Mercator projection that tries to render the resulting map in the same physical size on all devices. More...

#include <MercatorProjection.h>

Inheritance diagram for osmscout::MercatorProjection:

Public Member Functions
bool	CanBatch () const override

bool	GeoToPixel (const GeoCoord &coord, Vertex2D &pixel) const override
	Converts a geo coordinate to a pixel coordinate. More...

bool	IsLinearInterpolationEnabled () const

bool	IsValid () const override

bool	IsValidFor (const GeoCoord &coord) const override
	Return true if given coordinate is valid for this projection. More...

	MercatorProjection ()=default

	MercatorProjection (const MercatorProjection &)=default

	MercatorProjection (MercatorProjection &&)=default

bool	Move (double horizPixel, double vertPixel)

bool	MoveDown (double pixel)

bool	MoveLeft (double pixel)

bool	MoveRight (double pixel)

bool	MoveUp (double pixel)

MercatorProjection &	operator= (const MercatorProjection &)=default

MercatorProjection &	operator= (MercatorProjection &&)=default

bool	PixelToGeo (double x, double y, GeoCoord &coord) const override
	Converts a pixel coordinate to a geo coordinate. More...

bool	Set (const GeoCoord &coord, const Magnification &magnification, double dpi, size_t width, size_t height)

bool	Set (const GeoCoord &coord, const Magnification &magnification, size_t width, size_t height)

bool	Set (const GeoCoord &coord, double angle, const Magnification &magnification, double dpi, size_t width, size_t height)
	Setup projection parameters. More...

bool	Set (const GeoCoord &coord, double angle, const Magnification &magnification, size_t width, size_t height)

void	SetLinearInterpolationUsage (bool useLinearInterpolation)
	Switch to enable/disable linear interpolation of latitude to pixel computation. More...

	~MercatorProjection () override=default

Public Member Functions inherited from osmscout::Projection
bool	BoundingBoxToPixel (const GeoBox &boundingBox, ScreenBox &screenBox) const
	Converts a valid GeoBox to its on screen pixel coordinates. More...

double	ConvertPixelToWidth (double pixel) const
	Convert a width in pixel into the equivalent mm size based on the given DPI. More...

double	ConvertWidthToPixel (double width) const
	Convert a width in mm into the equivalent pixel size based on the given DPI. More...

double	GetAngle () const
	Returns the angle in radians ([0..2*PI[) of the display in relation to the north. More...

GeoCoord	GetCenter () const

GeoBox	GetDimensions () const

double	GetDPI () const
	Return the DPI as part of the projection. More...

size_t	GetHeight () const
	Returns the height of the screen. More...

Magnification	GetMagnification () const
	Return the magnification as part of the projection. More...

double	GetMeterInMM () const
	Returns the number of on screen millimeters for one meter on the ground. More...

double	GetMeterInPixel () const
	Returns the number of on screen pixel for one meter on the ground. More...

double	GetPixelSize () const
	Returns the size of a pixel in meter. More...

ScreenBox	GetScreenBox () const
	Return a ScreenBox instance for the screen. More...

size_t	GetWidth () const
	Returns the width of the screen. More...

Projection &	operator= (const Projection &)=default

Projection &	operator= (Projection &&)=default

	Projection ()=default

	Projection (const Projection &)=default

	Projection (Projection &&)=default

virtual	~Projection ()=default

Static Public Attributes
static const double	MaxLat = +85.0511

static const double	MaxLon = +180.0

static const double	MinLat = -85.0511

static const double	MinLon = -180.0

Protected Member Functions
void	GeoToPixel (const BatchTransformer &transformData) const override

Protected Attributes
double	angleCos =0.0

double	angleNegCos =0.0

double	angleNegSin =0.0

double	angleSin =0.0

double	latOffset =0.0
	Absolute and untransformed screen position of lat coordinate. More...

double	scale =1.0

double	scaledLatDeriv =0.0
	precalculated derivation of "latToYPixel" function in projection More...

double	scaleGradtorad =0.0
	Precalculated scale*Gradtorad. More...

bool	useLinearInterpolation =false
	switch to enable linear interpolation of latitude to pixel computation More...

bool	valid =false
	projection is valid More...

