BufferQueue: Add NATIVE_WINDOW_BUFFER_AGE query
Adds a NATIVE_WINDOW_BUFFER_AGE query, which returns the age of the
contents of the most recently dequeued buffer as the number of frames
that have elapsed since it was last queued.
Change-Id: Ib6fd62945cb62d1e60133a65beee510363218a23
(cherry picked from commit 49f810c72df8d1d64128e376757079825c8decd4)
diff --git a/libs/gui/BufferQueueProducer.cpp b/libs/gui/BufferQueueProducer.cpp
index 86e45c8..b8df436 100644
--- a/libs/gui/BufferQueueProducer.cpp
+++ b/libs/gui/BufferQueueProducer.cpp
@@ -337,10 +337,18 @@
mSlots[found].mEglDisplay = EGL_NO_DISPLAY;
mSlots[found].mEglFence = EGL_NO_SYNC_KHR;
mSlots[found].mFence = Fence::NO_FENCE;
+ mCore->mBufferAge = 0;
returnFlags |= BUFFER_NEEDS_REALLOCATION;
+ } else {
+ // We add 1 because that will be the frame number when this buffer
+ // is queued
+ mCore->mBufferAge =
+ mCore->mFrameCounter + 1 - mSlots[found].mFrameNumber;
}
+ BQ_LOGV("dequeueBuffer: setting buffer age to %llu", mCore->mBufferAge);
+
if (CC_UNLIKELY(mSlots[found].mFence == NULL)) {
BQ_LOGE("dequeueBuffer: about to return a NULL fence - "
"slot=%d w=%d h=%d format=%u",
@@ -784,6 +792,13 @@
case NATIVE_WINDOW_DEFAULT_DATASPACE:
value = static_cast<int32_t>(mCore->mDefaultBufferDataSpace);
break;
+ case NATIVE_WINDOW_BUFFER_AGE:
+ if (mCore->mBufferAge > INT32_MAX) {
+ value = 0;
+ } else {
+ value = static_cast<int32_t>(mCore->mBufferAge);
+ }
+ break;
default:
return BAD_VALUE;
}