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%Feature ARM
class QgsClipper
{
%TypeHeaderCode
#include <qgsclipper.h>
%End
public:
// Coordinates of the rectangular box that we trim to.
//
// These are the limits for X11 screen coordinates. The actual
// values are +/-32767, but we allow a little bit of space for
// rounding errors.
// You may wonder why the clipping is done to these coordindates
// rather than the boundaries of the qgis canvas. Reasons include:
// - making the boundaries static const allows the compiler to
// optimise the code that uses these values more than if they changed
// for every call to the trim code.
// - clipping takes quite a bit of CPU effort, and the less that this is
// done the better. More stuff would have to be clipped if the
// boundaries were the qgis canvas (but this may be offset by
// having less to draw).
//
// The limit is set to 30,000 instead of 32768 because that things
// still go wrong.
static const double MAX_X;
static const double MIN_X;
static const double MAX_Y;
static const double MIN_Y;
//! A handy way to refer to the four boundaries
enum Boundary {XMax, XMin, YMax, YMin};
%If (!ARM)
/**
* Trims the given feature to a rectangular box. Returns the trimmed
* feature in x and y. The shapeOpen parameter determines whether
* the function treats the points as a closed shape (polygon), or as
* an open shape (linestring).
*
* @note not available in python bindings on android
*/
static void trimFeature( QVector<double>& x,
QVector<double>& y,
bool shapeOpen );
%End
static void trimPolygon( QPolygonF& pts, const QgsRectangle& clipRect );
/** Reads a polyline from WKB and clips it to clipExtent
@param wkb pointer to the start of the line wkb
@param clipExtent clipping bounds
@param line out: clipped line coordinates*/
static QgsConstWkbPtr clippedLineWKB( QgsConstWkbPtr& wkb, const QgsRectangle& clipExtent, QPolygonF& line );
};
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