mirror of
https://github.com/qgis/QGIS.git
synced 2025-11-04 00:04:25 -05:00
63 lines
2.0 KiB
Plaintext
63 lines
2.0 KiB
Plaintext
%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 );
|
|
|
|
/** Takes a linestring and clips it to clipExtent
|
|
* @param curve the linestring
|
|
* @param clipExtent clipping bounds
|
|
* @return clipped line coordinates
|
|
*/
|
|
static QPolygonF clippedLine( const QgsCurve& curve, const QgsRectangle& clipExtent );
|
|
|
|
};
|