Modified: trunk/Source/WebKit/WebProcess/WebPage/MomentumEventDispatcher.cpp (286670 => 286671)
--- trunk/Source/WebKit/WebProcess/WebPage/MomentumEventDispatcher.cpp 2021-12-08 19:46:15 UTC (rev 286670)
+++ trunk/Source/WebKit/WebProcess/WebPage/MomentumEventDispatcher.cpp 2021-12-08 19:58:13 UTC (rev 286671)
@@ -113,15 +113,15 @@
m_currentGesture.accumulatedEventOffset += event.delta();
auto combinedPhase = (event.phase() << 8) | (event.momentumPhase());
- m_currentLogState.latestEventPhase = combinedPhase;
m_currentLogState.totalEventOffset += event.delta().height();
if (!isMomentumEventDuringSyntheticGesture) {
// Log events that we don't block to the generated offsets log as well,
// even though we didn't technically generate them, just passed them through.
- m_currentLogState.latestGeneratedPhase = combinedPhase;
m_currentLogState.totalGeneratedOffset += event.delta().height();
- }
- pushLogEntry();
+ pushLogEntry(combinedPhase, combinedPhase);
+ } else
+ pushLogEntry(0, combinedPhase);
+
#endif
// Consume any normal momentum events while we're inside a synthetic momentum gesture.
@@ -177,9 +177,8 @@
m_dispatcher.internalWheelEvent(m_currentGesture.pageIdentifier, syntheticEvent, m_lastRubberBandableEdges, EventDispatcher::WheelEventOrigin::MomentumEventDispatcher);
#if ENABLE(MOMENTUM_EVENT_DISPATCHER_TEMPORARY_LOGGING)
- m_currentLogState.latestGeneratedPhase = phase;
m_currentLogState.totalGeneratedOffset += appKitAcceleratedDelta.height();
- pushLogEntry();
+ pushLogEntry(phase, 0);
#endif
}
@@ -219,7 +218,7 @@
dispatchSyntheticMomentumEvent(WebWheelEvent::PhaseEnded, { });
#if ENABLE(MOMENTUM_EVENT_DISPATCHER_TEMPORARY_LOGGING)
- RELEASE_LOG(ScrollAnimations, "MomentumEventDispatcher saw momentum end phase with total offset %.1f %.1f, duration %f (event offset would have been %.1f %.1f)", m_currentGesture.currentOffset.width(), m_currentGesture.currentOffset.height(), (MonotonicTime::now() - m_currentGesture.startTime).seconds(), m_currentGesture.accumulatedEventOffset.width(), m_currentGesture.accumulatedEventOffset.height());
+ RELEASE_LOG(ScrollAnimations, "MomentumEventDispatcher saw momentum end phase with total offset %.1f %.1f, duration %f (event offset would have been %.1f %.1f) (tail index %d of %zu)", m_currentGesture.currentOffset.width(), m_currentGesture.currentOffset.height(), (MonotonicTime::now() - m_currentGesture.startTime).seconds(), m_currentGesture.accumulatedEventOffset.width(), m_currentGesture.accumulatedEventOffset.height(), m_currentGesture.currentTailDeltaIndex, m_currentGesture.tailDeltaTable.size());
m_dispatcher.queue().dispatchAfter(1_s, [this] {
flushLog();
});
@@ -294,16 +293,19 @@
WebCore::FloatSize MomentumEventDispatcher::consumeDeltaForCurrentTime()
{
+ WebCore::FloatSize delta;
+
auto animationTime = MonotonicTime::now() - m_currentGesture.startTime;
- auto desiredOffset = offsetAtTime(animationTime);
+ if (animationTime < m_currentGesture.tailStartDelay) {
+ auto desiredOffset = offsetAtTime(animationTime);
+ delta = roundedIntSize(desiredOffset - m_currentGesture.currentOffset);
+ } else {
+ if (m_currentGesture.currentTailDeltaIndex < m_currentGesture.tailDeltaTable.size())
+ delta = -m_currentGesture.tailDeltaTable[m_currentGesture.currentTailDeltaIndex++];
+ else
+ delta = { };
+ }
-#if !ENABLE(MOMENTUM_EVENT_DISPATCHER_PREMATURE_ROUNDING)
- // Intentional delta rounding (but at the end!).
