Class: QgsLabelLineSettings¶

Contains settings related to how the label engine places and formats labels for line features (or polygon features which are labeled in a “perimeter” style mode).

Added in version 3.16.

Enums

`AnchorClipping`	Clipping behavior for line anchor calculation.
`AnchorTextPoint`	Anchor point of label text.
`AnchorType`	Line anchor types
`DirectionSymbolPlacement`	Placement options for direction symbols.

Methods

`addDirectionSymbol`	Returns `True` if '<' or '>' (or custom strings set via leftDirectionSymbol and rightDirectionSymbol) will be automatically added to the label text, pointing in the direction of the line or polygon ring.
`anchorClipping`	Returns the line anchor clipping mode, which dictates how line strings are clipped before calculating the line anchor placement.
`anchorTextPoint`	Returns the line anchor text point, which dictates which part of the label text should be placed at the `lineAnchorPercent()`.
`anchorType`	Returns the line anchor type, which dictates how the `lineAnchorPercent()` setting is handled.
`directionSymbolPlacement`	Returns the placement for direction symbols.
`leftDirectionSymbol`	Returns the string to use for left direction arrows.
`lineAnchorPercent`	Returns the percent along the line at which labels should be placed.
`mergeLines`	Returns `True` if connected line features with identical label text should be merged prior to generating label positions.
`overrunDistance`	Returns the distance which labels are allowed to overrun past the start or end of line features.
`overrunDistanceMapUnitScale`	Returns the map unit scale for label overrun distance.
`overrunDistanceUnit`	Returns the units for label overrun distance.
`placementFlags`	Returns the line placement flags, which dictate how line labels can be placed above or below the lines.
`reverseDirectionSymbol`	Returns `True` if direction symbols should be reversed.
`rightDirectionSymbol`	Returns the string to use for right direction arrows.
`setAddDirectionSymbol`	Sets whether '<' or '>' (or custom strings set via leftDirectionSymbol and rightDirectionSymbol) will be automatically added to the label text, pointing in the direction of the line or polygon ring.
`setAnchorClipping`	Sets the line anchor clipping mode, which dictates how line strings are clipped before calculating the line anchor placement.
`setAnchorTextPoint`	Sets the line anchor text point, which dictates which part of the label text should be placed at the `lineAnchorPercent()`.
`setAnchorType`	Sets the line anchor type, which dictates how the `lineAnchorPercent()` setting is handled.
`setDirectionSymbolPlacement`	Sets the placement for direction symbols.
`setLeftDirectionSymbol`	Sets the string to use for left direction arrows.
`setLineAnchorPercent`	Sets the percent along the line at which labels should be placed.
`setMergeLines`	Sets whether connected line features with identical label text should be merged prior to generating label positions.
`setOverrunDistance`	Sets the distance which labels are allowed to overrun past the start or end of line features.
`setOverrunDistanceMapUnitScale`	Sets the map unit scale for label overrun distance.
`setOverrunDistanceUnit`	Sets the unit for label overrun distance.
`setPlacementFlags`	Returns the line placement flags, which dictate how line labels can be placed above or below the lines.
`setReverseDirectionSymbol`	Sets whether the direction symbols should be reversed.
`setRightDirectionSymbol`	Sets the string to use for right direction arrows.
`updateDataDefinedProperties`	Updates the line settings to respect any data defined properties set within the specified properties collection.

class qgis.core.QgsLabelLineSettings[source]¶

Bases: object

class AnchorClipping(*values)¶

Bases: IntEnum

Clipping behavior for line anchor calculation.

Added in version 3.20.

UseVisiblePartsOfLine: Only visible parts of lines are considered when calculating the line anchor for labels
UseEntireLine: Entire original feature line geometry is used when calculating the line anchor for labels

UseEntireLine = 1¶

UseVisiblePartsOfLine = 0¶

class AnchorTextPoint(*values)¶

Bases: IntEnum

Anchor point of label text.

Added in version 3.26.

