Class: QgsSymbolRenderContext

class qgis.core.QgsSymbolRenderContext(c: QgsRenderContext, u: QgsUnitTypes.RenderUnit, opacity: float = 1, selected: bool = False, renderHints: Union[QgsSymbol.RenderHints, QgsSymbol.RenderHint] = QgsSymbol.RenderHints(), f: QgsFeature = None, fields: QgsFields = QgsFields(), mapUnitScale: QgsMapUnitScale = QgsMapUnitScale())

Bases: sip.wrapper

Constructor for QgsSymbolRenderContext

Parameters
expressionContextScope(self)QgsExpressionContextScope

This scope is always available when a symbol of this type is being rendered.

Return type

QgsExpressionContextScope

Returns

An expression scope for details about this symbol

feature(self)QgsFeature

Returns the current feature being rendered. This may be None.

Return type

QgsFeature

fields(self)QgsFields

Fields of the layer. Currently only available in startRender() calls to allow symbols with data-defined properties prepare the expressions (other times fields() returns an empty QgsFields object).

New in version 2.4.

Return type

QgsFields

geometryPartCount(self) → int

Part count of current geometry

New in version 2.16.

Return type

int

geometryPartNum(self) → int

Part number of current geometry

New in version 2.16.

Return type

int

mapUnitScale(self)QgsMapUnitScale

Deprecated since version Will: be removed in QGIS 4.0

Return type

QgsMapUnitScale

opacity(self) → float

Returns the opacity for the symbol.

Return type

float

Returns

opacity value between 0 (fully transparent) and 1 (fully opaque)

See also

setOpacity()

originalGeometryType(self)QgsWkbTypes.GeometryType

Returns the geometry type for the original feature geometry being rendered. This can be useful if symbol layers alter their appearance based on geometry type - eg offsetting a simple line style will look different if the simple line is rendering a polygon feature (a closed buffer) vs a line feature (an unclosed offset line).

New in version 3.0.

Return type

QgsWkbTypes.GeometryType

outputLineWidth(self, width: float) → float

Deprecated since version Use: the size conversion methods in QgsRenderContext instead.

Parameters

width (float) –

Return type

float

outputPixelSize(self, size: float) → float

Deprecated since version Use: the size conversion methods in QgsRenderContext instead.

Parameters

size (float) –

Return type

float

outputUnit(self)QgsUnitTypes.RenderUnit

Returns the output unit for the context.

Deprecated since version No: longer used and will be removed in QGIS 4.0

Return type

QgsUnitTypes.RenderUnit

patchShape(self)QgsLegendPatchShape

Returns the symbol patch shape, to use if rendering symbol preview icons.

See also

setPatchShape()

New in version 3.14.

Return type

QgsLegendPatchShape

renderContext(self)QgsRenderContext

Returns a reference to the context’s render context.

Return type

QgsRenderContext

renderHints(self)QgsSymbol.RenderHints

Returns the rendering hint flags for the symbol.

See also

setRenderHints()

Return type

QgsSymbol.RenderHints

selected(self) → bool

Returns True if symbols should be rendered using the selected symbol coloring and style.

See also

setSelected()

Return type

bool

setExpressionContextScope(self, contextScope: QgsExpressionContextScope)

Set an expression scope for this symbol.

Will take ownership.

Parameters

contextScope (QgsExpressionContextScope) – An expression scope for details about this symbol

setFeature(self, f: QgsFeature)
Parameters

f (QgsFeature) –

setGeometryPartCount(self, count: int)

Sets the part count of current geometry

New in version 2.16.

Parameters

count (int) –

setGeometryPartNum(self, num: int)

Sets the part number of current geometry

New in version 2.16.

Parameters

num (int) –

setMapUnitScale(self, scale: QgsMapUnitScale)

Deprecated since version Will: be removed in QGIS 4.0

Parameters

scale (QgsMapUnitScale) –

setOpacity(self, opacity: float)

Sets the opacity for the symbol.

Parameters

opacity (float) – opacity value between 0 (fully transparent) and 1 (fully opaque)

See also

opacity()

setOriginalGeometryType(self, type: QgsWkbTypes.GeometryType)

Sets the geometry type for the original feature geometry being rendered.

New in version 3.0.

Parameters

type (QgsWkbTypes.GeometryType) –

setOriginalValueVariable(self, value: Any)

Sets the original value variable value for data defined symbology

Parameters

value (Any) – value for original value variable. This usually represents the symbol property value before any data defined overrides have been applied.

New in version 2.12.

setOutputUnit(self, u: QgsUnitTypes.RenderUnit)

Sets the output unit for the context.

Deprecated since version No: longer used and will be removed in QGIS 4.0

Parameters

u (QgsUnitTypes.RenderUnit) –

setPatchShape(self, shape: QgsLegendPatchShape)

Sets the symbol patch shape, to use if rendering symbol preview icons.

See also

patchShape()

New in version 3.14.

Parameters

shape (QgsLegendPatchShape) –

setRenderHints(self, hints: Union[QgsSymbol.RenderHints, QgsSymbol.RenderHint])

Sets rendering hint flags for the symbol.

See also

renderHints()

Parameters

hints (Union[QgsSymbol.RenderHints) –

setSelected(self, selected: bool)

Sets whether symbols should be rendered using the selected symbol coloring and style.

See also

selected()

Parameters

selected (bool) –