QGIS API Documentation  3.21.0-Master (56b4176581)
Public Member Functions | Static Public Member Functions | List of all members
QgsMapToPixel Class Reference

Perform transforms between map coordinates and device coordinates. More...

#include <qgsmaptopixel.h>

Public Member Functions

 QgsMapToPixel ()
 Constructor. More...
 
 QgsMapToPixel (double mapUnitsPerPixel)
 Constructor. More...
 
 QgsMapToPixel (double mapUnitsPerPixel, double centerX, double centerY, int widthPixels, int heightPixels, double rotation)
 Constructor. More...
 
int mapHeight () const
 Returns current map height in pixels. More...
 
double mapRotation () const
 Returns current map rotation in degrees (clockwise) More...
 
double mapUnitsPerPixel () const
 Returns current map units per pixel. More...
 
int mapWidth () const
 Returns current map width in pixels The information is only known if setRotation was used. More...
 
bool operator!= (const QgsMapToPixel &other) const
 
bool operator== (const QgsMapToPixel &other) const
 
void setMapRotation (double degrees, double cx, double cy)
 Set map rotation in degrees (clockwise) More...
 
void setMapUnitsPerPixel (double mapUnitsPerPixel)
 Set map units per pixel. More...
 
void setParameters (double mapUnitsPerPixel, double centerX, double centerY, int widthPixels, int heightPixels, double rotation)
 Set parameters for use in transforming coordinates. More...
 
void setParameters (double mapUnitsPerPixel, double centerX, double centerY, int widthPixels, int heightPixels, double rotation, bool *ok)
 Set parameters for use in transforming coordinates. More...
 
QString showParameters () const
 String representation of the parameters used in the transform. More...
 
QgsPointXY toMapCoordinates (double x, double y) const
 Transform device coordinates to map (world) coordinates. More...
 
QgsPointXY toMapCoordinates (int x, int y) const
 Transform device coordinates to map (world) coordinates. More...
 
QgsPointXY toMapCoordinates (QPoint p) const
 Transform device coordinates to map (world) coordinates. More...
 
Q_DECL_DEPRECATED QgsPointXY toMapPoint (double x, double y) const
 Transform device coordinates to map (world) coordinates. More...
 
QTransform transform () const
 Returns a QTransform encapsulating the map to pixel conversion. More...
 
QgsPointXY transform (const QgsPointXY &p) const
 Transform the point p from map (world) coordinates to device coordinates. More...
 
void transform (QgsPointXY *p) const
 Transform the point p from map (world) coordinates to device coordinates in place. More...
 
QgsPointXY transform (qreal x, qreal y) const
 Transform the point specified by x,y from map (world) coordinates to device coordinates. More...
 
void transformInPlace (double &x, double &y) const
 Transforms device coordinates to map coordinates. More...
 
void transformInPlace (float &x, float &y) const
 Transforms device coordinates to map coordinates. More...
 
template<class T >
void transformInPlace (QVector< T > &x, QVector< T > &y) const
 Transform device coordinates to map coordinates. More...
 
double xCenter () const
 Returns the center x-coordinate for the transform. More...
 
double yCenter () const
 Returns the center y-coordinate for the transform. More...
 

Static Public Member Functions

static QgsMapToPixel fromScale (double scale, QgsUnitTypes::DistanceUnit mapUnits, double dpi=96)
 Returns a new QgsMapToPixel created using a specified scale and distance unit. More...
 

Detailed Description

Perform transforms between map coordinates and device coordinates.

This class can convert device coordinates to map coordinates and vice versa.

Definition at line 38 of file qgsmaptopixel.h.

Constructor & Destructor Documentation

◆ QgsMapToPixel() [1/3]

QgsMapToPixel::QgsMapToPixel ( double  mapUnitsPerPixel,
double  centerX,
double  centerY,
int  widthPixels,
int  heightPixels,
double  rotation 
)

Constructor.

Parameters
mapUnitsPerPixelMap units per pixel
centerXX coordinate of map center, in geographical units
centerYY coordinate of map center, in geographical units
widthPixelsOutput width, in pixels
heightPixelsOutput height, in pixels
rotationclockwise rotation in degrees
Since
QGIS 2.8

Definition at line 28 of file qgsmaptopixel.cpp.

