Class: QgsTemplatedLineSymbolLayerBase

Base class for templated line symbols, e.g. line symbols which draw markers or hash lines at intervals along the line feature.

Added in version 3.8.

Note

This is an abstract class, with methods which must be implemented by a subclass.

The following methods must be implemented: QgsSymbolLayer.clone(), QgsSymbolLayer.layerType(), renderSymbol(), setSymbolAngle(), setSymbolLineAngle(), QgsSymbolLayer.startRender(), QgsSymbolLayer.stopRender(), symbolAngle()

Class Hierarchy

Base classes

QgsLineSymbolLayer	Abstract base class for line symbol layers.
QgsSymbolLayer	Abstract base class for symbol layers.

Subclasses

QgsHashedLineSymbolLayer	Line symbol layer type which draws repeating line sections along a line feature.
QgsMarkerLineSymbolLayer	Line symbol layer type which draws repeating marker symbols along a line feature.

Enums

Placement

alias of MarkerLinePlacement

Abstract Methods

renderSymbol	Renders the templated symbol at the specified point, using the given render context.
setSymbolAngle	Sets the symbol's angle, in degrees clockwise.
setSymbolLineAngle	Sets the line angle modification for the symbol's angle.
symbolAngle	Returns the symbol's current angle, in degrees clockwise.

Methods

averageAngleLength	Returns the length of line over which the line's direction is averaged when calculating individual symbol angles.
averageAngleMapUnitScale	Returns the map unit scale for the length over which the line's direction is averaged when calculating individual symbol angles.
averageAngleUnit	Returns the unit for the length over which the line's direction is averaged when calculating individual symbol angles.
copyTemplateSymbolProperties	Copies all common properties of this layer to another templated symbol layer.
interval	Returns the interval between individual symbols.
intervalMapUnitScale	Returns the map unit scale for the interval between symbols.
intervalUnit	Returns the units for the interval between symbols.
offsetAlongLine	Returns the offset along the line for the symbol placement.
offsetAlongLineMapUnitScale	Returns the map unit scale used for calculating the offset in map units along line for symbols.
offsetAlongLineUnit	Returns the unit used for calculating the offset along line for symbols.
placeOnEveryPart	Returns True if the placement applies for every part of multi-part feature geometries.
placement	Returns the placement of the symbols.
placements	Returns the placement of the symbols.
rotateSymbols	Returns True if the repeating symbols be rotated to match their line segment orientation.
setAverageAngleLength	Sets the length of line over which the line's direction is averaged when calculating individual symbol angles.
setAverageAngleMapUnitScale	Sets the map unit scale for the length over which the line's direction is averaged when calculating individual symbol angles.
setAverageAngleUnit	Sets the unit for the length over which the line's direction is averaged when calculating individual symbol angles.
setInterval	Sets the interval between individual symbols.
setIntervalMapUnitScale	Sets the map unit scale for the interval between symbols.
setIntervalUnit	Sets the units for the interval between symbols.
setOffsetAlongLine	Sets the the offset along the line for the symbol placement.
setOffsetAlongLineMapUnitScale	Sets the map unit scale used for calculating the offset in map units along line for symbols.
setOffsetAlongLineUnit	Sets the unit used for calculating the offset along line for symbols.
setPlaceOnEveryPart	Sets whether the placement applies for every part of multi-part feature geometries.
setPlacement	Sets the placement of the symbols.
setPlacements	Sets the placement of the symbols.
setRotateSymbols	Sets whether the repeating symbols should be rotated to match their line segment orientation.

Static Methods

setCommonProperties

Sets all common symbol properties in the destLayer, using the settings serialized in the properties map.

class qgis.core.QgsTemplatedLineSymbolLayerBase

Bases: QgsLineSymbolLayer

__init__(rotateSymbol: bool = True, interval: float = 3)

Constructor for QgsTemplatedLineSymbolLayerBase. Creates a template line placed at the specified interval (in millimeters).

The rotateSymbol argument specifies whether individual symbols should be rotated to match the line segment alignment.

Parameters:

• rotateSymbol (bool = True)

• interval (float = 3)

Placement

alias of MarkerLinePlacement

averageAngleLength(self) → float

Returns the length of line over which the line’s direction is averaged when calculating individual symbol angles. Longer lengths smooth out angles from jagged lines to a greater extent.

Units are retrieved through averageAngleUnit()

See also

setAverageAngleLength()

See also

averageAngleUnit()

See also

averageAngleMapUnitScale()

Return type:

float

averageAngleMapUnitScale(self) → QgsMapUnitScale

Returns the map unit scale for the length over which the line’s direction is averaged when calculating individual symbol angles.

