Class: QgsDrawSourceEffect¶
-
class
qgis.core.
QgsDrawSourceEffect
¶ Bases:
QgsPaintEffect
Constructor for QgsDrawSourceEffect
QgsDrawSourceEffect(
QgsDrawSourceEffect
)A paint effect which draws the source picture with minor or no alterations
The draw source effect can be used to draw an unaltered copy of the original source picture. Minor changes like lowering the opacity and applying a blend mode are supported, however these changes will force the resultant output to be rasterized. If no alterations are performed then the original picture will be rendered as a vector.
Methods
Returns the blend mode for the effect
Returns the bounding rect required for drawing the effect.
- rtype
QgsDrawSourceEffect
Creates a new
QgsDrawSource
effect from a properties string map.- param context
Draws the source QPicture onto the specified painter.
Applies a workaround to a QPainter to avoid an issue with incorrect scaling when drawing QPictures.
Returns the offset which should be used when drawing the source image on to a destination render context.
Returns the opacity for the effect
- rtype
Dict[str, str]
- param props
Sets the blend mode for the effect
Sets the
opacity
for the effect.Returns the source QPicture.
Returns the source QPicture rendered to a new QImage.
- rtype
str
-
blendMode
(self) → QPainter.CompositionMode¶ Returns the blend mode for the effect
- Return type
QPainter.CompositionMode
- Returns
blend mode used for drawing the source on to a destination paint device
See also
-
boundingRect
(self, rect: QRectF, context: QgsRenderContext) → QRectF¶ Returns the bounding rect required for drawing the effect. This method can be used to expand the bounding rect of a source picture to account for offset or blurring effects.
- Parameters
rect – original source bounding rect
context – destination render context
- Returns
modified bounding rect
See also
-
clone
(self) → QgsDrawSourceEffect¶ - Return type
-
create
(map: Dict[str, str]) → QgsPaintEffect¶ Creates a new
QgsDrawSource
effect from a properties string map.- Parameters
map (Dict[str) – encoded properties string map
- Return type
- Returns
new QgsDrawSourceEffect
-
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
See also
-
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
-
opacity
(self) → float¶ Returns the opacity for the effect
- Return type
float
- Returns
opacity value between 0 and 1 inclusive, where 0 is fully transparent and 1 is fully opaque
See also
-
properties
(self) → Dict[str, str]¶ - Return type
Dict[str, str]
-
readProperties
(self, props: Dict[str, str])¶ - Parameters
props (Dict[str) –
-
setBlendMode
(self, mode: QPainter.CompositionMode)¶ Sets the blend mode for the effect
- Parameters
mode (QPainter.CompositionMode) – blend mode used for drawing the source on to a destination paint device
See also
-
setOpacity
(self, opacity: float)¶ Sets the
opacity
for the effect.- Parameters
opacity (float) – double between 0 and 1 inclusive, where 0 is fully transparent and 1 is fully opaque
See also
-
source
(self) → QPicture¶ Returns the source QPicture. The draw() member can utilize this when drawing the effect.
- Returns
source QPicture
See also
See also
-
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
See also
See also
See also
-
type
(self) → str¶ - Return type
str