◆ QgsMapToPixel() [2/3]

QgsMapToPixel::QgsMapToPixel ( double  mapUnitsPerPixel)

Constructor.

Parameters
mapUnitsPerPixelMap units per pixel

Definition at line 47 of file qgsmaptopixel.cpp.

◆ QgsMapToPixel() [3/3]

QgsMapToPixel::QgsMapToPixel ( )

Constructor.

Use setParameters to fill

Definition at line 64 of file qgsmaptopixel.cpp.

Member Function Documentation

◆ fromScale()

QgsMapToPixel QgsMapToPixel::fromScale ( double  scale,
QgsUnitTypes::DistanceUnit  mapUnits,
double  dpi = 96 
)
static

Returns a new QgsMapToPixel created using a specified scale and distance unit.

Parameters
scalemap scale denominator, e.g. 1000.0 for a 1:1000 map.
dpiscreen DPI
mapUnitsmap units
Returns
matching QgsMapToPixel
Since
QGIS 3.0

Definition at line 57 of file qgsmaptopixel.cpp.

◆ mapHeight()

int QgsMapToPixel::mapHeight ( ) const
inline

Returns current map height in pixels.

Since
QGIS 2.8

Definition at line 215 of file qgsmaptopixel.h.

◆ mapRotation()

double QgsMapToPixel::mapRotation ( ) const
inline

Returns current map rotation in degrees (clockwise)

Since
QGIS 2.8

Definition at line 230 of file qgsmaptopixel.h.

◆ mapUnitsPerPixel()

double QgsMapToPixel::mapUnitsPerPixel ( ) const
inline

Returns current map units per pixel.

Definition at line 202 of file qgsmaptopixel.h.

◆ mapWidth()

int QgsMapToPixel::mapWidth ( ) const
inline

Returns current map width in pixels The information is only known if setRotation was used.

Since
QGIS 2.8

Definition at line 209 of file qgsmaptopixel.h.

◆ operator!=()

bool QgsMapToPixel::operator!= ( const QgsMapToPixel other) const
inline

Definition at line 294 of file qgsmaptopixel.h.

◆ operator==()

bool QgsMapToPixel::operator== ( const QgsMapToPixel other) const
inline

Definition at line 282 of file qgsmaptopixel.h.

◆ setMapRotation()

void QgsMapToPixel::setMapRotation ( double  degrees,
double  cx,
double  cy 
)

Set map rotation in degrees (clockwise)

Parameters
degreesclockwise rotation in degrees
cxX ordinate of map center in geographical units
cyY ordinate of map center in geographical units
Since
QGIS 2.8

Definition at line 91 of file qgsmaptopixel.cpp.

◆ setMapUnitsPerPixel()

void QgsMapToPixel::setMapUnitsPerPixel ( double  mapUnitsPerPixel)

Set map units per pixel.

Parameters
mapUnitsPerPixelMap units per pixel

Definition at line 81 of file qgsmaptopixel.cpp.

◆ setParameters() [1/2]

void QgsMapToPixel::setParameters ( double  mapUnitsPerPixel,
double  centerX,
double  centerY,
int  widthPixels,
int  heightPixels,
double  rotation 
)

Set parameters for use in transforming coordinates.

Parameters
mapUnitsPerPixelMap units per pixel
centerXX coordinate of map center, in geographical units
centerYY coordinate of map center, in geographical units
widthPixelsOutput width, in pixels
heightPixelsOutput height, in pixels
rotationclockwise rotation in degrees
Note
if the specified parameters result in an invalid transform then no changes will be applied to the object
Since
QGIS 2.8

Definition at line 160 of file qgsmaptopixel.cpp.

◆ setParameters() [2/2]

void QgsMapToPixel::setParameters ( double  mapUnitsPerPixel,
double  centerX,
double  centerY,
int  widthPixels,
int  heightPixels,
double  rotation,
bool *  ok 
)

Set parameters for use in transforming coordinates.

Parameters
mapUnitsPerPixelMap units per pixel
centerXX coordinate of map center, in geographical units
centerYY coordinate of map center, in geographical units
widthPixelsOutput width, in pixels
heightPixelsOutput height, in pixels
rotationclockwise rotation in degrees
okwill be set to true if the specified parameters result in a valid transform, otherwise the changes are ignored and ok will be set to false.
Since
QGIS 3.20

Definition at line 116 of file qgsmaptopixel.cpp.

