Hi All:
The method onFrameAvailable In FrameBufferSurface.cpp of Android:
------------------------------------------------------------
void FramebufferSurface::onFrameAvailable() {
sp<GraphicBuffer> buf;
sp<Fence> acquireFence;
status_t err = nextBuffer(buf, acquireFence);
if (err != NO_ERROR) {
ALOGE("error latching nnext FramebufferSurface buffer: %s (%d)",
strerror(-err), err);
return;
}
err = mHwc.fbPost(mDisplayType, acquireFence, buf);
if (err != NO_ERROR) {
ALOGE("error posting framebuffer: %d", err);
}
}
-------------------------------------------------------------
fbPost be executed here, but in B2G, the fbPost is executed in
GonkDisplayJB::SwapBuffers, not in
gecko/widget/gonk/libdisplay/FramebufferSurface.cpp
--------------------------------------------------------------
bool
GonkDisplayJB::SwapBuffers(EGLDisplay dpy, EGLSurface sur)
{
StopBootAnimation();
mBootAnimBuffer = nullptr;
// Should be called when composition rendering is complete for a frame.
// Only HWC v1.0 needs this call.
// HWC > v1.0 case, do not call compositionComplete().
// mFBDevice is present only when HWC is v1.0.
if (mFBDevice && mFBDevice->compositionComplete) {
mFBDevice->compositionComplete(mFBDevice);
}
#if ANDROID_VERSION == 17
mList->dpy = dpy;
mList->sur = sur;
#else
mList->outbuf = nullptr;
mList->outbufAcquireFenceFd = -1;
#endif
eglSwapBuffers(dpy, sur);
return Post(mFBSurface->lastHandle, mFBSurface->lastFenceFD);
}
--------------------------------------------------------------
I'm wondering why there's such a difference ?
on my device, the views on screen will be torn, especially when views change
quickly.
But if I move the method {Post(mFBSurface->lastHandle,
mFBSurface->lastFenceFD);} to
gecko/widget/gonk/libdisplay/FramebufferSurface.cpp::onFrameAvailable() , this
problem is resolved.
Any body could explain the reason ? thanks in advance!
_______________________________________________
dev-b2g mailing list
dev-b2g@lists.mozilla.org
https://lists.mozilla.org/listinfo/dev-b2g
