/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#include "SmoothMsdScrollAnimation.h"
#include "AsyncPanZoomController.h"
namespace mozilla {
namespace layers {
SmoothMsdScrollAnimation::SmoothMsdScrollAnimation(
AsyncPanZoomController& aApzc,
const CSSPoint& aInitialPosition,
const CSSPoint& aInitialVelocity,
const CSSPoint& aDestination,
double aSpringConstant,
double aDampingRatio,
ScrollSnapTargetIds&& aSnapTargetIds,
ScrollTriggeredByScript aTriggeredByScript)
: mApzc(aApzc),
mXAxisModel(aInitialPosition.x, aDestination.x, aInitialVelocity.x,
aSpringConstant, aDampingRatio),
mYAxisModel(aInitialPosition.y, aDestination.y, aInitialVelocity.y,
aSpringConstant, aDampingRatio),
mSnapTargetIds(std::move(aSnapTargetIds)),
mTriggeredByScript(aTriggeredByScript) {}
bool SmoothMsdScrollAnimation::DoSample(FrameMetrics& aFrameMetrics,
const TimeDuration& aDelta) {
CSSToParentLayerScale zoom(aFrameMetrics.GetZoom());
if (zoom == CSSToParentLayerScale(0)) {
return false;
}
CSSPoint oneParentLayerPixel =
ParentLayerPoint(1, 1) / aFrameMetrics.GetZoom();
if (mXAxisModel.IsFinished(oneParentLayerPixel.x) &&
mYAxisModel.IsFinished(oneParentLayerPixel.y)) {
// Set the scroll offset to the exact destination. If we allow the scroll
// offset to end up being a bit off from the destination, we can get
// artefacts like "scroll to the next snap point in this direction"
// scrolling to the snap point we're already supposed to be at.
mApzc.ClampAndSetVisualScrollOffset(
CSSPoint(mXAxisModel.GetDestination(), mYAxisModel.GetDestination()));
return false;
}
mXAxisModel.Simulate(aDelta);
mYAxisModel.Simulate(aDelta);
CSSPoint position =
CSSPoint(mXAxisModel.GetPosition(), mYAxisModel.GetPosition());
CSSPoint css_velocity =
CSSPoint(mXAxisModel.GetVelocity(), mYAxisModel.GetVelocity());
// Convert from pixels/second to pixels/ms
ParentLayerPoint velocity =
ParentLayerPoint(css_velocity.x, css_velocity.y) / 1000.0f;
// Keep the velocity updated for the Axis class so that any animations
// chained off of the smooth scroll will inherit it.
if (mXAxisModel.IsFinished(oneParentLayerPixel.x)) {
mApzc.mX.SetVelocity(0);
}
else {
mApzc.mX.SetVelocity(velocity.x);
}
if (mYAxisModel.IsFinished(oneParentLayerPixel.y)) {
mApzc.mY.SetVelocity(0);
}
else {
mApzc.mY.SetVelocity(velocity.y);
}
// If we overscroll, hand off to a fling animation that will complete the
// spring back.
ParentLayerPoint displacement =
(position - aFrameMetrics.GetVisualScrollOffset()) * zoom;
ParentLayerPoint overscroll;
ParentLayerPoint adjustedOffset;
mApzc.mX.AdjustDisplacement(displacement.x, adjustedOffset.x, overscroll.x);
mApzc.mY.AdjustDisplacement(displacement.y, adjustedOffset.y, overscroll.y);
mApzc.ScrollBy(adjustedOffset / zoom);
bool reachedEndOfScrollRange = !IsZero(overscroll / zoom);
// Do not hand off a smooth scroll animation to an ancestor APZC,
// nor allow it to cause overscroll.
return !reachedEndOfScrollRange;
}
void SmoothMsdScrollAnimation::SetDestination(
const CSSPoint& aNewDestination, ScrollSnapTargetIds&& aSnapTargetIds,
ScrollTriggeredByScript aTriggeredByScript) {
mXAxisModel.SetDestination(aNewDestination.x);
mYAxisModel.SetDestination(aNewDestination.y);
mSnapTargetIds = std::move(aSnapTargetIds);
mTriggeredByScript = aTriggeredByScript;
}
CSSPoint SmoothMsdScrollAnimation::GetDestination()
const {
return CSSPoint(mXAxisModel.GetDestination(), mYAxisModel.GetDestination());
}
SmoothMsdScrollAnimation*
SmoothMsdScrollAnimation::AsSmoothMsdScrollAnimation() {
return this;
}
}
// namespace layers
}
// namespace mozilla
