Class: QgsEffectStack¶
-
class
qgis.core.
QgsEffectStack
¶ Bases:
QgsPaintEffect
Constructor for empty QgsEffectStack.
QgsEffectStack(other:
QgsEffectStack
)QgsEffectStack(effect:
QgsPaintEffect
) Creates a newQgsEffectStack
effect from a single initial effect.- Parameters
effect – initial effect to add to the stack. The effect will be cloned, so ownership is not transferred to the stack.
- Returns
new
QgsEffectStack
containing initial effect
A paint effect which consists of a stack of other chained paint effects
Effect stacks can be used to apply multiple paint effects to a QPicture. For instance, an effect stack may blur then apply a drop shadow.
The way in which effects apply to a stack is controlled by the effect’s drawMode. Effects can either render their results onto the destination paint device, or just modify the source picture which is drawn by subsequent effects in the stack. For instance, a blur effect with a Modifier drawMode will blur the source picture for the following drop shadow effect without actually drawing the blurred picture to the paint device. If the blur effect had a Render drawMode then the blurred picture will be drawn on the paint device, but the following drop shadow effect will be drawn using the original picture, not the blurred version.
Methods
Appends an effect to the end of the stack.
Replaces the effect at a specified position within the stack.
- rtype
QgsEffectStack
Returns count of effects contained by the stack
Creates a new
QgsEffectStack
effect.- param context
Returns a pointer to the effect at a specified index within the stack
Returns a pointer to the list of effects currently contained by the stack
Inserts an effect at a specified index within the stack.
Unused for
QgsEffectStack
, will always return an empty string mapreadProperties(self, props: Dict[str, str]) Unused for
QgsEffectStack
, props parameter will be ignored- param doc
Removes an effect from the stack and returns a pointer to it.
- rtype
str
-
appendEffect
(self, effect: QgsPaintEffect)¶ Appends an effect to the end of the stack.
- Parameters
effect (QgsPaintEffect) –
QgsPaintEffect
to append. Ownership of the effect will be transferred to the stack object.
See also
-
boundingRect
()¶
-
changeEffect
(self, index: int, effect: QgsPaintEffect) → bool¶ Replaces the effect at a specified position within the stack.
- Parameters
index (int) – position of effect to replace
effect (QgsPaintEffect) –
QgsPaintEffect
to replace with. Ownership of the effect will be transferred to the stack object.
- Return type
bool
-
clone
(self) → QgsEffectStack¶ - Return type
-
count
(self) → int¶ Returns count of effects contained by the stack
- Return type
int
- Returns
count of effects
-
create
(map: Dict[str, str]) → QgsPaintEffect¶ Creates a new
QgsEffectStack
effect. This method ignores the map parameter, and always returns an empty effect stack.- Parameters
map (Dict[str) – unused encoded properties string map
- Return type
- Returns
new QgsEffectStack
-
draw
(self, context: QgsRenderContext)¶ - Parameters
context (QgsRenderContext) –
-
drawSource
()¶
-
effect
(self, index: int) → QgsPaintEffect¶ Returns a pointer to the effect at a specified index within the stack
- Parameters
index (int) – position of effect to return
- Return type
- Returns
QgsPaintEffect
at specified position
-
effectList
(self) → object¶ Returns a pointer to the list of effects currently contained by the stack
- Return type
object
- Returns
list of
QgsPaintEffects
within the stack
-
fixQPictureDpi
()¶
-
imageOffset
()¶
-
insertEffect
(self, index: int, effect: QgsPaintEffect) → bool¶ Inserts an effect at a specified index within the stack.
- Parameters
index (int) – position to insert the effect
effect (QgsPaintEffect) –
QgsPaintEffect
to insert. Ownership of the effect will be transferred to the stack object.
See also
- Return type
bool
-
properties
(self) → Dict[str, str]¶ Unused for
QgsEffectStack
, will always return an empty string map- Return type
Dict[str, str]
-
readProperties
(self, element: QDomElement) → bool¶ readProperties(self, props: Dict[str, str]) Unused for
QgsEffectStack
, props parameter will be ignored- Parameters
element (QDomElement) –
- Return type
bool
-
saveProperties
(self, doc: QDomDocument, element: QDomElement) → bool¶ - Parameters
doc (QDomDocument) –
element (QDomElement) –
- Return type
bool
-
source
()¶
-
sourceAsImage
()¶
-
takeEffect
(self, index: int) → QgsPaintEffect¶ Removes an effect from the stack and returns a pointer to it.
- Parameters
index (int) – position of effect to take
- Return type
-
type
(self) → str¶ - Return type
str