- WebCore::FloatSize delta = roundedIntSize(desiredOffset - m_currentGesture.currentOffset);
-#else
- WebCore::FloatSize delta = desiredOffset - m_currentGesture.currentOffset;
-#endif
-
m_currentGesture.currentOffset += delta;
if (m_currentGesture.initiatingEvent->directionInvertedFromDevice())
@@ -363,27 +365,126 @@
void MomentumEventDispatcher::buildOffsetTableWithInitialDelta(WebCore::FloatSize initialUnacceleratedDelta)
{
-#if ENABLE(MOMENTUM_EVENT_DISPATCHER_PREMATURE_ROUNDING)
- m_currentGesture.carryOffset = { };
-#endif
m_currentGesture.offsetTable.clear();
WebCore::FloatSize accumulatedOffset;
WebCore::FloatSize unacceleratedDelta = initialUnacceleratedDelta;
+ float physicalCurveMultiplier = idealCurveFrameRate / m_currentGesture.accelerationCurve->frameRate();
+ bool inTail = false;
+ WebCore::FloatSize tailCarry;
+
do {
WebCore::FloatSize acceleratedDelta;
std::tie(unacceleratedDelta, acceleratedDelta) = computeNextDelta(unacceleratedDelta);
+ const float tailStartUnacceleratedDelta = 6.f;
+ if (!inTail && std::abs(unacceleratedDelta.width()) < tailStartUnacceleratedDelta && std::abs(unacceleratedDelta.height()) < tailStartUnacceleratedDelta) {
+ inTail = true;
+ m_currentGesture.tailStartDelay = idealCurveFrameInterval * m_currentGesture.offsetTable.size();
+ }
+
+ if (inTail) {
+ auto tailDelta = acceleratedDelta * physicalCurveMultiplier;
+ auto deltaWithCarry = tailDelta + tailCarry;
+ auto quantizedDelta = roundedIntSize(deltaWithCarry);
+ tailCarry = deltaWithCarry - quantizedDelta;
+ m_currentGesture.tailDeltaTable.append(quantizedDelta);
+ }
+
accumulatedOffset += acceleratedDelta;
m_currentGesture.offsetTable.append(accumulatedOffset);
+
} while (std::abs(unacceleratedDelta.width()) > 0.5 || std::abs(unacceleratedDelta.height()) > 0.5);
+ equalizeTailGaps();
+
#if ENABLE(MOMENTUM_EVENT_DISPATCHER_TEMPORARY_LOGGING)
- RELEASE_LOG(ScrollAnimations, "MomentumEventDispatcher built table with %ld frames, initial delta %f %f, distance %f %f (initial delta from last changed event %f %f)", m_currentGesture.offsetTable.size(), initialUnacceleratedDelta.width(), initialUnacceleratedDelta.height(), accumulatedOffset.width(), accumulatedOffset.height(), m_lastActivePhaseDelta.width(), m_lastActivePhaseDelta.height());
+ RELEASE_LOG(ScrollAnimations, "MomentumEventDispatcher built table with %ld frames, %.1f seconds (%ld tail frames, %.1f seconds, starting at %.1f), initial delta %.1f %.1f, distance %.1f %.1f (initial delta from last changed event %.1f %.1f)", m_currentGesture.offsetTable.size(), idealCurveFrameInterval.seconds() * m_currentGesture.offsetTable.size(), m_currentGesture.tailDeltaTable.size(), m_currentGesture.tailDeltaTable.size() * (1.f / m_currentGesture.accelerationCurve->frameRate()), m_currentGesture.tailStartDelay.seconds(), initialUnacceleratedDelta.width(), initialUnacceleratedDelta.height(), accumulatedOffset.width(), accumulatedOffset.height(), m_lastActivePhaseDelta.width(), m_lastActivePhaseDelta.height());
#endif
}
+void MomentumEventDispatcher::equalizeTailGaps()
+{
+ // Sort the deltas up until the first zero to ensure a lack of unexpected
+ // perceptual acceleration, and then inject skipped frames in order to
+ // ensure that frames that have effective scroll movement (non-zero deltas)
+ // are always spaced equally-or-further apart than earlier ones, but
+ // never closer together.
+
+ auto& table = m_currentGesture.tailDeltaTable;
+ size_t initialTableSize = table.size();
+
+ enum Axis { Horizontal, Vertical };
+ Vector<float> deltas[2];
+ unsigned firstZeroIndex[2] = { 0, 0 };
+ deltas[Horizontal].reserveInitialCapacity(initialTableSize);
+ deltas[Vertical].reserveInitialCapacity(initialTableSize);
+ for (unsigned i = 0; i < initialTableSize; i++) {
+ deltas[Horizontal].uncheckedAppend(table[i].width());
+ if (!firstZeroIndex[Horizontal] && !table[i].width())
+ firstZeroIndex[Horizontal] = i;
+
+ deltas[Vertical].uncheckedAppend(table[i].height());
+ if (!firstZeroIndex[Vertical] && !table[i].height())
+ firstZeroIndex[Vertical] = i;
+ }
+
+ if (auto index = firstZeroIndex[Horizontal])
+ std::sort(deltas[Horizontal].begin(), std::next(deltas[Horizontal].begin(), index));
+ if (auto index = firstZeroIndex[Vertical])
+ std::sort(deltas[Vertical].begin(), std::next(deltas[Vertical].begin(), index));
+
+ // GapSize is a count of contiguous frames with zero deltas.
