| /* |
| * Copyright (C) 2021 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. |
| */ |
| |
| #pragma once |
| |
| #if ENABLE(MOMENTUM_EVENT_DISPATCHER) |
| |
| #include <WebCore/FloatSize.h> |
| #include <wtf/text/WTFString.h> |
| |
| namespace IPC { |
| class Decoder; |
| class Encoder; |
| } |
| |
| namespace WebKit { |
| |
| class NativeWebWheelEvent; |
| |
| class ScrollingAccelerationCurve { |
| public: |
| ScrollingAccelerationCurve(float gainLinear, float gainParabolic, float gainCubic, float gainQuartic, float tangentSpeedLinear, float tangentSpeedParabolicRoot, float resolution, float frameRate); |
| |
| static std::optional<ScrollingAccelerationCurve> fromNativeWheelEvent(const NativeWebWheelEvent&); |
| |
| static ScrollingAccelerationCurve interpolate(const ScrollingAccelerationCurve& from, const ScrollingAccelerationCurve& to, float amount); |
| |
| float accelerationFactor(float); |
| float frameRate() const { return m_parameters.frameRate; } |
| |
| void encode(IPC::Encoder&) const; |
| static std::optional<ScrollingAccelerationCurve> decode(IPC::Decoder&); |
| |
| bool operator==(const ScrollingAccelerationCurve& other) const |
| { |
| return m_parameters.gainLinear == other.m_parameters.gainLinear |
| && m_parameters.gainParabolic == other.m_parameters.gainParabolic |
| && m_parameters.gainCubic == other.m_parameters.gainCubic |
| && m_parameters.gainQuartic == other.m_parameters.gainQuartic |
| && m_parameters.tangentSpeedLinear == other.m_parameters.tangentSpeedLinear |
| && m_parameters.tangentSpeedParabolicRoot == other.m_parameters.tangentSpeedParabolicRoot |
| && m_parameters.resolution == other.m_parameters.resolution |
| && m_parameters.frameRate == other.m_parameters.frameRate; |
| } |
| |
| bool operator!=(const ScrollingAccelerationCurve& other) const { return !(*this == other); } |
| |
| private: |
| friend TextStream& operator<<(TextStream&, const ScrollingAccelerationCurve&); |
| |
| void computeIntermediateValuesIfNeeded(); |
| |
| float evaluateQuartic(float) const; |
| |
| struct { |
| float gainLinear { 0 }; |
| float gainParabolic { 0 }; |
| float gainCubic { 0 }; |
| float gainQuartic { 0 }; |
| float tangentSpeedLinear { 0 }; |
| float tangentSpeedParabolicRoot { 0 }; |
| |
| // FIXME: Resolution and frame rate are not technically properties |
| // of the curve, just required to use it; they should be plumbed separately. |
| float resolution { 0 }; |
| float frameRate { 0 }; |
| } m_parameters; |
| |
| struct ComputedIntermediateValues { |
| float tangentStartX { 0 }; |
| float tangentSlope { 0 }; |
| float tangentIntercept { 0 }; |
| float falloffStartX { 0 }; |
| float falloffSlope { 0 }; |
| float falloffIntercept { 0 }; |
| }; |
| |
| std::optional<ComputedIntermediateValues> m_intermediates; |
| }; |
| |
| TextStream& operator<<(TextStream&, const ScrollingAccelerationCurve&); |
| |
| } // namespace WebKit |
| |
| #endif // ENABLE(MOMENTUM_EVENT_DISPATCHER) |