);		iy	= Get_yTo(i, y);		if( m_pDTM->is_InGrid(ix, iy) )		{			d	= z - m_pDTM->asDouble(ix, iy);		}		else		{			ix	= Get_xTo(i + 4, x);			iy	= Get_yTo(i + 4, y);			if( m_pDTM->is_InGrid(ix, iy) )			{				d	= m_pDTM->asDouble(ix, iy) - z;			}			else			{				d	= 0.0;			}		}		if( d > 0.0 )		{			dzSum	+= (dz[i] = pow(d / Get_Length(i), m_Converge));		}		else		{			dz[i]	= 0.0;		}	}	//-----------------------------------------------------	if( dzSum > 0.0 )	{		for(i=0; i<8; i++)		{			if( dz[i] > 0.0 )			{				Add_Fraction(x, y, i, dz[i] / dzSum);			}		}	}}

//---------------------------------------------------------void CFlow_Parallel::BRM_GetOrtho(int Dir, int x, int y, int ix[3], int iy[3], double nnei[6], int nexp[6]){	int		jx, jy, i,			i0	= (Dir + 2) % 8,			i4	= (Dir + 6) % 8;	double	Slope, Aspect;	for(i=0; i<3; i++)	{		jx		= ix[i];		jy		= iy[i];		Get_Gradient(jx, jy, Slope, Aspect);		nnei[i]	= M_RAD_TO_DEG * Slope;		nexp[i]	= (int)(M_RAD_TO_DEG * Aspect);	}	jx		= Get_xTo(i0,x);	jy		= Get_yTo(i0,y);	Get_Gradient(jx, jy, Slope, Aspect);	nnei[3]	= M_RAD_TO_DEG * Slope;	nexp[3]	= (int)(M_RAD_TO_DEG * Aspect);	jx		= Get_xTo(i4,x);	jy		= Get_yTo(i4,y);	Get_Gradient(jx, jy, Slope, Aspect);	nnei[5]	= M_RAD_TO_DEG * Slope;	nexp[5]	= (int)(M_RAD_TO_DEG * Aspect);	Get_Gradient(x, y, Slope, Aspect);	nnei[4]	= M_RAD_TO_DEG * Slope;	nexp[4]	= (int)(M_RAD_TO_DEG * Aspect);	//[jy][jx]) ????!!!!...;	for(i=0; i<6; i++)		if(nexp[i]<0)			nexp[i]	= nexp[4];	for(i=0; i<6; i++)	{		nexp[i]	+= BRM_idreh[Dir];		if(nexp[i]>360)			nexp[i]	-= 360;	}}

//---------------------------------------------------------void CChannelNetwork_Distance::Initialize_MFD(int x, int y){	const double	MFD_Convergence	= 1.1;	double	Flow[8], dz, zSum = 0.0, z = m_pDEM->asDouble(x, y);	if( m_pRoute )	{		for(int i=0, ix, iy; i<8; i++)		{			if( m_pDEM->is_InGrid(ix=Get_xTo(i, x), iy=Get_yTo(i, y)) && !m_pRoute->is_NoData(ix, iy) && (dz = z - m_pDEM->asDouble(ix, iy)) > 0.0 )			{				zSum	+= (Flow[i]	= pow(dz / Get_Length(i), MFD_Convergence));			}			else			{				Flow[i]	= 0.0;			}		}	}	if( zSum == 0.0 )	{		for(int i=0, ix, iy; i<8; i++)		{			if( m_pDEM->is_InGrid(ix=Get_xTo(i, x), iy=Get_yTo(i, y)) && (dz = z - m_pDEM->asDouble(ix, iy)) > 0.0 )			{				zSum	+= (Flow[i]	= pow(dz / Get_Length(i), MFD_Convergence));			}			else			{				Flow[i]	= 0.0;			}		}	}	if( zSum > 0.0 )	{		m_Flow[8].Set_Value(x, y, zSum);		for(int i=0; i<8; i++)		{			if( Flow[i] > 0.0 )			{				m_Flow[i].Set_Value(x, y, Flow[i] / zSum);			}		}	}}

//---------------------------------------------------------void CChannelNetwork::Set_Route_Standard(int x, int y){	int		i, ix, iy, iMin;	double	z, dz, dzMin;	z		= pDTM->asDouble(x,y);	iMin	= 0;	for(i=1; i<=8; i++)	{		ix		= Get_xTo(i,x);		iy		= Get_yTo(i,y);		if( !pDTM->is_InGrid(ix,iy) )		{			iMin	= i;			break;		}		else		{			dz		= (z - pDTM->asDouble(ix,iy)) / Get_Length(i);			if( iMin <= 0 || dzMin < dz )			{				iMin	= i;				dzMin	= dz;			}		}	}	pChannels->Set_Value(x,y, iMin );}