See also

setAverageAngleMapUnitScale()

See also

averageAngleLength()

See also

averageAngleUnit()

Return type:

QgsMapUnitScale

averageAngleUnit(self) → Qgis.RenderUnit

Returns the unit for the length over which the line’s direction is averaged when calculating individual symbol angles.

See also

setAverageAngleUnit()

See also

averageAngleLength()

See also

averageAngleMapUnitScale()

Return type:

Qgis.RenderUnit

copyTemplateSymbolProperties(self, destLayer: QgsTemplatedLineSymbolLayerBase | None)

Copies all common properties of this layer to another templated symbol layer.

Parameters:

destLayer (Optional[QgsTemplatedLineSymbolLayerBase])

interval(self) → float

Returns the interval between individual symbols. Units are specified through intervalUnits().

See also

setInterval()

See also

intervalUnit()

Return type:

float

intervalMapUnitScale(self) → QgsMapUnitScale

Returns the map unit scale for the interval between symbols.

See also

setIntervalMapUnitScale()

See also

intervalUnit()

See also

interval()

Return type:

QgsMapUnitScale

intervalUnit(self) → Qgis.RenderUnit

Returns the units for the interval between symbols.

See also

setIntervalUnit()

See also

interval()

Return type:

Qgis.RenderUnit

offsetAlongLine(self) → float

Returns the offset along the line for the symbol placement. For Interval placements, this is the distance between the start of the line and the first symbol. For FirstVertex and LastVertex placements, this is the distance between the symbol and the start of the line or the end of the line respectively. This setting has no effect for Vertex or CentralPoint placements.

Return type:

float

Returns:

The offset along the line. The unit for the offset is retrievable via offsetAlongLineUnit.

See also

setOffsetAlongLine()

See also

offsetAlongLineUnit()

See also

placement()

offsetAlongLineMapUnitScale(self) → QgsMapUnitScale

Returns the map unit scale used for calculating the offset in map units along line for symbols.

See also

setOffsetAlongLineMapUnitScale()

Return type:

QgsMapUnitScale

offsetAlongLineUnit(self) → Qgis.RenderUnit

Returns the unit used for calculating the offset along line for symbols.

Return type:

Qgis.RenderUnit

Returns:

Offset along line unit type.

See also

setOffsetAlongLineUnit()

See also

offsetAlongLine()

placeOnEveryPart(self) → bool

Returns True if the placement applies for every part of multi-part feature geometries.

The default is True, which means that Qgis.MarkerLinePlacement.FirstVertex or Qgis.MarkerLinePlacement.LastVertex placements will result in a symbol on the first/last vertex of EVERY part of a multipart feature.

If False, then Qgis.MarkerLinePlacement.FirstVertex or Qgis.MarkerLinePlacement.LastVertex placements will result in a symbol on the first/last vertex of the overall multipart geometry only.

See also

setPlaceOnEveryPart()

Added in version 3.24.

Return type:

bool

placement(self) → Qgis.MarkerLinePlacement

Returns the placement of the symbols.

See also

setPlacement()

Deprecated since version 3.40: Use placements() instead.

Return type:

Qgis.MarkerLinePlacement

placements(self) → Qgis.MarkerLinePlacements

Returns the placement of the symbols.

See also

setPlacements()

Added in version 3.24.

Return type:

Qgis.MarkerLinePlacements

abstract renderSymbol(self, point: QPointF | QPoint, feature: QgsFeature | None, context: QgsRenderContext, layer: int = -1, selected: bool = False)

Renders the templated symbol at the specified point, using the given render context.

The feature argument is used to pass the feature currently being rendered (when available).

If only a single symbol layer from the symbol should be rendered, it should be specified in the layer argument. A layer of -1 indicates that all symbol layers should be rendered.

If selected is True then the symbol will be drawn using the “selected feature” style and colors instead of the symbol’s normal style.

Parameters:

• point (Union[QPointF, QPoint])

• feature (Optional[QgsFeature])

• context (QgsRenderContext)

• layer (int = -1)

• selected (bool = False)

rotateSymbols(self) → bool

Returns True if the repeating symbols be rotated to match their line segment orientation.

See also

setRotateSymbols()

Return type:

bool

setAverageAngleLength(self, length: float)

Sets the length of line over which the line’s direction is averaged when calculating individual symbol angles. Longer lengths smooth out angles from jagged lines to a greater extent.

Units are set through setAverageAngleUnit()

See also

averageAngleLength()

See also

setAverageAngleUnit()

See also

setAverageAngleMapUnitScale()

Parameters:

length (float)

setAverageAngleMapUnitScale(self, scale: QgsMapUnitScale)

Sets the map unit scale for the length over which the line’s direction is averaged when calculating individual symbol angles.

