Responsible for rendering vector field data. More...

#include <qgsvectorfieldengine.h>

Public Member Functions
	QgsVectorFieldEngine (const QgsVectorFieldEngine &)=delete
	QgsVectorFieldEngine (double datasetMagMaximumValue, double datasetMagMinimumValue, const QgsVectorFieldSettings &settings, QgsRenderContext &context, QSize size)
	Ctor.
	~QgsVectorFieldEngine ()
	Dtor.
void	drawGlyph (const QgsPointXY &lineStart, double xVal, double yVal, double magnitude)
	Draws a single glyph at lineStart, in painter coordinates, using the symbology of the settings the engine was constructed with.
void	drawStreamlines (std::unique_ptr< QgsVectorFieldValueSource > source, QgsRasterBlockFeedback *feedback=nullptr)
	Integrates and draws streamlines over the whole rendered extent, sampling the vector field from source, which the engine takes ownership of.
void	drawTraces (std::unique_ptr< QgsVectorFieldValueSource > source)
	Seeds particles over the whole rendered extent, moves them one time step and draws their traces, sampling the vector field from source, which the engine takes ownership of.
QgsVectorFieldEngine &	operator= (const QgsVectorFieldEngine &)=delete

Detailed Description

Responsible for rendering vector field data.

Note: Not available in Python bindings

Since: QGIS 4.4

Definition at line 44 of file qgsvectorfieldengine.h.

Constructor & Destructor Documentation

◆ QgsVectorFieldEngine() [1/2]

QgsVectorFieldEngine::QgsVectorFieldEngine	(	double	datasetMagMaximumValue,
		double	datasetMagMinimumValue,
		const QgsVectorFieldSettings &	settings,
		QgsRenderContext &	context,
		QSize	size )

Ctor.

Definition at line 30 of file qgsvectorfieldengine.cpp.

◆ ~QgsVectorFieldEngine()

QgsVectorFieldEngine::~QgsVectorFieldEngine ( )

default

Dtor.

◆ QgsVectorFieldEngine() [2/2]

QgsVectorFieldEngine::QgsVectorFieldEngine ( const QgsVectorFieldEngine & )

delete

Member Function Documentation

◆ drawGlyph()

void QgsVectorFieldEngine::drawGlyph	(	const QgsPointXY &	lineStart,
		double	xVal,
		double	yVal,
		double	magnitude )

Draws a single glyph at lineStart, in painter coordinates, using the symbology of the settings the engine was constructed with.

Does nothing for the symbologies which are not drawn glyph by glyph, see drawStreamlines() and drawTraces().

Definition at line 69 of file qgsvectorfieldengine.cpp.

◆ drawStreamlines()

void QgsVectorFieldEngine::drawStreamlines	(	std::unique_ptr< QgsVectorFieldValueSource >	source,
		QgsRasterBlockFeedback *	feedback = nullptr )

Integrates and draws streamlines over the whole rendered extent, sampling the vector field from source, which the engine takes ownership of.

feedback is used to interrupt the rendering of the color ramp background image.

Definition at line 86 of file qgsvectorfieldengine.cpp.

◆ drawTraces()

void QgsVectorFieldEngine::drawTraces ( std::unique_ptr< QgsVectorFieldValueSource > source )

Seeds particles over the whole rendered extent, moves them one time step and draws their traces, sampling the vector field from source, which the engine takes ownership of.

Definition at line 119 of file qgsvectorfieldengine.cpp.

◆ operator=()

QgsVectorFieldEngine & QgsVectorFieldEngine::operator= ( const QgsVectorFieldEngine & )