◆ showParameters()

QString QgsMapToPixel::showParameters ( ) const

String representation of the parameters used in the transform.

Definition at line 171 of file qgsmaptopixel.cpp.

◆ toMapCoordinates() [1/3]

QgsPointXY QgsMapToPixel::toMapCoordinates ( double  x,
double  y 
) const
inline

Transform device coordinates to map (world) coordinates.

Definition at line 165 of file qgsmaptopixel.h.

◆ toMapCoordinates() [2/3]

QgsPointXY QgsMapToPixel::toMapCoordinates ( int  x,
int  y 
) const
inline

Transform device coordinates to map (world) coordinates.

Definition at line 159 of file qgsmaptopixel.h.

◆ toMapCoordinates() [3/3]

QgsPointXY QgsMapToPixel::toMapCoordinates ( QPoint  p) const
inline

Transform device coordinates to map (world) coordinates.

Parameters
pPoint to be converted to map cooordinates
Returns
QgsPointXY in map coorndiates

Definition at line 180 of file qgsmaptopixel.h.

◆ toMapPoint()

Q_DECL_DEPRECATED QgsPointXY QgsMapToPixel::toMapPoint ( double  x,
double  y 
) const
inline

Transform device coordinates to map (world) coordinates.

Deprecated:
since QGIS 3.4 use toMapCoordinates instead

Definition at line 190 of file qgsmaptopixel.h.

◆ transform() [1/4]

QTransform QgsMapToPixel::transform ( ) const

Returns a QTransform encapsulating the map to pixel conversion.

Definition at line 181 of file qgsmaptopixel.cpp.

◆ transform() [2/4]

QgsPointXY QgsMapToPixel::transform ( const QgsPointXY p) const
inline

Transform the point p from map (world) coordinates to device coordinates.

Parameters
pPoint to transform
Returns
QgsPointXY in device coordinates

Definition at line 82 of file qgsmaptopixel.h.

◆ transform() [3/4]

void QgsMapToPixel::transform ( QgsPointXY p) const
inline

Transform the point p from map (world) coordinates to device coordinates in place.

Definition at line 93 of file qgsmaptopixel.h.

◆ transform() [4/4]

QgsPointXY QgsMapToPixel::transform ( qreal  x,
qreal  y 
) const
inline

Transform the point specified by x,y from map (world) coordinates to device coordinates.

Parameters
xx coordinate o point to transform
yy coordinate of point to transform
Returns
QgsPointXY in device coordinates

Definition at line 108 of file qgsmaptopixel.h.

◆ transformInPlace() [1/3]

void QgsMapToPixel::transformInPlace ( double &  x,
double &  y 
) const
inline

Transforms device coordinates to map coordinates.

Modifies the given coordinates in place. Intended as a fast way to do the transform.

Definition at line 119 of file qgsmaptopixel.h.

◆ transformInPlace() [2/3]

void QgsMapToPixel::transformInPlace ( float &  x,
float &  y 
) const
inline

Transforms device coordinates to map coordinates.

Modifies the given coordinates in place. Intended as a fast way to do the transform.

Note
Not available in Python bindings

Definition at line 133 of file qgsmaptopixel.h.

◆ transformInPlace() [3/3]

template<class T >
void QgsMapToPixel::transformInPlace ( QVector< T > &  x,
QVector< T > &  y 
) const
inline

Transform device coordinates to map coordinates.

Modifies the given coordinates in place. Intended as a fast way to do the transform.

Note
not available in Python bindings

Definition at line 150 of file qgsmaptopixel.h.

◆ xCenter()

double QgsMapToPixel::xCenter ( ) const
inline

Returns the center x-coordinate for the transform.

See also
yCenter()
Since
QGIS 3.0

Definition at line 273 of file qgsmaptopixel.h.

◆ yCenter()

double QgsMapToPixel::yCenter ( ) const
inline

Returns the center y-coordinate for the transform.

See also
xCenter()
Since
QGIS 3.0

Definition at line 280 of file qgsmaptopixel.h.


The documentation for this class was generated from the following files: