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/**
* \class QgsScaleCalculator
* \brief Calculates scale for a given combination of canvas size, map extent,
* and monitor dpi.
*/
class QgsScaleCalculator
{
%TypeHeaderCode
#include <qgsscalecalculator.h>
%End
public:
/**
* Constructor
* @param dpi Monitor resolution in dots per inch
* @param mapUnits Units of the data on the map. Must match a value from the
* QGis::UnitType enum (Meters, Feet, Degrees)
*/
QgsScaleCalculator(int dpi = 0,
QGis::UnitType mapUnits = QGis::Meters);
//! Destructor
~QgsScaleCalculator();
/**
* Set the dpi to be used in scale calculations
* @param dpi Dots per inch of monitor resolution
*/
void setDpi(int dpi);
/**
* Accessor for dpi used in scale calculations
* @return int the dpi used for scale calculations.
*/
int dpi();
/**
* Set the map units
* @param mapUnits Units of the data on the map. Must match a value from the
*/
void setMapUnits(QGis::UnitType mapUnits);
/** Returns current map units */
QGis::UnitType mapUnits() const;
/**
* Calculate the scale
* @param mapExtent QgsRectangle containing the current map extent
* @param canvasWidth Width of the map canvas in pixel (physical) units
* @return scale of current map view
*/
double calculate(QgsRectangle &mapExtent, int canvasWidth);
/**
* Calculate the distance between to points in geographic coordinates.
* Used to calculate scale for map views with geographic (decimal degree)
* data.
* @param mapExtent QgsRectangle containing the current map extent
*/
double calculateGeographicDistance(QgsRectangle &mapExtent);
};
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