//---------------------------------------------------------void CD8_Flow_Analysis::Get_Direction(void){	Process_Set_Text(_TL("Flow Direction"));	m_pDir->Set_NoData_Value(-1);	CSG_Grid	*pCon	= Parameters("CONNECTION")	->asGrid();	if( pCon )	{		pCon->Assign(0.0);	}	for(int y=0; y<Get_NY() && Set_Progress(y); y++)	{		for(int x=0, i, ix, iy; x<Get_NX(); x++)		{			if( (i = m_pDEM->Get_Gradient_NeighborDir(x, y)) >= 0 && m_pDEM->is_InGrid(ix = Get_xTo(i, x), iy = Get_yTo(i, y)) )			{				m_pDir->Set_Value(x, y, i);				if( pCon )				{					pCon->Add_Value(ix, iy, 1);				}			}			else			{				m_pDir->Set_NoData(x, y);			}		}	}}

//---------------------------------------------------------double CExercise_14::Vectorise(int x, int y, CSG_Shape *pSegment){	int		Dir, ix, iy;	double	Length;	Length	= 0.0;	pSegment->Add_Point(Get_XMin() + x * Get_Cellsize(), Get_YMin() + y * Get_Cellsize());	if( (Dir = m_pDir->asInt(x, y)) >= 0 )	{		Length	= Get_Length(Dir);		ix		= Get_xTo(Dir, x);		iy		= Get_yTo(Dir, y);		switch( m_pChnl->asInt(ix, iy) )		{		case CHANNEL:			Length	+= Vectorise(ix, iy, pSegment);	// recursive function call...			break;		case MOUTH:			Length	+= Get_Length(Dir);			pSegment->Add_Point(Get_XMin() + ix * Get_Cellsize(), Get_YMin() + iy * Get_Cellsize());			break;		}	}	return( Length );}

//---------------------------------------------------------bool CPit_Eliminator::Dig_Channels(void){	bool	bPit;	int		x, y, i, ix, iy;	double	z;	for(y=0; y<Get_NY() && Set_Progress(y); y++)	{		for(x=0; x<Get_NX(); x++)		{			z		= pDTM->asDouble(x, y);			for(i=0, bPit=true; i<8 && bPit; i++)			{				ix		= Get_xTo(i, x);				iy		= Get_yTo(i, y);				if( !is_InGrid(ix, iy) || z > pDTM->asDouble(ix, iy) )				{					bPit	= false;				}			}			if( bPit )			{				Dig_Channel(x, y);			}		}	}	return( is_Progress() );}

//---------------------------------------------------------void CFlow_RecursiveUp::Get_Flow(int x, int y){	int		i, ix, iy, j;	double	jFlow;	if( !is_Locked(x,y) )	{		Lock_Set(x,y);		Init_Cell(x,y);		for(i=0, j=4; i<8; i++, j=(j+1)%8)		{			ix	= Get_xTo(i,x);			iy	= Get_yTo(i,y);			if( is_InGrid(ix,iy) )			{				jFlow	= Flow[iy][ix][j];				if( jFlow > 0 )				{					Get_Flow(ix,iy);					Add_Fraction(ix,iy,j,jFlow);				}			}		}	}}

//---------------------------------------------------------bool CChannelNetwork_Distance::Set_D8(int x, int y){	int	Direction;	if( !Get_D8(x, y, Direction) )	{		return( false );	}	int	ix = Get_xTo(Direction, x), iy = Get_yTo(Direction, y);	double	dz	= m_pDEM->asDouble(x, y) - m_pDEM->asDouble(ix, iy);	double	dx	= Get_Length(Direction);	m_pDistance->Set_Value(x, y, m_pDistance->asDouble(ix, iy) + sqrt(dz*dz + dx*dx));	m_pDistVert->Set_Value(x, y, m_pDistVert->asDouble(ix, iy) + dz);	m_pDistHorz->Set_Value(x, y, m_pDistHorz->asDouble(ix, iy) + dx);	if( m_pTime )	{		double	dt	= Get_Travel_Time(x, y, Direction);		m_pTime->Set_Value(x, y, m_pTime->asDouble(ix, iy) + dt);	}	if( m_pFields )	{		int	Crossed	= m_pFields->asDouble(ix, iy) == m_pFields->asDouble(x, y) ? 0 : 1;		m_pPasses->Set_Value(x, y, m_pPasses->asInt(ix, iy) + Crossed);	}	return( true );}