Protected Attributes inherited from osmscout::Projection
double	angle =0.0
	Display rotation angle in radians, canvas clockwise. More...

GeoBox	boundingBox
	Bounding box of the current projection on the ground. More...

GeoCoord	center
	Coordinate of the center of the displayed area. More...

double	dpi =0.0
	Screen DPI. More...

size_t	height =0
	Height of image. More...

Magnification	magnification
	Current magnification. More...

double	meterInMM =0.0
	Number of on screen millimeters for one meter on the ground. More...

double	meterInPixel =0.0
	Number of on screen pixel for one meter on the ground. More...

double	pixelSize =0.0
	Size of a pixel in meter. More...

size_t	width =0
	Width of image. More...

Detailed Description

Mercator projection that tries to render the resulting map in the same physical size on all devices.

If the physical DPI of the device is correctly given, objects on any device has the same size. Bigger devices will show "more" map thus.

Scale is calculated based on the assumption that the original OpenStreetMap tiles were designed for 96 DPI displays.

Constructor & Destructor Documentation

◆ MercatorProjection() [1/3]

osmscout::MercatorProjection::MercatorProjection ( )

default

◆ MercatorProjection() [2/3]

osmscout::MercatorProjection::MercatorProjection ( const MercatorProjection & )

default

◆ MercatorProjection() [3/3]

osmscout::MercatorProjection::MercatorProjection ( MercatorProjection && )

default

◆ ~MercatorProjection()

osmscout::MercatorProjection::~MercatorProjection ( )

overridedefault

Member Function Documentation

◆ CanBatch()

bool osmscout::MercatorProjection::CanBatch ( ) const

inlineoverridevirtual

Implements osmscout::Projection.

◆ GeoToPixel() [1/2]

void osmscout::MercatorProjection::GeoToPixel ( const BatchTransformer & transformData ) const

overrideprotectedvirtual

Implements osmscout::Projection.

◆ GeoToPixel() [2/2]

bool osmscout::MercatorProjection::GeoToPixel	(	const GeoCoord &	coord,
		Vertex2D &	pixel
	)		const

overridevirtual

Converts a geo coordinate to a pixel coordinate.

Return true on success, false if given coordinate is not valid for this projection.

Implements osmscout::Projection.

References osmscout::Projection::angle, angleNegCos, angleNegSin, osmscout::Projection::center, osmscout::GeoCoord::GetLat(), osmscout::GeoCoord::GetLon(), osmscout::gradtorad, osmscout::Projection::height, IsValidFor(), latOffset, MaxLat, MinLat, scale, scaledLatDeriv, scaleGradtorad, useLinearInterpolation, valid, and osmscout::Projection::width.

Referenced by osmscout::LockHandler::currentPosition(), Move(), osmscout::IconAnimation::paint(), osmscout::MapWidget::paint(), osmscout::PlaneMapRenderer::RenderMap(), osmscout::TiledRenderingHelper::RenderTiles(), and osmscout::MapWidget::screenPosition().

◆ IsLinearInterpolationEnabled()

bool osmscout::MercatorProjection::IsLinearInterpolationEnabled ( ) const

inline

◆ IsValid()

bool osmscout::MercatorProjection::IsValid ( ) const

inlineoverridevirtual

Implements osmscout::Projection.

Referenced by osmscout::MapWidget::paint().

◆ IsValidFor()

bool osmscout::MercatorProjection::IsValidFor ( const GeoCoord & coord ) const

inlineoverridevirtual

Return true if given coordinate is valid for this projection.

Implements osmscout::Projection.

References osmscout::GeoCoord::GetLat(), and osmscout::GeoCoord::GetLon().

Referenced by GeoToPixel(), PixelToGeo(), and Set().

◆ Move()

bool osmscout::MercatorProjection::Move	(	double	horizPixel,
		double	vertPixel
	)

References osmscout::Projection::angle, osmscout::Projection::center, osmscout::Projection::dpi, GeoToPixel(), osmscout::GeoCoord::GetLat(), osmscout::GeoCoord::GetLon(), osmscout::Vertex2D::GetX(), osmscout::Vertex2D::GetY(), osmscout::Projection::height, osmscout::Projection::magnification, PixelToGeo(), Set(), and osmscout::Projection::width.

