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@deffn Function clutter-effect-queue-repaint  (self@tie{}@code{<clutter-effect>})
@deffnx Method queue-repaint
Queues a repaint of the effect. The effect can detect when the
‘paint’ method is called as a result of this function because it
will not have the @samp{CLUTTER_EFFECT_PAINT_ACTOR_DIRTY} flag set. In
that case the effect is free to assume that the actor has not changed
its appearance since the last time it was painted so it doesn't need to
call @code{clutter-actor-continue-paint} if it can draw a cached image.
This is mostly intended for effects that are using a
@samp{CoglOffscreen} to redirect the actor (such as
@samp{ClutterOffscreenEffect}). In that case the effect can save a bit
of rendering time by painting the cached texture without causing the
entire actor to be painted.

This function can be used by effects that have their own animatable
parameters. For example, an effect which adds a varying degree of a red
tint to an actor by redirecting it through a CoglOffscreen might have a
property to specify the level of tint. When this value changes, the
underlying actor doesn't need to be redrawn so the effect can call
@code{clutter-effect-queue-repaint} to make sure the effect is
repainted.

Note however that modifying the position of the parent of an actor may
change the appearance of the actor because its transformation matrix
would change. In this case a redraw wouldn't be queued on the actor
itself so the @samp{CLUTTER_EFFECT_PAINT_ACTOR_DIRTY} would still not be
set. The effect can detect this case by keeping track of the last
modelview matrix that was used to render the actor and veryifying that
it remains the same in the next paint.

Any other effects that are layered on top of the passed in effect will
still be passed the @samp{CLUTTER_EFFECT_PAINT_ACTOR_DIRTY} flag. If
anything queues a redraw on the actor without specifying an effect or
with an effect that is lower in the chain of effects than this one then
that will override this call. In that case this effect will instead be
called with the @samp{CLUTTER_EFFECT_PAINT_ACTOR_DIRTY} flag set.

@table @var
@item effect
A @code{<clutter-effect>} which needs redrawing

@end table

Since 1.8

@end deffn


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