bool GeoDataLineString::operator==( const GeoDataLineString &other ) const
{
if ( !GeoDataGeometry::equals(other) ||
size() != other.size() ||
tessellate() != other.tessellate() ) {
return false;
}
const GeoDataLineStringPrivate* d = p();
const GeoDataLineStringPrivate* other_d = other.p();
QVector<GeoDataCoordinates>::const_iterator itCoords = d->m_vector.constBegin();
QVector<GeoDataCoordinates>::const_iterator otherItCoords = other_d->m_vector.constBegin();
QVector<GeoDataCoordinates>::const_iterator itEnd = d->m_vector.constEnd();
QVector<GeoDataCoordinates>::const_iterator otherItEnd = other_d->m_vector.constEnd();
for ( ; itCoords != itEnd && otherItCoords != otherItEnd; ++itCoords, ++otherItCoords ) {
if ( *itCoords != *otherItCoords ) {
return false;
}
}
Q_ASSERT ( itCoords == itEnd && otherItCoords == otherItEnd );
return true;
}
bool CylindricalProjectionPrivate::lineStringToPolygon( const GeoDataLineString &lineString,
const ViewportParams *viewport,
QVector<QPolygonF *> &polygons ) const
{
const TessellationFlags f = lineString.tessellationFlags();
qreal x = 0;
qreal y = 0;
qreal previousX = -1.0;
qreal previousY = -1.0;
int mirrorCount = 0;
qreal distance = repeatDistance( viewport );
polygons.append( new QPolygonF );
GeoDataLineString::ConstIterator itCoords = lineString.constBegin();
GeoDataLineString::ConstIterator itPreviousCoords = lineString.constBegin();
GeoDataLineString::ConstIterator itBegin = lineString.constBegin();
GeoDataLineString::ConstIterator itEnd = lineString.constEnd();
bool processingLastNode = false;
// We use a while loop to be able to cover linestrings as well as linear rings:
// Linear rings require to tessellate the path from the last node to the first node
// which isn't really convenient to achieve with a for loop ...
const bool isLong = lineString.size() > 10;
const int maximumDetail = levelForResolution(viewport->angularResolution());
// The first node of optimized linestrings has a non-zero detail value.
const bool hasDetail = itBegin->detail() != 0;
while ( itCoords != itEnd )
{
// Optimization for line strings with a big amount of nodes
bool skipNode = (hasDetail ? itCoords->detail() > maximumDetail
: itCoords != itBegin && isLong && !processingLastNode &&
!viewport->resolves( *itPreviousCoords, *itCoords ) );
if ( !skipNode ) {
Q_Q( const CylindricalProjection );
q->screenCoordinates( *itCoords, viewport, x, y );
// Initializing variables that store the values of the previous iteration
if ( !processingLastNode && itCoords == itBegin ) {
itPreviousCoords = itCoords;
previousX = x;
previousY = y;
}
// This if-clause contains the section that tessellates the line
// segments of a linestring. If you are about to learn how the code of
// this class works you can safely ignore this section for a start.
if ( lineString.tessellate() ) {
mirrorCount = tessellateLineSegment( *itPreviousCoords, previousX, previousY,
*itCoords, x, y,
polygons, viewport,
f, mirrorCount, distance );
}
else {
// special case for polys which cross dateline but have no Tesselation Flag
// the expected rendering is a screen coordinates straight line between
// points, but in projections with repeatX things are not smooth
mirrorCount = crossDateLine( *itPreviousCoords, *itCoords, x, y, polygons, mirrorCount, distance );
}
itPreviousCoords = itCoords;
previousX = x;
previousY = y;
}
// Here we modify the condition to be able to process the
// first node after the last node in a LinearRing.
if ( processingLastNode ) {
break;
}
++itCoords;
if ( itCoords == itEnd && lineString.isClosed() ) {
itCoords = itBegin;
processingLastNode = true;
}
}
GeoDataLatLonAltBox box = lineString.latLonAltBox();
// Closing e.g. in the Antarctica case.
// This code makes the assumption that
// - the first node is located at 180 E
// - and the last node is located at 180 W
// TODO: add a similar pattern in the crossDateLine() code.
/*
if( lineString.isClosed() && box.width() == 2*M_PI ) {
QPolygonF *poly = polygons.last();
if( box.containsPole( NorthPole ) ) {
qreal topMargin = 0.0;
qreal dummy = 0.0;
q_ptr->screenCoordinates(0.0, q_ptr->maxLat(), viewport, topMargin, dummy );
poly->push_back( QPointF( poly->last().x(), topMargin ) );
poly->push_back( QPointF( poly->first().x(), topMargin ) );
} else {
qreal bottomMargin = 0.0;
qreal dummy = 0.0;
q_ptr->screenCoordinates(0.0, q_ptr->minLat(), viewport, bottomMargin, dummy );
poly->push_back( QPointF( poly->last().x(), bottomMargin ) );
poly->push_back( QPointF( poly->first().x(), bottomMargin ) );
}
} */
repeatPolygons( viewport, polygons );
return polygons.isEmpty();
}