elastic_overscroll_controller.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.

#include "third_party/blink/renderer/platform/widget/input/elastic_overscroll_controller.h"

#include <math.h>

#include <algorithm>

#include "base/functional/bind.h"
#include "build/build_config.h"
#include "cc/input/input_handler.h"
#include "third_party/blink/renderer/platform/widget/input/elastic_overscroll_controller_bezier.h"
#include "third_party/blink/renderer/platform/widget/input/elastic_overscroll_controller_exponential.h"
#include "ui/base/ui_base_features.h"
#include "ui/events/types/scroll_types.h"
#include "ui/gfx/geometry/vector2d_conversions.h"

/*
 * Copyright (C) 2011 Apple Inc. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS''
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
 * THE POSSIBILITY OF SUCH DAMAGE.
 */

namespace blink {

namespace {
constexpr double kScrollVelocityZeroingTimeout = …;
constexpr double kRubberbandMinimumRequiredDeltaBeforeStretch = …;

#if BUILDFLAG(IS_ANDROID)
// On android, overscroll should not occur if the scroller is not scrollable in
// the overscrolled direction.
constexpr bool kOverscrollNonScrollableDirection = false;
#else   // BUILDFLAG(IS_ANDROID)
// On other platforms, overscroll can occur even if the scroller is not
// scrollable.
constexpr bool kOverscrollNonScrollableDirection = …;
#endif  // BUILDFLAG(IS_ANDROID)

}  // namespace

ElasticOverscrollController::ElasticOverscrollController(
    cc::ScrollElasticityHelper* helper)
    : … { … }

std::unique_ptr<ElasticOverscrollController>
ElasticOverscrollController::Create(cc::ScrollElasticityHelper* helper) { … }

void ElasticOverscrollController::ObserveRealScrollBegin(bool enter_momentum,
                                                         bool leave_momentum) { … }

void ElasticOverscrollController::ObserveScrollUpdate(
    const gfx::Vector2dF& event_delta,
    const gfx::Vector2dF& unused_scroll_delta,
    const base::TimeTicks& event_timestamp,
    const cc::OverscrollBehavior overscroll_behavior,
    bool has_momentum) { … }

void ElasticOverscrollController::ObserveRealScrollEnd(
    const base::TimeTicks event_timestamp) { … }

void ElasticOverscrollController::ObserveGestureEventAndResult(
    const WebGestureEvent& gesture_event,
    const cc::InputHandlerScrollResult& scroll_result) { … }

void ElasticOverscrollController::UpdateVelocity(
    const gfx::Vector2dF& event_delta,
    const base::TimeTicks& event_timestamp) { … }

void ElasticOverscrollController::Overscroll(
    const gfx::Vector2dF& overscroll_delta) { … }

void ElasticOverscrollController::EnterStateInactive() { … }

void ElasticOverscrollController::EnterStateMomentumAnimated(
    const base::TimeTicks& triggering_event_timestamp) { … }

void ElasticOverscrollController::Animate(base::TimeTicks time) { … }

bool ElasticOverscrollController::PinnedHorizontally(float direction) const { … }

bool ElasticOverscrollController::PinnedVertically(float direction) const { … }

bool ElasticOverscrollController::CanScrollHorizontally() const { … }

bool ElasticOverscrollController::CanScrollVertically() const { … }

void ElasticOverscrollController::ReconcileStretchAndScroll() { … }

}  // namespace blink
chromium/third_party/blink/renderer/platform/widget/input/elastic_overscroll_controller.cc
