https://bugs.webkit.org/show_bug.cgi?id=223847
Reviewed by Sam Weinig.
Future work will allow DisplayRefreshMonitorClients to request different frame rates, which
are whole fractions of the display's nominal refresh rate. These various frame rate requests
flow up through the DisplayRefreshMonitors, and in WebKit2, up through IPC to the
per-display DisplayLink which may even service multiple processes.
For power reasons, we don't want to trigger display refresh notifications down the chain at
the highest possible frequency; at various stages of propagation the rate might be halved if
that's necessary for downstream clients.
To make this frequency splitting logic simple, this patch introduces DisplayUpdate, which
represents an update of the display, and contains data about it in the form of a numerator
is the frame index, and the denominator is the nominal frame rate. Frame index wraps to zero
every second.
For example, a 60Hz display will generate display refreshes with DisplayUpdates which
sequentially will be { 0, 60 }, { 1, 60 }, { 2, 60 } ... { 59, 60 }, { 0, 60 }. The
zeroth frame is at some arbitrary time and not aligned with wallclock time.
Thus a client with a 30Hz update requirement can simply ignore every odd-numbered frame, and
a client downstream from it with a 15Hz requirement, which only receives those even-numbered
frames, still has enough information to compute which frames to ignore.
Classes which are sources of callbacks for DisplayRefreshMonitor need to generate these
DisplayUpdates; that includes the various platform DisplayRefreshMonitor subclasses in
WebCore, and those in WebKit that live in the UI process and trigger updates over IPC.
Source/WebCore:
* Sources.txt:
* WebCore.xcodeproj/project.pbxproj:
* loader/EmptyClients.cpp:
* platform/graphics/AnimationFrameRate.cpp:
* platform/graphics/AnimationFrameRate.h:
* platform/graphics/DisplayRefreshMonitor.cpp:
(WebCore::DisplayRefreshMonitor::displayLinkFired):
(WebCore::DisplayRefreshMonitor::dispatchDisplayDidRefresh):
(WebCore::DisplayRefreshMonitor::displayDidRefresh):
* platform/graphics/DisplayRefreshMonitor.h:
* platform/graphics/DisplayRefreshMonitorManager.cpp:
(WebCore::DisplayRefreshMonitorManager::displayWasUpdated):
* platform/graphics/DisplayRefreshMonitorManager.h:
* platform/graphics/DisplayUpdate.cpp: Copied from Source/WebCore/platform/graphics/win/DisplayRefreshMonitorWin.h.
(WebCore::operator<<):
* platform/graphics/DisplayUpdate.h: Copied from Source/WebCore/platform/graphics/gtk/DisplayRefreshMonitorGtk.h.
(WebCore::DisplayUpdate::didUpdate):
(WebCore::DisplayUpdate::encode const):
(WebCore::DisplayUpdate::decode):
* platform/graphics/gtk/DisplayRefreshMonitorGtk.cpp: Assume a 60fps refresh rate but this code
should probably use gdk_frame_clock_get_refresh_info() to get the correct rate.
(WebCore::onFrameClockUpdate):
(WebCore::DisplayRefreshMonitorGtk::displayLinkCallbackFired):
(WebCore::DisplayRefreshMonitorGtk::startNotificationMechanism):
* platform/graphics/gtk/DisplayRefreshMonitorGtk.h:
* platform/graphics/ios/DisplayRefreshMonitorIOS.h:
* platform/graphics/ios/DisplayRefreshMonitorIOS.mm:
(-[WebDisplayLinkHandler initWithMonitor:]):
(-[WebDisplayLinkHandler handleDisplayLink:]):
(WebCore::DisplayRefreshMonitorIOS::displayLinkCallbackFired):
(WebCore::DisplayRefreshMonitorIOS::startNotificationMechanism):
(-[WebDisplayLinkHandler setPreferredFramesPerSecond:]): Deleted.
* platform/graphics/mac/LegacyDisplayRefreshMonitorMac.cpp:
(WebCore::displayLinkCallback):
(WebCore::LegacyDisplayRefreshMonitorMac::displayLinkCallbackFired):
(WebCore::LegacyDisplayRefreshMonitorMac::dispatchDisplayDidRefresh):
(WebCore::LegacyDisplayRefreshMonitorMac::nominalFramesPerSecondFromDisplayLink):
(WebCore::LegacyDisplayRefreshMonitorMac::startNotificationMechanism):
* platform/graphics/mac/LegacyDisplayRefreshMonitorMac.h:
(WebCore::LegacyDisplayRefreshMonitorMac::currentUpdate const):
* platform/graphics/win/DisplayRefreshMonitorWin.cpp:
(WebCore::DisplayRefreshMonitorWin::DisplayRefreshMonitorWin):
(WebCore::DisplayRefreshMonitorWin::displayLinkCallbackFired):
* platform/graphics/win/DisplayRefreshMonitorWin.h:
Source/WebKit:
* Shared/CoordinatedGraphics/threadedcompositor/ThreadedDisplayRefreshMonitor.cpp:
(WebKit::ThreadedDisplayRefreshMonitor::invalidate):
(WebKit::ThreadedDisplayRefreshMonitor::displayRefreshCallback):
(WebKit::ThreadedDisplayRefreshMonitor::ThreadedDisplayRefreshMonitor): Deleted.
* Shared/CoordinatedGraphics/threadedcompositor/ThreadedDisplayRefreshMonitor.h:
* UIProcess/mac/DisplayLink.cpp:
(WebKit::DisplayLink::addObserver):
(WebKit::DisplayLink::notifyObserversDisplayWasRefreshed):
* UIProcess/mac/DisplayLink.h:
* WebProcess/WebPage/EventDispatcher.cpp:
(WebKit::EventDispatcher::displayWasRefreshed):
* WebProcess/WebPage/EventDispatcher.h:
* WebProcess/WebPage/EventDispatcher.messages.in:
* WebProcess/WebPage/RemoteLayerTree/RemoteLayerTreeDisplayRefreshMonitor.h:
* WebProcess/WebPage/RemoteLayerTree/RemoteLayerTreeDisplayRefreshMonitor.mm:
(WebKit::RemoteLayerTreeDisplayRefreshMonitor::RemoteLayerTreeDisplayRefreshMonitor):
(WebKit::RemoteLayerTreeDisplayRefreshMonitor::setPreferredFramesPerSecond):
(WebKit::RemoteLayerTreeDisplayRefreshMonitor::didUpdateLayers):
* WebProcess/WebPage/mac/DisplayRefreshMonitorMac.cpp:
(WebKit::DisplayRefreshMonitorMac::dispatchDisplayDidRefresh):
* WebProcess/WebPage/mac/DisplayRefreshMonitorMac.h:
* WebProcess/WebProcess.cpp:
(WebKit::WebProcess::displayWasRefreshed):
* WebProcess/WebProcess.h:
* WebProcess/WebProcess.messages.in:
Canonical link: https://commits.webkit.org/235866@main
git-svn-id: https://svn.webkit.org/repository/webkit/trunk@275163 268f45cc-cd09-0410-ab3c-d52691b4dbfc
d969d5d1ca