Class: QgsTransformEffect

class qgis.core.QgsTransformEffect

Bases: QgsPaintEffect

Constructor for QgsTransformEffect.

A paint effect which applies transformations (such as move, scale and rotate) to a picture.

Methods

boundingRect

param rect

clone

rtype

QgsTransformEffect

create

Creates a new QgsTransformEffect effect from a properties string map.

draw

param context

drawSource

Draws the source QPicture onto the specified painter.

fixQPictureDpi

Applies a workaround to a QPainter to avoid an issue with incorrect scaling when drawing QPictures.

imageOffset

Returns the offset which should be used when drawing the source image on to a destination render context.

properties

rtype

Dict[str, str]

readProperties

param props

reflectX

Returns whether transform will be reflected along the x-axis

reflectY

Returns whether transform will be reflected along the y-axis

rotation

Returns the transform rotation, in degrees clockwise.

scaleX

Returns the x axis scaling factor.

scaleY

Returns the y axis scaling factor.

setReflectX

Sets whether to reflect along the x-axis

setReflectY

Sets whether to reflect along the y-axis

setRotation

Sets the transform rotation, in degrees clockwise.

setScaleX

Sets the x axis scaling factor.

setScaleY

Sets the y axis scaling factor.

setShearX

Sets the x axis shearing factor.

setShearY

Sets the y axis shearing factor.

setTranslateMapUnitScale

Sets the map unit scale used for the transform translation.

setTranslateUnit

Sets the units used for the transform translation.

setTranslateX

Sets the transform x translation.

setTranslateY

Sets the transform y translation.

shearX

Returns the x axis shearing factor.

shearY

Returns the y axis shearing factor.

source

Returns the source QPicture.

sourceAsImage

Returns the source QPicture rendered to a new QImage.

translateMapUnitScale

Returns the map unit scale used for the transform translation.

translateUnit

Returns the units used for the transform translation.

translateX

Returns the transform x translation.

translateY

Returns the transform y translation.

type

rtype

str

boundingRect(self, rect: QRectF, context: QgsRenderContext) → QRectF
Parameters
Return type

QRectF

clone(self)QgsTransformEffect
Return type

QgsTransformEffect

create(map: Dict[str, str])QgsPaintEffect

Creates a new QgsTransformEffect effect from a properties string map.

Parameters

map (Dict[str) – encoded properties string map

Return type

QgsPaintEffect

Returns

new QgsTransformEffect

draw(self, context: QgsRenderContext)
Parameters

context (QgsRenderContext) –

drawSource(self, painter: QPainter)

Draws the source QPicture onto the specified painter. Handles scaling of the picture to account for the destination painter’s DPI.

Parameters

painter – destination painter

See also

source()

See also

sourceAsImage()

fixQPictureDpi(self, painter: QPainter)

Applies a workaround to a QPainter to avoid an issue with incorrect scaling when drawing QPictures. This may need to be called by derived classes prior to rendering results onto a painter.

Parameters

painter – destination painter

imageOffset(self, context: QgsRenderContext) → QPointF

Returns the offset which should be used when drawing the source image on to a destination render context.

Parameters

context – destination render context

Returns

point offset for image top left corner

See also

sourceAsImage()

properties(self) → Dict[str, str]
Return type

Dict[str, str]

readProperties(self, props: Dict[str, str])
Parameters

props (Dict[str) –

reflectX(self) → bool

Returns whether transform will be reflected along the x-axis

Return type

bool

Returns

True if transform will reflect horizontally

See also

setReflectX()

See also

reflectY()

reflectY(self) → bool

Returns whether transform will be reflected along the y-axis

Return type

bool

Returns

True if transform will reflect horizontally

See also

setReflectY()

See also

reflectX()

rotation(self) → float

Returns the transform rotation, in degrees clockwise.

See also

setRotation()

Return type

float

scaleX(self) → float

Returns the x axis scaling factor.

Return type

float

Returns

x axis scaling factor, where 1.0 = no scaling

See also

setScaleX()

See also

scaleY()

scaleY(self) → float

Returns the y axis scaling factor.

