Trait animate::EffectExt [−][src]
pub trait EffectExt: 'static {
fn queue_repaint(&self);
}Required methods
fn queue_repaint(&self)[src]
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 EffectPaintFlags::ActorDirty 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 ActorExt::continue_paint if it can draw a cached
image. This is mostly intended for effects that are using a
dx::Offscreen to redirect the actor (such as
OffscreenEffect). 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 EffectExt::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 EffectPaintFlags::ActorDirty 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 EffectPaintFlags::ActorDirty 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 EffectPaintFlags::ActorDirty
flag set.