Correctly pass screenshot fences to transaction callbacks
In some instances, a screenshot may be captured before a layer has a
release callback registered. This can happen when a new buffer has
not yet been transacted before a screenshot is captured. This causes the
screenshot fence to be dropped and the possibility of tearing when
capturing a screenshot while continuously rendering.
To resolve this, buffer screenshot fences into a list of future fences
when there is no callback registered, and merge those fences when
dispatching the release callback.
Bug: 302703346
Test: SurfaceViewTests#testMovingWhiteSurfaceView 100 times
Change-Id: I91aec3cdb0973092d48cd77e59dd3999e9d9e847
diff --git a/include/ftl/details/future.h b/include/ftl/details/future.h
index df1323e..8d82e0f 100644
--- a/include/ftl/details/future.h
+++ b/include/ftl/details/future.h
@@ -73,8 +73,18 @@
return std::get<Impl>(self()).get();
}
+ template <class Rep, class Period>
+ std::future_status wait_for(const std::chrono::duration<Rep, Period>& timeout_duration) const {
+ if (std::holds_alternative<T>(self())) {
+ return std::future_status::ready;
+ }
+
+ return std::get<Impl>(self()).wait_for(timeout_duration);
+ }
+
private:
auto& self() { return static_cast<Self&>(*this).future_; }
+ const auto& self() const { return static_cast<const Self&>(*this).future_; }
};
template <typename Self, typename T>
@@ -90,6 +100,15 @@
return std::get<Impl>(self()).get();
}
+ template <class Rep, class Period>
+ std::future_status wait_for(const std::chrono::duration<Rep, Period>& timeout_duration) const {
+ if (std::holds_alternative<T>(self())) {
+ return std::future_status::ready;
+ }
+
+ return std::get<Impl>(self()).wait_for(timeout_duration);
+ }
+
private:
const auto& self() const { return static_cast<const Self&>(*this).future_; }
};
diff --git a/include/ftl/future.h b/include/ftl/future.h
index c78f9b7..dad180f 100644
--- a/include/ftl/future.h
+++ b/include/ftl/future.h
@@ -51,6 +51,7 @@
// Forwarding functions. Base::share is only defined when FutureImpl is std::future, whereas the
// following are defined for either FutureImpl:
using Base::get;
+ using Base::wait_for;
// Attaches a continuation to the future. The continuation is a function that maps T to either R
// or ftl::Future<R>. In the former case, the chain wraps the result in a future as if by