//---------------------------------------------------------
void CSG_Shape_Points::_Update_Extent(void)
{
if( m_bUpdate )
{
bool bFirst;
int iPart;
for(iPart=0, bFirst=true; iPart<m_nParts; iPart++)
{
CSG_Shape_Part *pPart = m_pParts[iPart];
if( pPart->Get_Count() > 0 )
{
if( bFirst )
{
bFirst = false;
m_Extent = pPart->Get_Extent();
m_ZMin = pPart->Get_ZMin();
m_ZMax = pPart->Get_ZMax();
m_MMin = pPart->Get_MMin();
m_MMax = pPart->Get_MMax();
}
else
{
m_Extent.Union(pPart->Get_Extent());
if( m_ZMin > pPart->Get_ZMin() ) m_ZMin = pPart->Get_ZMin();
if( m_ZMax < pPart->Get_ZMax() ) m_ZMax = pPart->Get_ZMax();
if( m_MMin > pPart->Get_MMin() ) m_MMin = pPart->Get_MMin();
if( m_MMax < pPart->Get_MMax() ) m_MMax = pPart->Get_MMax();
}
}
}
m_bUpdate = false;
}
}
//---------------------------------------------------------
TSG_Intersection CSG_Shape_Line::On_Intersects(TSG_Rect Region)
{
// called if polygon's bounding box contains or overlaps with region.
// now let's figure out how region intersects with polygon itself
//-----------------------------------------------------
for(int iPart=0; iPart<m_nParts; iPart++)
{
CSG_Shape_Part *pPart = m_pParts[iPart];
switch( pPart->Get_Extent().Intersects(Region) )
{
case INTERSECTION_None: // region and line part are distinct
break;
case INTERSECTION_Identical: // region contains line part
case INTERSECTION_Contained:
return( Get_Extent().Intersects(Region) );
case INTERSECTION_Contains:
case INTERSECTION_Overlaps: // region overlaps with line part's extent, now let's look at the line part itself!
if( pPart->Get_Count() > 1 )
{
TSG_Point *pa, *pb, c;
pb = pPart->m_Points;
pa = pb + 1;
for(int iPoint=1; iPoint<pPart->Get_Count(); iPoint++, pb=pa++)
{
if( SG_Get_Crossing_InRegion(c, *pa, *pb, Region) )
{
return( INTERSECTION_Overlaps );
}
}
}
break;
}
}
//-----------------------------------------------------
TSG_Point p = Get_Point(0, 0);
if( Region.xMin <= p.x && p.x <= Region.xMax
&& Region.yMin <= p.y && p.y <= Region.yMax )
{
return( INTERSECTION_Contained );
}
return( INTERSECTION_None );
}
//---------------------------------------------------------
bool CPolygon_Transect::On_Execute(void)
{
CSG_Table *pTransect_Result;
CSG_Shapes *pTheme, *pTransect;
CSG_Shape_Line *pLine;
CSG_Shape_Polygon *pTheme_Shape;
int Theme_Field;
pTransect = Parameters("TRANSECT")->asShapes();
pTheme = Parameters("THEME")->asShapes();
pTransect_Result = Parameters("TRANSECT_RESULT")->asTable();
Theme_Field = Parameters("THEME_FIELD")->asInt();
//-----------------------------------------------------
// Check for valid parameter settings...
//-----------------------------------------------------
if (pTheme->Get_Type() != SHAPE_TYPE_Polygon){
Error_Set(CSG_String("[THEME] is not a polygon file"));
return(false);
}
if (pTransect->Get_Type() != SHAPE_TYPE_Line){
Error_Set(CSG_String("[TRANSECT] is not a line shapefile"));
return(false);
}
if (pTheme->Get_Count() ==0 || pTransect->Get_Count()==0)
{
Error_Set(CSG_String("[TRANSECT] or [THEME] is empty"));
return(false);
}
if (!(pTheme->Get_Extent().Intersects(pTransect->Get_Extent())))
{
Error_Set(CSG_String("[TRANSECT] and [THEME] do not intersect"));
return(false);
}
const int LINE_ID = pTransect_Result->Get_Field_Count();
pTransect_Result->Add_Field(SG_T("line_id"), SG_DATATYPE_Int);
const int START = pTransect_Result->Get_Field_Count();
pTransect_Result->Add_Field(SG_T("start"), SG_DATATYPE_Double);
const int END = pTransect_Result->Get_Field_Count();
pTransect_Result->Add_Field(SG_T("end"), SG_DATATYPE_Double);
const int POLY_ID = pTransect_Result->Get_Field_Count();
pTransect_Result->Add_Field(SG_T("poly_id"), SG_DATATYPE_Int);
const int FIELD = pTransect_Result->Get_Field_Count();
pTransect_Result->Add_Field(SG_T("field"), pTheme->Get_Field_Type(Theme_Field));
// Short description of the algorithm:
// For every line it is checked whether it crosses a polygon. If it does,
// the points where it crosses are recorded in the map LineBorders, with
// the polygon_id as key.
