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diff --git a/include/input/Resampler.h b/include/input/Resampler.h
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+/**
+ * Copyright 2024 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#pragma once
+
+#include <chrono>
+#include <optional>
+#include <vector>
+
+#include <input/Input.h>
+#include <input/InputTransport.h>
+#include <input/RingBuffer.h>
+#include <utils/Timers.h>
+
+namespace android {
+
+/**
+ * Resampler is an interface for resampling MotionEvents. Every resampling implementation
+ * must use this interface to enable resampling inside InputConsumer's logic.
+ */
+struct Resampler {
+    virtual ~Resampler() = default;
+
+    /**
+     * Tries to resample motionEvent at frameTime. The provided frameTime must be greater than
+     * the latest sample time of motionEvent. It is not guaranteed that resampling occurs at
+     * frameTime. Interpolation may occur is futureSample is available. Otherwise, motionEvent
+     * may be resampled by another method, or not resampled at all. Furthermore, it is the
+     * implementer's responsibility to guarantee the following:
+     * - If resampling occurs, a single additional sample should be added to motionEvent. That is,
+     * if motionEvent had N samples before being passed to Resampler, then it will have N + 1
+     * samples by the end of the resampling. No other field of motionEvent should be modified.
+     * - If resampling does not occur, then motionEvent must not be modified in any way.
+     */
+    virtual void resampleMotionEvent(std::chrono::nanoseconds frameTime, MotionEvent& motionEvent,
+                                     const InputMessage* futureSample) = 0;
+
+    /**
+     * Returns resample latency. Resample latency is the time difference between frame time and
+     * resample time. More precisely, let frameTime and resampleTime be two timestamps, and
+     * frameTime > resampleTime. Resample latency is defined as frameTime - resampleTime.
+     */
+    virtual std::chrono::nanoseconds getResampleLatency() const = 0;
+};
+
+class LegacyResampler final : public Resampler {
+public:
+    /**
+     * Tries to resample `motionEvent` at `frameTime` by adding a resampled sample at the end of
+     * `motionEvent` with eventTime equal to `resampleTime` and pointer coordinates determined by
+     * linear interpolation or linear extrapolation. An earlier `resampleTime` will be used if
+     * extrapolation takes place and `resampleTime` is too far in the future. If `futureSample` is
+     * not null, interpolation will occur. If `futureSample` is null and there is enough historical
+     * data, LegacyResampler will extrapolate. Otherwise, no resampling takes place and
+     * `motionEvent` is unmodified.
+     */
+    void resampleMotionEvent(std::chrono::nanoseconds frameTime, MotionEvent& motionEvent,
+                             const InputMessage* futureSample) override;
+
+    std::chrono::nanoseconds getResampleLatency() const override;
+
+private:
+    struct Pointer {
+        PointerProperties properties;
+        PointerCoords coords;
+    };
+
+    struct Sample {
+        std::chrono::nanoseconds eventTime;
+        std::vector<Pointer> pointers;
+
+        std::vector<PointerCoords> asPointerCoords() const {
+            std::vector<PointerCoords> pointersCoords;
+            for (const Pointer& pointer : pointers) {
+                pointersCoords.push_back(pointer.coords);
+            }
+            return pointersCoords;
+        }
+    };
+
+    /**
+     * Keeps track of the previous MotionEvent deviceId to enable comparison between the previous
+     * and the current deviceId.
+     */
+    std::optional<DeviceId> mPreviousDeviceId;
+
+    /**
+     * Up to two latest samples from MotionEvent. Updated every time resampleMotionEvent is called.
+     * Note: We store up to two samples in order to simplify the implementation. Although,
+     * calculations are possible with only one previous sample.
+     */
+    RingBuffer<Sample> mLatestSamples{/*capacity=*/2};
+
+    /**
+     * Adds up to mLatestSamples.capacity() of motionEvent's latest samples to mLatestSamples. If
+     * motionEvent has fewer samples than mLatestSamples.capacity(), then the available samples are
+     * added to mLatestSamples.
+     */
+    void updateLatestSamples(const MotionEvent& motionEvent);
+
+    static Sample messageToSample(const InputMessage& message);
+
+    /**
+     * Checks if auxiliary sample has the same pointer properties of target sample. That is,
+     * auxiliary pointer IDs must appear in the same order as target pointer IDs, their toolType
+     * must match and be resampleable.
+     */
+    static bool pointerPropertiesResampleable(const Sample& target, const Sample& auxiliary);
+
+    /**
+     * Checks if there are necessary conditions to interpolate. For example, interpolation cannot
+     * take place if samples are too far apart in time. mLatestSamples must have at least one sample
+     * when canInterpolate is invoked.
+     */
+    bool canInterpolate(const InputMessage& futureSample) const;
+
+    /**
+     * Returns a sample interpolated between the latest sample of mLatestSamples and futureSample,
+     * if the conditions from canInterpolate are satisfied. Otherwise, returns nullopt.
+     * mLatestSamples must have at least one sample when attemptInterpolation is called.
+     */
+    std::optional<Sample> attemptInterpolation(std::chrono::nanoseconds resampleTime,
+                                               const InputMessage& futureSample) const;
+
+    /**
+     * Checks if there are necessary conditions to extrapolate. That is, there are at least two
+     * samples in mLatestSamples, and delta is bounded within a time interval.
+     */
+    bool canExtrapolate() const;
+
+    /**
+     * Returns a sample extrapolated from the two samples of mLatestSamples, if the conditions from
+     * canExtrapolate are satisfied. The returned sample either has eventTime equal to resampleTime,
+     * or an earlier time if resampleTime is too far in the future. If canExtrapolate returns false,
+     * this function returns nullopt.
+     */
+    std::optional<Sample> attemptExtrapolation(std::chrono::nanoseconds resampleTime) const;
+
+    inline static void addSampleToMotionEvent(const Sample& sample, MotionEvent& motionEvent);
+};
+} // namespace android