Return type

float

Returns

y axis scaling factor, where 1.0 = no scaling

See also

setScaleY()

See also

scaleX()

setReflectX(self, reflectX: bool)

Sets whether to reflect along the x-axis

Parameters

reflectX (bool) – True to reflect horizontally

See also

reflectX()

See also

setReflectY()

setReflectY(self, reflectY: bool)

Sets whether to reflect along the y-axis

Parameters

reflectY (bool) – True to reflect horizontally

See also

reflectY()

See also

setReflectX()

setRotation(self, rotation: float)

Sets the transform rotation, in degrees clockwise.

See also

rotation()

Parameters

rotation (float) –

setScaleX(self, scaleX: float)

Sets the x axis scaling factor.

Parameters

scaleX (float) – factor to scale x axis by, where 1.0 = no scaling

See also

scaleX()

See also

setScaleY()

setScaleY(self, scaleY: float)

Sets the y axis scaling factor.

Parameters

scaleY (float) – factor to scale y axis by, where 1.0 = no scaling

See also

scaleX()

setShearX(self, shearX: float)

Sets the x axis shearing factor.

Parameters

shearX (float) – x axis shearing

See also

shearX()

See also

setShearY()

setShearY(self, shearY: float)

Sets the y axis shearing factor.

Parameters

shearY (float) – y axis shearing

See also

shearY()

See also

setShearX()

setTranslateMapUnitScale(self, scale: QgsMapUnitScale)

Sets the map unit scale used for the transform translation.

Parameters

scale (QgsMapUnitScale) – map unit scale for translation

See also

setTranslateX()

See also

setTranslateY()

setTranslateUnit(self, unit: QgsUnitTypes.RenderUnit)

Sets the units used for the transform translation.

Parameters

unit (QgsUnitTypes.RenderUnit) – units for translation

See also

translateUnit()

See also

setTranslateX()

See also

setTranslateY()

setTranslateX(self, translateX: float)

Sets the transform x translation.

Parameters

translateX (float) – distance to translate along the x axis

See also

translateX()

See also

setTranslateY()

setTranslateY(self, translateY: float)

Sets the transform y translation.

Parameters

translateY (float) – distance to translate along the y axis

See also

translateY()

See also

setTranslateX()

shearX(self) → float

Returns the x axis shearing factor.

Return type

float

Returns

x axis shearing

See also

setShearX()

See also

shearY()

shearY(self) → float

Returns the y axis shearing factor.

Return type

float

Returns

y axis shearing

See also

setShearY()

See also

shearX()

source(self) → QPicture

Returns the source QPicture. The draw() member can utilize this when drawing the effect.

Returns

source QPicture

See also

drawSource()

See also

sourceAsImage()

sourceAsImage(self, context: QgsRenderContext) → QImage

Returns the source QPicture rendered to a new QImage. The draw() member can utilize this when drawing the effect. The image will be padded or cropped from the original source QPicture by the results of the boundingRect() method. The result is cached to speed up subsequent calls to sourceAsImage.

Returns

source QPicture rendered to an image

See also

drawSource()

See also

source()

See also

imageOffset()

See also

boundingRect()

translateMapUnitScale(self)QgsMapUnitScale

Returns the map unit scale used for the transform translation.

Return type

QgsMapUnitScale

Returns

map unit scale for translation

See also

translateX()

See also

translateY()

See also

translateUnit()

translateUnit(self)QgsUnitTypes.RenderUnit

Returns the units used for the transform translation.

Return type

QgsUnitTypes.RenderUnit

Returns

units for translation

See also

translateX()

See also

translateY()

translateX(self) → float

Returns the transform x translation.

Return type

float

Returns

X distance translated along the x axis

See also

setTranslateX()

See also

translateY()

See also

translateUnit()

translateY(self) → float

Returns the transform y translation.

Return type

float

Returns

Y distance translated along the y axis

See also

setTranslateY()

See also

translateX()

See also

translateUnit()

type(self) → str
Return type

str