mobile_scroller.cc | Explore in Territory

// Copyright 2014 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifdef UNSAFE_BUFFERS_BUILD
// TODO(crbug.com/351564777): Remove this and convert code to safer constructs.
#pragma allow_unsafe_buffers
#endif

#include "ui/events/mobile_scroller.h"

#include <cmath>
#include <ostream>

#include "base/check_op.h"
#include "base/lazy_instance.h"
#include "base/notreached.h"
#include "base/numerics/math_constants.h"

namespace ui {
namespace {

// Default scroll duration from android.widget.Scroller.
const int kDefaultDurationMs = …;

// Default friction constant in android.view.ViewConfiguration.
const float kDefaultFriction = …;

// == std::log(0.78f) / std::log(0.9f)
const float kDecelerationRate = …;

// Tension lines cross at (kInflexion, 1).
const float kInflexion = …;

const float kEpsilon = …;

// Fling scroll is stopped when the scroll position is |kThresholdForFlingEnd|
// pixels or closer from the end.
const float kThresholdForFlingEnd = …;

bool ApproxEquals(float a, float b) { … }

struct ViscosityConstants { … };

struct SplineConstants { … };

float ComputeDeceleration(float friction) { … }

template <typename T>
int Signum(T t) { … }

template <typename T>
T Clamped(T t, T a, T b) { … }

// Leaky to allow access from the impl thread.
base::LazyInstance<ViscosityConstants>::Leaky g_viscosity_constants = …;

base::LazyInstance<SplineConstants>::Leaky g_spline_constants = …;

}  // namespace

MobileScroller::Config::Config()
    : … { … }

MobileScroller::MobileScroller(const Config& config)
    : … { … }

MobileScroller::~MobileScroller() { … }

bool MobileScroller::ComputeScrollOffset(base::TimeTicks time,
                                         gfx::Vector2dF* offset,
                                         gfx::Vector2dF* velocity) { … }

void MobileScroller::StartScroll(float start_x,
                                 float start_y,
                                 float dx,
                                 float dy,
                                 base::TimeTicks start_time) { … }

void MobileScroller::StartScroll(float start_x,
                                 float start_y,
                                 float dx,
                                 float dy,
                                 base::TimeTicks start_time,
                                 base::TimeDelta duration) { … }

void MobileScroller::Fling(float start_x,
                           float start_y,
                           float velocity_x,
                           float velocity_y,
                           float min_x,
                           float max_x,
                           float min_y,
                           float max_y,
                           base::TimeTicks start_time) { … }

void MobileScroller::ExtendDuration(base::TimeDelta extend) { … }

void MobileScroller::SetFinalX(float new_x) { … }

void MobileScroller::SetFinalY(float new_y) { … }

void MobileScroller::AbortAnimation() { … }

void MobileScroller::ForceFinished(bool finished) { … }

bool MobileScroller::IsFinished() const { … }

base::TimeDelta MobileScroller::GetTimePassed() const { … }

base::TimeDelta MobileScroller::GetDuration() const { … }

float MobileScroller::GetCurrX() const { … }

float MobileScroller::GetCurrY() const { … }

float MobileScroller::GetCurrVelocity() const { … }

float MobileScroller::GetCurrVelocityX() const { … }

float MobileScroller::GetCurrVelocityY() const { … }

float MobileScroller::GetStartX() const { … }

float MobileScroller::GetStartY() const { … }

float MobileScroller::GetFinalX() const { … }

float MobileScroller::GetFinalY() const { … }

bool MobileScroller::IsScrollingInDirection(float xvel, float yvel) const { … }

bool MobileScroller::ComputeScrollOffsetInternal(base::TimeTicks time) { … }

void MobileScroller::RecomputeDeltas() { … }

double MobileScroller::GetSplineDeceleration(float velocity) const { … }

base::TimeDelta MobileScroller::GetSplineFlingDuration(float velocity) const { … }

double MobileScroller::GetSplineFlingDistance(float velocity) const { … }

}  // namespace ui
chromium/ui/events/mobile_scroller.cc