StartOfText: Anchor using start of text
CenterOfText: Anchor using center of text
EndOfText: Anchor using end of text
FollowPlacement: Automatically set the anchor point based on the lineAnchorPercent() value. Values <25% will use the start of text, values > 75% will use the end of text, and values in between will use the center of the text

CenterOfText = 1¶

EndOfText = 2¶

FollowPlacement = 3¶

StartOfText = 0¶

class AnchorType(*values)¶

Bases: IntEnum

Line anchor types

HintOnly: Line anchor is a hint for preferred placement only, but other placements close to the hint are permitted
Strict: Line anchor is a strict placement, and other placements are not permitted

HintOnly = 0¶

Strict = 1¶

class DirectionSymbolPlacement(*values)¶

Bases: IntEnum

Placement options for direction symbols.

SymbolLeftRight: Place direction symbols on left/right of label
SymbolAbove: Place direction symbols on above label
SymbolBelow: Place direction symbols on below label

SymbolAbove = 1¶

SymbolBelow = 2¶

SymbolLeftRight = 0¶

addDirectionSymbol(self) → bool[source]¶

Returns True if ‘<’ or ‘>’ (or custom strings set via leftDirectionSymbol and rightDirectionSymbol) will be automatically added to the label text, pointing in the direction of the line or polygon ring.

See also

setAddDirectionSymbol()

See also

leftDirectionSymbol()

See also

rightDirectionSymbol()

See also

directionSymbolPlacement()

See also

reverseDirectionSymbol()

Return type:: bool

anchorClipping(self) → QgsLabelLineSettings.AnchorClipping[source]¶

Returns the line anchor clipping mode, which dictates how line strings are clipped before calculating the line anchor placement.

See also

setAnchorClipping()

See also

anchorType()

See also

lineAnchorPercent()

Added in version 3.20.

Return type:: QgsLabelLineSettings.AnchorClipping

anchorTextPoint(self) → QgsLabelLineSettings.AnchorTextPoint[source]¶

Returns the line anchor text point, which dictates which part of the label text should be placed at the lineAnchorPercent().

See also

setAnchorTextPoint()

Added in version 3.26.

Return type:: QgsLabelLineSettings.AnchorTextPoint

anchorType(self) → QgsLabelLineSettings.AnchorType[source]¶

Returns the line anchor type, which dictates how the lineAnchorPercent() setting is handled.

See also

setAnchorType()

See also

lineAnchorPercent()

See also

anchorClipping()

Return type:: QgsLabelLineSettings.AnchorType

directionSymbolPlacement(self) → QgsLabelLineSettings.DirectionSymbolPlacement[source]¶

Returns the placement for direction symbols.

This setting controls whether to place direction symbols to the left/right, above or below label.

See also

setDirectionSymbolPlacement()

See also

addDirectionSymbol()

Return type:: QgsLabelLineSettings.DirectionSymbolPlacement

leftDirectionSymbol(self) → str[source]¶

Returns the string to use for left direction arrows.

See also

setLeftDirectionSymbol()

See also

addDirectionSymbol()

See also

rightDirectionSymbol()

Return type:: str

lineAnchorPercent(self) → float[source]¶

Returns the percent along the line at which labels should be placed.

By default, this is 0.5 which indicates that labels should be placed as close to the center of the line as possible. A value of 0.0 indicates that the labels should be placed as close to the start of the line as possible, while a value of 1.0 pushes labels towards the end of the line.

See also

setLineAnchorPercent()

See also

anchorTextPoint()

See also

anchorType()

See also

anchorClipping()

Return type:: float

mergeLines(self) → bool[source]¶

Returns True if connected line features with identical label text should be merged prior to generating label positions.

See also

setMergeLines()

Return type:: bool

overrunDistance(self) → float[source]¶

Returns the distance which labels are allowed to overrun past the start or end of line features.

