QgsModelSnapper Class Reference

Manages snapping grids and preset snap lines in a layout, and handles snapping points to the nearest grid coordinate/snap line when possible. More...

#include <qgsmodelsnapper.h>

Public Member Functions
	QgsModelSnapper ()
	Constructor for QgsModelSnapper, attached to the specified layout.
void	setSnapToGrid (bool enabled)
	Sets whether snapping to grid is enabled.
void	setSnapTolerance (int snapTolerance)
	Sets the snap tolerance (in pixels) to use when snapping.
QPointF	snapPoint (QPointF point, double scaleFactor, bool &snapped, bool snapHorizontal=true, bool snapVertical=true) const
	Snaps a layout coordinate point.
QPointF	snapPointsToGrid (const QList< QPointF > &points, double scaleFactor, bool &snappedX, bool &snappedY) const
	Snaps a set of points to the grid.
QPointF	snapPointToGrid (QPointF point, double scaleFactor, bool &snappedX, bool &snappedY) const
	Snaps a layout coordinate point to the grid.
QRectF	snapRect (const QRectF &rect, double scaleFactor, bool &snapped, bool snapHorizontal=true, bool snapVertical=true) const
	Snaps a layout coordinate rect.
QRectF	snapRectWithResize (const QRectF &rect, double scaleFactor, bool &snapped, bool snapHorizontal=true, bool snapVertical=true) const
	Snaps a layout coordinate rect.
bool	snapToGrid () const
	Returns true if snapping to grid is enabled.
int	snapTolerance () const
	Returns the snap tolerance (in pixels) to use when snapping.

Detailed Description

Manages snapping grids and preset snap lines in a layout, and handles snapping points to the nearest grid coordinate/snap line when possible.

Since

QGIS 3.14

Definition at line 33 of file qgsmodelsnapper.h.

Constructor & Destructor Documentation

QgsModelSnapper()

QgsModelSnapper::QgsModelSnapper

(

)

Constructor for QgsModelSnapper, attached to the specified layout.

Definition at line 21 of file qgsmodelsnapper.cpp.

Member Function Documentation

setSnapToGrid()

void QgsModelSnapper::setSnapToGrid

(

bool

enabled

)

Sets whether snapping to grid is enabled.

See also

snapToGrid()

Definition at line 32 of file qgsmodelsnapper.cpp.

setSnapTolerance()

void QgsModelSnapper::setSnapTolerance

(

int

snapTolerance

)

Sets the snap tolerance (in pixels) to use when snapping.

See also

snapTolerance()

Definition at line 27 of file qgsmodelsnapper.cpp.

snapPoint()

QPointF QgsModelSnapper::snapPoint	(	QPointF	point,
		double	scaleFactor,
		bool &	snapped,
		bool	snapHorizontal = true,
		bool	snapVertical = true
	)		const

Snaps a layout coordinate point.

If point was snapped, snapped will be set to true.

The scaleFactor argument should be set to the transformation from scalar transform from layout coordinates to pixels, i.e. the graphics view transform().m11() value.

This method considers snapping to the grid, snap lines, etc.

If the horizontalSnapLine and verticalSnapLine arguments are specified, then the snapper will automatically display and position these lines to indicate snapping positions to item bounds.

A list of items to ignore during the snapping can be specified via the ignoreItems list.

See also

snapRect()

Definition at line 37 of file qgsmodelsnapper.cpp.

snapPointsToGrid()

QPointF QgsModelSnapper::snapPointsToGrid	(	const QList< QPointF > &	points,
		double	scaleFactor,
		bool &	snappedX,
		bool &	snappedY
	)		const

Snaps a set of points to the grid.

If the points were snapped, snapped will be set to true.

The scaleFactor argument should be set to the transformation from scalar transform from layout coordinates to pixels, i.e. the graphics view transform().m11() value.

If snapToGrid() is disabled, this method will not attempt to snap the points.

The returned value is the smallest delta which the points need to be shifted by in order to align one of the points to the grid.

See also

snapPointToGrid()

Definition at line 121 of file qgsmodelsnapper.cpp.

snapPointToGrid()

QPointF QgsModelSnapper::snapPointToGrid	(	QPointF	point,
		double	scaleFactor,
		bool &	snappedX,
		bool &	snappedY
	)		const

Snaps a layout coordinate point to the grid.

If point was snapped horizontally, snappedX will be set to true. If point was snapped vertically, snappedY will be set to true.

The scaleFactor argument should be set to the transformation from scalar transform from layout coordinates to pixels, i.e. the graphics view transform().m11() value.

If snapToGrid() is disabled, this method will return the point unchanged.

See also

snapPointsToGrid()

Definition at line 115 of file qgsmodelsnapper.cpp.

snapRect()

QRectF QgsModelSnapper::snapRect	(	const QRectF &	rect,
		double	scaleFactor,
		bool &	snapped,
		bool	snapHorizontal = true,
		bool	snapVertical = true
	)		const

Snaps a layout coordinate rect.

If rect was snapped, snapped will be set to true.

Snapping occurs by moving the rectangle alone. The rectangle will not be resized as a result of the snap operation.

The scaleFactor argument should be set to the transformation from scalar transform from layout coordinates to pixels, i.e. the graphics view transform().m11() value.

This method considers snapping to the grid, snap lines, etc.

If the horizontalSnapLine and verticalSnapLine arguments are specified, then the snapper will automatically display and position these lines to indicate snapping positions to item bounds.

A list of items to ignore during the snapping can be specified via the ignoreItems list.

See also

snapPoint()

Definition at line 58 of file qgsmodelsnapper.cpp.

snapRectWithResize()

QRectF QgsModelSnapper::snapRectWithResize	(	const QRectF &	rect,
		double	scaleFactor,
		bool &	snapped,
		bool	snapHorizontal = true,
		bool	snapVertical = true
	)		const

Snaps a layout coordinate rect.

If rect was snapped, snapped will be set to true.

The scaleFactor argument should be set to the transformation from scalar transform from layout coordinates to pixels, i.e. the graphics view transform().m11() value.

This method considers snapping to the grid, snap lines, etc.

If the horizontalSnapLine and verticalSnapLine arguments are specified, then the snapper will automatically display and position these lines to indicate snapping positions to item bounds.

A list of items to ignore during the snapping can be specified via the ignoreItems list.

See also

snapPoint()

Definition at line 82 of file qgsmodelsnapper.cpp.

snapToGrid()

bool QgsModelSnapper::snapToGrid ( ) const

inline

Returns true if snapping to grid is enabled.

See also

setSnapToGrid()

Definition at line 57 of file qgsmodelsnapper.h.

snapTolerance()

int QgsModelSnapper::snapTolerance ( ) const

inline

Returns the snap tolerance (in pixels) to use when snapping.

See also

setSnapTolerance()

Definition at line 51 of file qgsmodelsnapper.h.

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

• /build/qgis-3.41.0+git20241228+57ec4277f5e+99sid/src/gui/processing/models/qgsmodelsnapper.h
• /build/qgis-3.41.0+git20241228+57ec4277f5e+99sid/src/gui/processing/models/qgsmodelsnapper.cpp