//---------------------------------------------------------inline double CChannelNetwork_Distance::Get_Travel_Time(int x, int y, int Direction){	int	ix = Get_xTo(Direction, x), iy = Get_yTo(Direction, y);	double	v, k, R, dz, dx;	dz	= m_pDEM->is_InGrid(ix, iy) ? m_pDEM->asDouble(x, y) - m_pDEM->asDouble(ix, iy) : 0.1;	dx	= Get_Length(Direction);//	k	= m_pFlow_K && !m_pFlow_K->is_NoData(x, y) ? m_pFlow_K->asDouble(x, y) : m_Flow_K;	k	= !m_pFlow_K || (m_pFlow_K->is_NoData(x, y) && m_pFlow_K->is_NoData(ix, iy)) ? m_Flow_K		: m_pFlow_K->is_NoData( x,  y) ? m_pFlow_K->asDouble(ix, iy)		: m_pFlow_K->is_NoData(ix, iy) ? m_pFlow_K->asDouble( x,  y)		: (m_pFlow_K->asDouble(x, y) + m_pFlow_K->asDouble(ix, iy)) / 2.0;//	R	= m_pFlow_R && !m_pFlow_R->is_NoData(x, y) ? m_pFlow_R->asDouble(x, y) : m_Flow_R;	R	= !m_pFlow_R || (m_pFlow_R->is_NoData(x, y) && m_pFlow_R->is_NoData(ix, iy)) ? m_Flow_R		: m_pFlow_R->is_NoData( x,  y) ? m_pFlow_R->asDouble(ix, iy)		: m_pFlow_R->is_NoData(ix, iy) ? m_pFlow_R->asDouble( x,  y)		: (m_pFlow_R->asDouble(x, y) + m_pFlow_R->asDouble(ix, iy)) / 2.0;	v	= k * pow(R, 2.0 / 3.0) * sqrt(dz / dx);	// [m / s], simplified Manning equation	return( dx / (v * 3600.0) );	// return travel time in hours}

//---------------------------------------------------------void CHillslope_Evolution_FTCS::Set_Diffusion(double dFactor){	int	iStep	= Parameters("NEIGHBOURS")->asInt() == 1 ? 1 : 2;	m_pDEM_Old->Assign(m_pDEM);	#pragma omp parallel for	for(int y=0; y<Get_NY(); y++)	{		for(int x=0; x<Get_NX(); x++)		{			if( !m_pDEM_Old->is_NoData(x, y) )			{				double	z	= m_pDEM_Old->asDouble(x, y);				double	dz	= 0.0;				for(int i=0; i<8; i+=iStep)				{					int	ix	= Get_xTo(i, x);					int	iy	= Get_yTo(i, y);					if( m_pDEM_Old->is_InGrid(ix, iy) )					{						dz	+= (m_pDEM_Old->asDouble(ix, iy) - z) / Get_UnitLength(i);					}				}				m_pDEM->Add_Value(x, y, dFactor * dz);			}		}	}}

//---------------------------------------------------------void CChannelNetwork_Distance::Initialize_D8(int x, int y){	int		i, iMax, iRoute;	double	z, dz, dzMax, dzRoute;	for(i=0, iMax=-1, dzMax=0.0, iRoute=-1, dzRoute=0.0, z=m_pDEM->asDouble(x, y); i<8; i++)	{		int	ix	= Get_xTo(i, x);		int	iy	= Get_yTo(i, y);		if( is_InGrid(ix, iy) && (dz = (z - m_pDEM->asDouble(ix, iy)) / Get_Length(i)) > 0.0 )		{			if( dz > dzMax )			{				iMax	= i;				dzMax	= dz;			}			if( m_pRoute && !m_pRoute->is_NoData(ix, iy) && dz > dzRoute )			{				iRoute	= i;				dzRoute	= dz;			}		}	}	m_Dir.Set_Value(x, y, iRoute >= 0 ? iRoute : iMax);}

//---------------------------------------------------------void CFlow_RecursiveUp::Set_MFD(int x, int y){	int		i, ix, iy;	double	z, d, *dz, dzSum;	z		= pDTM->asDouble(x,y);	dz		= Flow[y][x];	dzSum	= 0;	for(i=0; i<8; i++)	{		ix	= Get_xTo(i,x);		iy	= Get_yTo(i,y);		if( is_InGrid(ix,iy) )		{			d	= z - pDTM->asDouble(ix,iy);			if( d > 0 )				dzSum	+= dz[i]	= pow(d / Get_Length(i), MFD_Converge);		}	}	if( dzSum )	{		for(i=0; i<8; i++)			if( dz[i] > 0 )				dz[i]	/= dzSum;	}}