+ typedef unsigned GapSize[2];
+ GapSize minimumGap = { 0, 0 };
+ GapSize currentGap = { 0, 0 };
+ GapSize remainingGapToGenerate = { 0, 0 };
+ unsigned originalTableIndex[2] = { 0, 0 };
+
+ auto takeNextDelta = [&] (uint8_t axis) -> float {
+ if (originalTableIndex[axis] >= initialTableSize)
+ return 0.f;
+
+ if (remainingGapToGenerate[axis]) {
+ --remainingGapToGenerate[axis];
+ ++currentGap[axis];
+ return 0.f;
+ }
+
+ auto value = deltas[axis][originalTableIndex[axis]];
+ if (value) {
+ minimumGap[axis] = std::max(minimumGap[axis], currentGap[axis]);
+ remainingGapToGenerate[axis] = minimumGap[axis] - currentGap[axis];
+ if (remainingGapToGenerate[axis]) {
+ --remainingGapToGenerate[axis];
+ ++currentGap[axis];
+ return 0.f;
+ }
+
+ currentGap[axis] = 0;
+ } else
+ ++currentGap[axis];
+
+ ++originalTableIndex[axis];
+
+ return value;
+ };
+
+ size_t finalTableSize = 0;
+ table.shrink(0);
+
+ while (originalTableIndex[Horizontal] < initialTableSize || originalTableIndex[Vertical] < initialTableSize) {
+ WebCore::FloatSize delta(takeNextDelta(Horizontal), takeNextDelta(Vertical));
+ table.append(delta);
+
+ if (!delta.isZero())
+ finalTableSize = table.size();
+ }
+
+ table.shrink(finalTableSize);
+}
+
static float interpolate(float a, float b, float t)
{
return a + t * (b - a);
@@ -433,28 +534,8 @@
float decayRate = momentumDecayRate(unacceleratedDelta, idealCurveFrameInterval);
unacceleratedDelta.scale(decayRate);
- auto quantizedUnacceleratedDelta = unacceleratedDelta;
-
-#if ENABLE(MOMENTUM_EVENT_DISPATCHER_PREMATURE_ROUNDING)
- // Round and carry.
- int32_t quantizedX = std::round(quantizedUnacceleratedDelta.width());
- int32_t quantizedY = std::round(quantizedUnacceleratedDelta.height());
-
- if (std::abs(quantizedUnacceleratedDelta.width()) < 1 && std::abs(quantizedUnacceleratedDelta.height()) < 1) {
- float deltaXIncludingCarry = quantizedUnacceleratedDelta.width() + m_currentGesture.carryOffset.width();
- float deltaYIncludingCarry = quantizedUnacceleratedDelta.height() + m_currentGesture.carryOffset.height();
-
- // Intentional truncation.
- quantizedX = deltaXIncludingCarry;
- quantizedY = deltaYIncludingCarry;
- m_currentGesture.carryOffset = { deltaXIncludingCarry - quantizedX, deltaYIncludingCarry - quantizedY };
- }
-
- quantizedUnacceleratedDelta = { static_cast<float>(quantizedX), static_cast<float>(quantizedY) };
-#endif
-
// The delta queue operates on pre-acceleration deltas, so insert the new event *before* accelerating.
- didReceiveScrollEventWithInterval(quantizedUnacceleratedDelta, idealCurveFrameInterval);
+ didReceiveScrollEventWithInterval(unacceleratedDelta, idealCurveFrameInterval);
auto accelerateAxis = [&] (HistoricalDeltas& deltas, float value) {
float totalDelta = 0;
@@ -499,8 +580,8 @@
};
WebCore::FloatSize acceleratedDelta(
- accelerateAxis(m_deltaHistoryX, quantizedUnacceleratedDelta.width()),
- accelerateAxis(m_deltaHistoryY, quantizedUnacceleratedDelta.height())
+ accelerateAxis(m_deltaHistoryX, unacceleratedDelta.width()),
+ accelerateAxis(m_deltaHistoryY, unacceleratedDelta.height())
);
#if ENABLE(MOMENTUM_EVENT_DISPATCHER_TEMPORARY_LOGGING)
@@ -512,9 +593,11 @@
#if ENABLE(MOMENTUM_EVENT_DISPATCHER_TEMPORARY_LOGGING)
-void MomentumEventDispatcher::pushLogEntry()
+void MomentumEventDispatcher::pushLogEntry(uint32_t generatedPhase, uint32_t eventPhase)
{
m_currentLogState.time = MonotonicTime::now();
+ m_currentLogState.generatedPhase = generatedPhase;
+ m_currentLogState.eventPhase = eventPhase;
m_log.append(m_currentLogState);
}
@@ -529,7 +612,7 @@
auto startTime = m_log[0].time;
RELEASE_LOG(ScrollAnimations, "MomentumEventDispatcher event log: time,generatedOffset,generatedPhase,eventOffset,eventPhase");
for (const auto& entry : m_log)
- RELEASE_LOG(ScrollAnimations, "MomentumEventDispatcher event log: %f,%f,%d,%f,%d", (entry.time - startTime).seconds(), entry.totalGeneratedOffset, entry.latestGeneratedPhase, entry.totalEventOffset, entry.latestEventPhase);
+ RELEASE_LOG(ScrollAnimations, "MomentumEventDispatcher event log: %f,%f,%d,%f,%d", (entry.time - startTime).seconds(), entry.totalGeneratedOffset, entry.generatedPhase, entry.totalEventOffset, entry.eventPhase);
m_log.clear();
m_currentLogState = { };