See also

averageAngleMapUnitScale()

See also

setAverageAngleLength()

See also

setAverageAngleUnit()

Parameters:

scale (QgsMapUnitScale)

setAverageAngleUnit(self, unit: Qgis.RenderUnit)

Sets the unit for the length over which the line’s direction is averaged when calculating individual symbol angles.

See also

averageAngleUnit()

See also

setAverageAngleLength()

See also

setAverageAngleMapUnitScale()

Parameters:

unit (Qgis.RenderUnit)

static setCommonProperties(destLayer: QgsTemplatedLineSymbolLayerBase | None, properties: Dict[str, Any])

Sets all common symbol properties in the destLayer, using the settings serialized in the properties map.

Parameters:

• destLayer (Optional[QgsTemplatedLineSymbolLayerBase])

• properties (Dict[str, Any])

setInterval(self, interval: float)

Sets the interval between individual symbols.

Parameters:

interval (float) – interval size. Units are specified through setIntervalUnit()

See also

interval()

See also

setIntervalUnit()

setIntervalMapUnitScale(self, scale: QgsMapUnitScale)

Sets the map unit scale for the interval between symbols.

See also

intervalMapUnitScale()

See also

setIntervalUnit()

See also

setInterval()

Parameters:

scale (QgsMapUnitScale)

setIntervalUnit(self, unit: Qgis.RenderUnit)

Sets the units for the interval between symbols.

Parameters:

unit (Qgis.RenderUnit) – interval units

See also

intervalUnit()

See also

setInterval()

setOffsetAlongLine(self, offsetAlongLine: float)

Sets the the offset along the line for the symbol placement. For Interval placements, this is the distance between the start of the line and the first symbol. For FirstVertex and LastVertex placements, this is the distance between the symbol and the start of the line or the end of the line respectively. This setting has no effect for Vertex or CentralPoint placements.

Parameters:

offsetAlongLine (float) – Distance to offset markers along the line. The offset unit is set via setOffsetAlongLineUnit.

See also

offsetAlongLine()

See also

setOffsetAlongLineUnit()

See also

setPlacement()

setOffsetAlongLineMapUnitScale(self, scale: QgsMapUnitScale)

Sets the map unit scale used for calculating the offset in map units along line for symbols.

See also

offsetAlongLineMapUnitScale()

Parameters:

scale (QgsMapUnitScale)

setOffsetAlongLineUnit(self, unit: Qgis.RenderUnit)

Sets the unit used for calculating the offset along line for symbols.

Parameters:

unit (Qgis.RenderUnit) – Offset along line unit type.

See also

offsetAlongLineUnit()

See also

setOffsetAlongLine()

setPlaceOnEveryPart(self, respect: bool)

Sets whether the placement applies for every part of multi-part feature geometries.

The default is True, which means that Qgis.MarkerLinePlacement.FirstVertex or Qgis.MarkerLinePlacement.LastVertex placements will result in a symbol on the first/last vertex of EVERY part of a multipart feature.

If False, then Qgis.MarkerLinePlacement.FirstVertex or Qgis.MarkerLinePlacement.LastVertex placements will result in a symbol on the first/last vertex of the overall multipart geometry only.

See also

placeOnEveryPart()

Added in version 3.24.

Parameters:

respect (bool)

setPlacement(self, placement: Qgis.MarkerLinePlacement)

Sets the placement of the symbols.

See also

placement()

Deprecated since version 3.40: Use setPlacements() instead.

Parameters:

placement (Qgis.MarkerLinePlacement)

setPlacements(self, placements: Qgis.MarkerLinePlacements | Qgis.MarkerLinePlacement)

Sets the placement of the symbols.

See also

placements()

Added in version 3.24.

Parameters:

placements (Union[Qgis.MarkerLinePlacements, Qgis.MarkerLinePlacement])

setRotateSymbols(self, rotate: bool)

Sets whether the repeating symbols should be rotated to match their line segment orientation.

See also

rotateSymbols()

Parameters:

rotate (bool)

abstract setSymbolAngle(self, angle: float)

Sets the symbol’s angle, in degrees clockwise.

Parameters:

angle (float)

abstract setSymbolLineAngle(self, angle: float)

Sets the line angle modification for the symbol’s angle. This angle is added to the symbol’s rotation and data defined rotation before rendering the symbol, and is used for orienting symbols to match the line’s angle.

Parameters:

angle (float) – Angle in degrees, valid values are between 0 and 360

abstract symbolAngle(self) → float

Returns the symbol’s current angle, in degrees clockwise.

Return type:

float