[scenic] Document ImagePipe2 fence reuse requirements
Document that the acquire_fences are not unsignaled by the consumer, so
the producer must unsignal them.
Change-Id: Icded4c78f63fe2fe22556c6481240c5a50a134a7
Reviewed-on: https://fuchsia-review.googlesource.com/c/fuchsia/+/443335
Reviewed-by: Adam Gousetis <adamgousetis@google.com>
API-Review: Adam Gousetis <adamgousetis@google.com>
Testability-Review: John Bauman <jbauman@google.com>
Commit-Queue: John Bauman <jbauman@google.com>
diff --git a/sdk/fidl/fuchsia.images/image_pipe2.fidl b/sdk/fidl/fuchsia.images/image_pipe2.fidl
index 012cc14..525f7fa 100644
--- a/sdk/fidl/fuchsia.images/image_pipe2.fidl
+++ b/sdk/fidl/fuchsia.images/image_pipe2.fidl
@@ -141,7 +141,9 @@
/// The `acquire_fences` are a set of fences which must all be signaled by the
/// producer before the consumer presents the image.
/// The `release_fences` are set of fences which must all be signaled by the
- /// consumer before it is safe for the producer to free or modify the image.
+ /// consumer before it is safe for the producer to free or modify the image or re-use the
+ /// acquire fences. The acquire fences are not unsignaled by the consumer.
+ ///
/// `presentation_time` specifies the time on or after which the
/// client would like the enqueued operations should take visible effect
/// (light up pixels on the screen), expressed in nanoseconds in the
