Class: QgsSymbolRenderContext¶
-
class
qgis.core.
QgsSymbolRenderContext
(c: QgsRenderContext, u: QgsUnitTypes.RenderUnit, opacity: float = 1, selected: bool = False, renderHints: Union[QgsSymbol.RenderHints, QgsSymbol.RenderHint] = 0, f: QgsFeature = None, fields: QgsFields = QgsFields(), mapUnitScale: QgsMapUnitScale = QgsMapUnitScale())¶ Bases:
sip.wrapper
Constructor for QgsSymbolRenderContext
- Parameters
c (QgsRenderContext) –
u (QgsUnitTypes.RenderUnit) –
opacity (float = 1) – value between 0 (fully transparent) and 1 (fully opaque)
selected (bool = False) – set to true if symbol should be drawn in a “selected” state
renderHints (Union[QgsSymbol.RenderHints) – flags controlling rendering behavior
f (
QgsFeature
= None) –fields (
QgsFields
= QgsFields()) –mapUnitScale (
QgsMapUnitScale
= QgsMapUnitScale()) –Methods
This scope is always available when a symbol of this type is being rendered.
Current feature being rendered - may be null
Fields of the layer.
Part count of current geometry
Part number of current geometry
- rtype
QgsMapUnitScale
Returns the opacity for the symbol.
Returns the geometry type for the original feature geometry being rendered.
- param width
- param size
Returns the output unit for the context
Returns a reference to the context’s render context.
Returns the rendering hint flags for the symbol.
- rtype
bool
Set an expression scope for this symbol.
- param f
Sets the part count of current geometry
Sets the part number of current geometry
- param scale
Sets the
opacity
for the symbol.Sets the geometry type for the original feature geometry being rendered.
Sets the original value variable value for data defined symbology
Sets the output unit for the context
Sets rendering hint flags for the symbol.
- param selected
-
expressionContextScope
(self) → QgsExpressionContextScope¶ This scope is always available when a symbol of this type is being rendered.
- Return type
- Returns
An expression scope for details about this symbol
-
feature
(self) → QgsFeature¶ Current feature being rendered - may be null
- Return type
-
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 null)
New in version 2.4.
- Return type
-
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¶ - Return type
-
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
-
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).
See also
New in version 3.0.
- Return type
-
outputLineWidth
(self, width: float) → float¶ - Parameters
width (float) –
- Return type
float
-
outputPixelSize
(self, size: float) → float¶ - Parameters
size (float) –
- Return type
float
-
outputUnit
(self) → QgsUnitTypes.RenderUnit¶ Returns the output unit for the context
- Return type
-
renderContext
(self) → QgsRenderContext¶ Returns a reference to the context’s render context.
- Return type
-
renderHints
(self) → QgsSymbol.RenderHints¶ Returns the rendering hint flags for the symbol.
See also
- Return type
-
selected
(self) → bool¶ - 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)¶ - 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
-
setOriginalGeometryType
(self, type: QgsWkbTypes.GeometryType)¶ Sets the geometry type for the original feature geometry being rendered.
See also
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
- Parameters
u (QgsUnitTypes.RenderUnit) –
-
setRenderHints
(self, hints: Union[QgsSymbol.RenderHints, QgsSymbol.RenderHint])¶ Sets rendering hint flags for the symbol.
See also
- Parameters
hints (Union[QgsSymbol.RenderHints) –
-
setSelected
(self, selected: bool)¶ - Parameters
selected (bool) –