See also

setOverrunDistance()

See also

overrunDistanceUnit()

See also

overrunDistanceMapUnitScale()

Return type:: float

overrunDistanceMapUnitScale(self) → QgsMapUnitScale[source]¶

Returns the map unit scale for label overrun distance.

See also

setOverrunDistanceMapUnitScale()

See also

overrunDistance()

See also

overrunDistanceUnit()

Return type:: QgsMapUnitScale

overrunDistanceUnit(self) → Qgis.RenderUnit[source]¶

Returns the units for label overrun distance.

See also

setOverrunDistanceUnit()

See also

overrunDistance()

See also

overrunDistanceMapUnitScale()

Return type:: Qgis.RenderUnit

placementFlags(self) → Qgis.LabelLinePlacementFlags[source]¶

Returns the line placement flags, which dictate how line labels can be placed above or below the lines.

See also

setPlacementFlags()

Return type:: Qgis.LabelLinePlacementFlags

reverseDirectionSymbol(self) → bool[source]¶

Returns True if direction symbols should be reversed.

See also

setReverseDirectionSymbol()

Return type:: bool

rightDirectionSymbol(self) → str[source]¶

Returns the string to use for right direction arrows.

See also

setRightDirectionSymbol()

See also

addDirectionSymbol()

See also

leftDirectionSymbol()

Return type:: str

setAddDirectionSymbol(self, enabled: bool)[source]¶

Sets whether ‘<’ or ‘>’ (or custom strings set via leftDirectionSymbol and rightDirectionSymbol) will be automatically added to the label text, pointing in the direction of the line or polygon ring.

See also

addDirectionSymbol()

See also

setLeftDirectionSymbol()

See also

setRightDirectionSymbol()

See also

setDirectionSymbolPlacement()

See also

setReverseDirectionSymbol()

Parameters:: enabled (bool)

setAnchorClipping(self, clipping: QgsLabelLineSettings.AnchorClipping)[source]¶

Sets the line anchor clipping mode, which dictates how line strings are clipped before calculating the line anchor placement.

See also

anchorClipping()

See also

setAnchorType()

See also

setLineAnchorPercent()

Added in version 3.20.

Parameters:: clipping (QgsLabelLineSettings.AnchorClipping)

setAnchorTextPoint(self, point: QgsLabelLineSettings.AnchorTextPoint)[source]¶

Sets the line anchor text point, which dictates which part of the label text should be placed at the lineAnchorPercent().

See also

anchorTextPoint()

Added in version 3.26.

Parameters:: point (QgsLabelLineSettings.AnchorTextPoint)

setAnchorType(self, type: QgsLabelLineSettings.AnchorType)[source]¶

Sets the line anchor type, which dictates how the lineAnchorPercent() setting is handled.

See also

anchorType()

See also

setLineAnchorPercent()

See also

setAnchorClipping()

Parameters:: type (QgsLabelLineSettings.AnchorType)

setDirectionSymbolPlacement(self, placement: QgsLabelLineSettings.DirectionSymbolPlacement)[source]¶

Sets the placement for direction symbols.

This setting controls whether to place direction symbols to the left/right, above or below label.

See also

directionSymbolPlacement()

See also

addDirectionSymbol()

Parameters:: placement (QgsLabelLineSettings.DirectionSymbolPlacement)

setLeftDirectionSymbol(self, symbol: str | None)[source]¶

Sets the string to use for left direction arrows.

See also

leftDirectionSymbol()

See also

addDirectionSymbol()

See also

rightDirectionSymbol()

Parameters:: symbol (Optional[str])

setLineAnchorPercent(self, percent: float)[source]¶

Sets the percent along the line at which labels should be placed.

By default, this is 0.5 which indicates that labels should be placed as close to the center of the line as possible. A value of 0.0 indicates that the labels should be placed as close to the start of the line as possible, while a value of 1.0 pushes labels towards the end of the line.

See also

lineAnchorPercent()

See also

setAnchorTextPoint()

See also

setAnchorType()

See also

setAnchorClipping()