зеркало из https://github.com/mozilla/gecko-dev.git
61 строка
2.3 KiB
C++
61 строка
2.3 KiB
C++
/* -*- 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/. */
|
|
|
|
#ifndef mozilla_layout_ScrollAnimationPhysics_h_
|
|
#define mozilla_layout_ScrollAnimationPhysics_h_
|
|
|
|
#include "mozilla/TimeStamp.h"
|
|
#include "nsPoint.h"
|
|
#include "Units.h"
|
|
|
|
namespace mozilla {
|
|
|
|
class ScrollAnimationPhysics {
|
|
public:
|
|
// Update the animation to have |aDestination| as its new destination.
|
|
// The animation's current position remains unchanged, and the shape
|
|
// of the animation curve is recomputed between the current position
|
|
// and the new destination.
|
|
// This is used in cases where an input event that would cause another
|
|
// animation of this kind is received while this animation is running.
|
|
virtual void Update(const TimeStamp& aTime, const nsPoint& aDestination,
|
|
const nsSize& aCurrentVelocity) = 0;
|
|
|
|
// Shift both the current position and the destination of the animation
|
|
// by |aShiftDelta|. The progress of the animation along its animation
|
|
// curve is unchanged.
|
|
// This is used in cases where the main thread changes the scroll offset
|
|
// (e.g. via scrollBy()) but we want the "momentum" represented by the
|
|
// animation to be preserved.
|
|
virtual void ApplyContentShift(const CSSPoint& aShiftDelta) = 0;
|
|
|
|
// Get the velocity at a point in time in nscoords/sec.
|
|
virtual nsSize VelocityAt(const TimeStamp& aTime) = 0;
|
|
|
|
// Returns the expected scroll position at a given point in time, in app
|
|
// units, relative to the scroll frame.
|
|
virtual nsPoint PositionAt(const TimeStamp& aTime) = 0;
|
|
|
|
virtual bool IsFinished(const TimeStamp& aTime) = 0;
|
|
|
|
virtual ~ScrollAnimationPhysics() = default;
|
|
};
|
|
|
|
// Helper for accelerated wheel deltas. This can be called from the main thread
|
|
// or the APZ Controller thread.
|
|
static inline double ComputeAcceleratedWheelDelta(double aDelta,
|
|
int32_t aCounter,
|
|
int32_t aFactor) {
|
|
if (!aDelta) {
|
|
return aDelta;
|
|
}
|
|
return (aDelta * aCounter * double(aFactor) / 10);
|
|
}
|
|
|
|
} // namespace mozilla
|
|
|
|
#endif // mozilla_layout_ScrollAnimationPhysics_h_
|