for (int iLine=0; iLine<pTransect->Get_Count() && Set_Progress(iLine, pTransect->Get_Count());
iLine++)
{
pLine =(CSG_Shape_Line *) pTransect->Get_Shape(iLine);
for (int iLinePart=0;iLinePart<pLine->Get_Part_Count();iLinePart++)
{
CSG_Shape_Part *pLinePart =pLine->Get_Part(iLinePart);
CSG_Rect LinePartExtent = pLinePart->Get_Extent();
map<int,list<double> > LineBorders;
for (int iShape=0; iShape<pTheme->Get_Count();iShape++)
{
pTheme_Shape = (CSG_Shape_Polygon *) pTheme->Get_Shape(iShape);
if (pLinePart->Get_Extent().Intersects(pTheme_Shape->Get_Extent())>0)
{
for (int iPart=0; iPart<pTheme_Shape->Get_Part_Count(); iPart++)
{
CSG_Shape_Polygon_Part *pPart = (CSG_Shape_Polygon_Part *) pTheme_Shape->Get_Part(iPart);
if (pPart->Contains(pLinePart->Get_Point(0)))
LineBorders[iShape].push_back(0);
if (pPart->Contains(pLinePart->Get_Point(pLinePart->Get_Count())))
LineBorders[iShape].push_back(pLine->Get_Length(iLinePart));
for (int iPoint=0; iPoint<pPart->Get_Count();iPoint++)
{
int iPoint2 = (iPoint!=pPart->Get_Count()-1)?iPoint+1:0;
TSG_Point Crossing;
double Length=0;
for (int iLinePartPoint=0; iLinePartPoint<pLinePart->Get_Count(); iLinePartPoint++)
{
if (SG_Get_Crossing(Crossing,pPart->Get_Point(iPoint),pPart->Get_Point(iPoint2),
pLinePart->Get_Point(iLinePartPoint), pLinePart->Get_Point(iLinePartPoint+1)))
{
LineBorders[iShape].push_back(Length+SG_Get_Distance(Crossing, pLinePart->Get_Point(iLinePartPoint)));
}
Length+=SG_Get_Distance(pLinePart->Get_Point(iLinePartPoint), pLinePart->Get_Point(iLinePartPoint+1));
}
}
}
}
}
// convert LineBorders to the result table
// the table contains the lineids and the distance to the origin of the line,
// and it is sorted by lineid, polygonid
CSG_Table_Record *pRecord;
for (map<int,list<double> >::iterator shapeit=LineBorders.begin();shapeit!=LineBorders.end();++shapeit)
{
//shapeit->second.sort();
bool start=1;
for (list<double>::iterator i=shapeit->second.begin(); i!=shapeit->second.end();++i)
{
if (start){
pRecord =pTransect_Result->Add_Record();
pRecord->Set_Value(LINE_ID, iLine);
pRecord->Set_Value(START, *i);
pRecord->Set_Value(POLY_ID, shapeit->first);
CSG_Table_Record *pTheme_Record =pTheme->Get_Shape(shapeit->first) ;
if(pTheme->Get_Field_Type(Theme_Field)== SG_DATATYPE_String )
pRecord->Set_Value(FIELD, pTheme_Record->asString(Theme_Field));
else
pRecord->Set_Value(FIELD, pTheme_Record->asDouble(Theme_Field));
start = 0;
}
else
{
pRecord->Set_Value(END, *i);
start=1;
}
}
}
}
}
return( true );
}