Referenced by osmscout::MoveHandler::moveNow().

◆ MoveDown()

bool osmscout::MercatorProjection::MoveDown ( double pixel )

inline

◆ MoveLeft()

bool osmscout::MercatorProjection::MoveLeft ( double pixel )

inline

◆ MoveRight()

bool osmscout::MercatorProjection::MoveRight ( double pixel )

inline

◆ MoveUp()

bool osmscout::MercatorProjection::MoveUp ( double pixel )

inline

◆ operator=() [1/2]

MercatorProjection& osmscout::MercatorProjection::operator= ( const MercatorProjection & )

default

◆ operator=() [2/2]

MercatorProjection& osmscout::MercatorProjection::operator= ( MercatorProjection && )

default

◆ PixelToGeo()

bool osmscout::MercatorProjection::PixelToGeo	(	double	x,
		double	y,
		GeoCoord &	coord
	)		const

overridevirtual

Converts a pixel coordinate to a geo coordinate.

Return true on success, false if returned coordinate is not valid for this projection.

Implements osmscout::Projection.

References osmscout::Projection::angle, angleCos, angleSin, osmscout::Projection::center, osmscout::GeoCoord::GetLon(), osmscout::gradtorad, osmscout::Projection::height, IsValidFor(), latOffset, scale, scaleGradtorad, osmscout::GeoCoord::Set(), valid, and osmscout::Projection::width.

Referenced by osmscout::MapWidget::hoverMoveEvent(), Move(), osmscout::PlaneMapRenderer::RenderMap(), osmscout::TiledRenderingHelper::RenderTiles(), Set(), and osmscout::VehicleFollowHandler::vehiclePosition().

◆ Set() [1/4]

bool osmscout::MercatorProjection::Set	(	const GeoCoord &	coord,
		const Magnification &	magnification,
		double	dpi,
		size_t	width,
		size_t	height
	)

inline

◆ Set() [2/4]

bool osmscout::MercatorProjection::Set	(	const GeoCoord &	coord,
		const Magnification &	magnification,
		size_t	width,
		size_t	height
	)

inline

Referenced by osmscout::LockHandler::currentPosition(), osmscout::PlaneMapRenderer::DrawMap(), osmscout::MapWidget::getProjection(), osmscout::MapPainterOpenGL::MapPainterOpenGL(), Move(), osmscout::MoveHandler::moveNow(), osmscout::TiledMapRenderer::offlineTileRequest(), osmscout::TiledMapRenderer::onLoadJobFinished(), osmscout::PlaneMapRenderer::RenderMap(), osmscout::TiledRenderingHelper::RenderTiles(), osmscout::LookupModule::requestObjectsOnView(), osmscout::MapPainterOpenGL::SetCenter(), osmscout::MapPainterOpenGL::SetMagnification(), osmscout::PlaneMapRenderer::TriggerMapRendering(), and osmscout::VehicleFollowHandler::vehiclePosition().

◆ Set() [3/4]

bool osmscout::MercatorProjection::Set	(	const GeoCoord &	coord,
		double	angle,
		const Magnification &	magnification,
		double	dpi,
		size_t	width,
		size_t	height
	)

Setup projection parameters.

Return true on success, false if arguments are not valid for Mercator projection, projection parameters are unchanged in such case.

Angle is in radians ([0..2*PI[)

Note that coord (center) have to be valid coordinate in Mercator projection. But it is possible setup dimensions (width and height) that projection will cover area bigger than the one valid for Mercator projection. Bounding box is adjusted then to be valid for projection.

In code:

projection.GetDimensions(bbox); projection.GeoToPixel(bbox.GetMinCoord(),x,y)

may be x >= 0

◆ Set() [4/4]

bool osmscout::MercatorProjection::Set	(	const GeoCoord &	coord,
		double	angle,
		const Magnification &	magnification,
		size_t	width,
		size_t	height
	)

inline

◆ SetLinearInterpolationUsage()

void osmscout::MercatorProjection::SetLinearInterpolationUsage ( bool useLinearInterpolation )

inline

Switch to enable/disable linear interpolation of latitude to pixel computation.

