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