//---------------------------------------------------------bool CKinWav_D8::Gauges_Initialise(void){	if( m_pGauges_Flow != NULL )	{		if( m_pGauges == NULL )		{			DataObject_Add(m_pGauges = SG_Create_Shapes(SHAPE_TYPE_Point, _TL("Gauges")));			Parameters("GAUGES")->Set_Value(m_pGauges);			m_pGauges->Add_Field(_TL("ID"), SG_DATATYPE_Int);			for(int y=0; y<Get_NY() && Set_Progress(y); y++)			{				for(int x=0; x<Get_NX(); x++)				{					bool	bBorder	= false;					bool	bLowest	= true;					for(int i=0; i<8; i++)					{						int	ix	= Get_xTo(i, x);						int	iy	= Get_yTo(i, y);						if( !m_pDEM->is_InGrid(ix, iy) )						{							bBorder	= true;						}						else if( m_pDEM->asDouble(ix, iy) < m_pDEM->asDouble(x, y) )						{							bLowest	= false;						}					}					if( bLowest && bBorder )					{						CSG_Shape	*pGauge	= m_pGauges->Add_Shape();						pGauge->Add_Point(Get_System()->Get_Grid_to_World(x, y));						pGauge->Set_Value(0, m_pGauges->Get_Count() + 1);					}				}			}		}		m_pGauges_Flow->Destroy();		m_pGauges_Flow->Set_Name(_TL("Outlet Hydrographs"));		m_pGauges_Flow->Add_Field("TIME", SG_DATATYPE_Double);		for(int i=0; i<m_pGauges->Get_Count(); i++)		{			m_pGauges_Flow->Add_Field(CSG_String::Format(SG_T("GAUGE_%02d"), i + 1), SG_DATATYPE_Double);		}		return( true );	}	return( false );}

//---------------------------------------------------------void CFlow_Distance::Set_Length_MFD(int x, int y){	int		i, ix, iy;	double	z, d, dzSum, dz[8];	if( m_pDTM->is_InGrid(x, y) )	{		z		= m_pDTM->asDouble(x, y);		dzSum	= 0.0;		for(i=0; i<8; i++)		{			ix		= Get_xTo(i, x);			iy		= Get_yTo(i, y);			if( m_pDTM->is_InGrid(ix, iy) && (d = z - m_pDTM->asDouble(ix, iy)) > 0.0 )			{				dz[i]	= pow(d / Get_Length(i), m_Converge);				dzSum	+= dz[i];			}			else			{				dz[i]	= 0.0;			}		}		if( dzSum > 0.0 )		{			d	 = m_pLength->asDouble(x, y);			for(i=0; i<8; i++)			{				if( dz[i] > 0.0 )				{					ix		= Get_xTo(i, x);					iy		= Get_yTo(i, y);					dz[i]	/= dzSum;					m_pLength->Add_Value(ix, iy, dz[i] * (d + Get_Length(i)));					m_pWeight->Add_Value(ix, iy, dz[i]);				}			}		}	}}

//---------------------------------------------------------void CCellBalance::Set_MFD(int x, int y, double Weight){	const double	MFD_Converge	= 1.1;	int		i, ix, iy;	double	z, d, dzSum, dz[8];	z		= m_pDEM->asDouble(x, y);	dzSum	= 0.0;	for(i=0; i<8; i++)	{		ix		= Get_xTo(i, x);		iy		= Get_yTo(i, y);		if( m_pDEM->is_InGrid(ix, iy) && (d = z - m_pDEM->asDouble(ix, iy)) > 0.0 )		{			dz[i]	= pow(d / Get_Length(i), MFD_Converge);			dzSum	+= dz[i];		}		else		{			dz[i]	= 0.0;		}	}	if( dzSum > 0.0 )	{		d		= Weight / dzSum;		for(i=0; i<8; i++)		{			if( dz[i] > 0.0 )			{				ix		= Get_xTo(i, x);				iy		= Get_yTo(i, y);				m_pBalance->Add_Value(ix, iy, dz[i] * d);			}		}	}}

//---------------------------------------------------------int CD8_Flow_Analysis::Get_Basin(int x, int y){	int		i, Basin	= m_pBasins->asInt(x, y);	if( Basin <= 0 && (i = m_pDir->asInt(x, y)) >= 0 && (Basin = Get_Basin(Get_xTo(i, x), Get_yTo(i, y))) > 0 )	{		m_pBasins->Set_Value(x, y, Basin);	}	return( Basin );}

//---------------------------------------------------------inline double CChannelNetwork_Distance::Get_Travel_Time(int x, int y, int i){	double	dz	= m_pDEM->asDouble(Get_xTo(i, x), Get_yTo(i, y)) - m_pDEM->asDouble(x, y);	double	dx	= Get_Length(i);	double	k	= m_pFlow_K && !m_pFlow_K->is_NoData(x, y) ? m_pFlow_K->asDouble(x, y) : m_Flow_K;	double	R	= m_pFlow_R && !m_pFlow_R->is_NoData(x, y) ? m_pFlow_R->asDouble(x, y) : m_Flow_R;	double	v	= k * pow(R, 2.0 / 3.0) * sqrt(dz / dx);	// [m / s], simplified Manning equation	return( dx / (v * 3600.0) );	// return travel time in hours}