It speedup GeoToPixel calculation with fractional error on small render area.

Referenced by osmscout::PlaneMapRenderer::DrawMap(), osmscout::TiledMapRenderer::onLoadJobFinished(), osmscout::LookupModule::requestObjectsOnView(), and osmscout::MapPainterOpenGL::SetMagnification().

Member Data Documentation

◆ angleCos

double osmscout::MercatorProjection::angleCos =0.0

protected

Referenced by PixelToGeo(), and Set().

◆ angleNegCos

double osmscout::MercatorProjection::angleNegCos =0.0

protected

Referenced by GeoToPixel(), and Set().

◆ angleNegSin

double osmscout::MercatorProjection::angleNegSin =0.0

protected

Referenced by GeoToPixel(), and Set().

◆ angleSin

double osmscout::MercatorProjection::angleSin =0.0

protected

Referenced by PixelToGeo(), and Set().

◆ latOffset

double osmscout::MercatorProjection::latOffset =0.0

protected

Absolute and untransformed screen position of lat coordinate.

Referenced by GeoToPixel(), PixelToGeo(), and Set().

◆ MaxLat

const double osmscout::MercatorProjection::MaxLat = +85.0511

static

Referenced by GeoToPixel(), and Set().

◆ MaxLon

const double osmscout::MercatorProjection::MaxLon = +180.0

static

Referenced by Set().

◆ MinLat

const double osmscout::MercatorProjection::MinLat = -85.0511

static

Referenced by GeoToPixel(), and Set().

◆ MinLon

const double osmscout::MercatorProjection::MinLon = -180.0

static

Referenced by Set().

◆ scale

double osmscout::MercatorProjection::scale =1.0

protected

Referenced by GeoToPixel(), PixelToGeo(), and Set().

◆ scaledLatDeriv

double osmscout::MercatorProjection::scaledLatDeriv =0.0

protected

precalculated derivation of "latToYPixel" function in projection

center scaled by gradtorad * scale

Referenced by GeoToPixel(), and Set().

◆ scaleGradtorad

double osmscout::MercatorProjection::scaleGradtorad =0.0

protected

Precalculated scale*Gradtorad.

Referenced by GeoToPixel(), PixelToGeo(), and Set().

◆ useLinearInterpolation

bool osmscout::MercatorProjection::useLinearInterpolation =false

protected

switch to enable linear interpolation of latitude to pixel computation

Referenced by GeoToPixel().

◆ valid

bool osmscout::MercatorProjection::valid =false

protected

projection is valid

Referenced by GeoToPixel(), PixelToGeo(), and Set().

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

Public Member Functions

Static Public Attributes

Protected Member Functions

Protected Attributes

Detailed Description

Constructor & Destructor Documentation

◆ MercatorProjection() [1/3]

◆ MercatorProjection() [2/3]

◆ MercatorProjection() [3/3]

◆ ~MercatorProjection()

Member Function Documentation

◆ CanBatch()

◆ GeoToPixel() [1/2]

◆ GeoToPixel() [2/2]

◆ IsLinearInterpolationEnabled()

◆ IsValid()

◆ IsValidFor()

◆ Move()

◆ MoveDown()

◆ MoveLeft()

◆ MoveRight()

◆ MoveUp()

◆ operator=() [1/2]

◆ operator=() [2/2]

◆ PixelToGeo()

◆ Set() [1/4]

◆ Set() [2/4]

◆ Set() [3/4]

◆ Set() [4/4]

◆ SetLinearInterpolationUsage()

Member Data Documentation

◆ angleCos

◆ angleNegCos

◆ angleNegSin

◆ angleSin

◆ latOffset

◆ MaxLat

◆ MaxLon

◆ MinLat

◆ MinLon

◆ scale

◆ scaledLatDeriv

◆ scaleGradtorad

◆ useLinearInterpolation

◆ valid