Add multiple pointer support to LegacyResampler with tests

Added multiple pointer support to LegacyResampler and included the
corresponding unit tests to ensure correctness.

Bug: 297226446
Flag: EXEMPT refactor
Test: TEST=libinput_tests; m $TEST && $ANDROID_HOST_OUT/nativetest64/$TEST/$TEST --gtest_filter="ResamplerTest*"
Change-Id: Ib639942c31311dcdcf6d72ed33a4d4476b76fe7f

3 files changed, 619 insertions, 122 deletions

diff --git a/include/input/Resampler.h b/include/input/Resampler.h
index 5980d5d4c4..2892137ae7 100644
--- a/include/input/Resampler.h
+++ b/include/input/Resampler.h
@@ -18,6 +18,7 @@
 
 #include <chrono>
 #include <optional>
+#include <vector>
 
 #include <input/Input.h>
 #include <input/InputTransport.h>
@@ -71,7 +72,15 @@ private:
 
     struct Sample {
         std::chrono::nanoseconds eventTime;
-        Pointer pointer;
+        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;
+        }
     };
 
     /**
@@ -88,12 +97,21 @@ private:
     RingBuffer<Sample> mLatestSamples{/*capacity=*/2};
 
     /**
-     * Adds up to mLatestSamples.capacity() of motionEvent's latest samples to mLatestSamples. (If
+     * 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.)
+     * 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
@@ -125,4 +143,4 @@ private:
 
     inline static void addSampleToMotionEvent(const Sample& sample, MotionEvent& motionEvent);
 };
-} // namespace android
\ No newline at end of file
+} // namespace android
diff --git a/libs/input/Resampler.cpp b/libs/input/Resampler.cpp
index 342f7f557f..a1e6e06784 100644
--- a/libs/input/Resampler.cpp
+++ b/libs/input/Resampler.cpp
@@ -21,6 +21,7 @@
 
 #include <android-base/logging.h>
 #include <android-base/properties.h>
+#include <ftl/enum.h>
 
 #include <input/Resampler.h>
 #include <utils/Timers.h>
@@ -56,6 +57,11 @@ constexpr std::chrono::milliseconds RESAMPLE_MAX_DELTA{20};
 
 constexpr std::chrono::milliseconds RESAMPLE_MAX_PREDICTION{8};
 
+bool canResampleTool(ToolType toolType) {
+    return toolType == ToolType::FINGER || toolType == ToolType::MOUSE ||
+            toolType == ToolType::STYLUS || toolType == ToolType::UNKNOWN;
+}
+
 inline float lerp(float a, float b, float alpha) {
     return a + alpha * (b - a);
 }
@@ -73,21 +79,71 @@ PointerCoords calculateResampledCoords(const PointerCoords& a, const PointerCoor
 
 void LegacyResampler::updateLatestSamples(const MotionEvent& motionEvent) {
     const size_t numSamples = motionEvent.getHistorySize() + 1;
-    for (size_t i = 0; i < numSamples; ++i) {
+    const size_t latestIndex = numSamples - 1;
+    const size_t secondToLatestIndex = (latestIndex > 0) ? (latestIndex - 1) : 0;
+    for (size_t sampleIndex = secondToLatestIndex; sampleIndex < numSamples; ++sampleIndex) {
+        std::vector<Pointer> pointers;
+        const size_t numPointers = motionEvent.getPointerCount();
+        for (size_t pointerIndex = 0; pointerIndex < numPointers; ++pointerIndex) {
+            // getSamplePointerCoords is the vector representation of a getHistorySize by
+            // getPointerCount matrix.
+            const PointerCoords& pointerCoords =
+                    motionEvent.getSamplePointerCoords()[sampleIndex * numPointers + pointerIndex];
+            pointers.push_back(
+                    Pointer{*motionEvent.getPointerProperties(pointerIndex), pointerCoords});
+        }
         mLatestSamples.pushBack(
-                Sample{static_cast<nanoseconds>(motionEvent.getHistoricalEventTime(i)),
-                       Pointer{*motionEvent.getPointerProperties(0),
-                               motionEvent.getSamplePointerCoords()[i]}});
+                Sample{static_cast<nanoseconds>(motionEvent.getHistoricalEventTime(sampleIndex)),
+                       pointers});
+    }
+}
+
+LegacyResampler::Sample LegacyResampler::messageToSample(const InputMessage& message) {
+    std::vector<Pointer> pointers;
+    for (uint32_t i = 0; i < message.body.motion.pointerCount; ++i) {
+        pointers.push_back(Pointer{message.body.motion.pointers[i].properties,
+                                   message.body.motion.pointers[i].coords});
+    }
+    return Sample{static_cast<nanoseconds>(message.body.motion.eventTime), pointers};
+}
+
+bool LegacyResampler::pointerPropertiesResampleable(const Sample& target, const Sample& auxiliary) {
+    if (target.pointers.size() > auxiliary.pointers.size()) {
+        LOG_IF(INFO, debugResampling())
+                << "Not resampled. Auxiliary sample has fewer pointers than target sample.";
+        return false;
     }
+    for (size_t i = 0; i < target.pointers.size(); ++i) {
+        if (target.pointers[i].properties.id != auxiliary.pointers[i].properties.id) {
+            LOG_IF(INFO, debugResampling()) << "Not resampled. Pointer ID mismatch.";
+            return false;
+        }
+        if (target.pointers[i].properties.toolType != auxiliary.pointers[i].properties.toolType) {
+            LOG_IF(INFO, debugResampling()) << "Not resampled. Pointer ToolType mismatch.";
+            return false;
+        }
+        if (!canResampleTool(target.pointers[i].properties.toolType)) {
+            LOG_IF(INFO, debugResampling())
+                    << "Not resampled. Cannot resample "
+                    << ftl::enum_string(target.pointers[i].properties.toolType) << " ToolType.";
+            return false;
+        }
+    }
+    return true;
 }
 
-bool LegacyResampler::canInterpolate(const InputMessage& futureSample) const {
+bool LegacyResampler::canInterpolate(const InputMessage& message) const {
     LOG_IF(FATAL, mLatestSamples.empty())
             << "Not resampled. mLatestSamples must not be empty to interpolate.";
 
     const Sample& pastSample = *(mLatestSamples.end() - 1);
-    const nanoseconds delta =
-            static_cast<nanoseconds>(futureSample.body.motion.eventTime) - pastSample.eventTime;
+    const Sample& futureSample = messageToSample(message);
+
+    if (!pointerPropertiesResampleable(pastSample, futureSample)) {
+        return false;
+    }
+
+    const nanoseconds delta = futureSample.eventTime - pastSample.eventTime;
     if (delta < RESAMPLE_MIN_DELTA) {
         LOG_IF(INFO, debugResampling()) << "Not resampled. Delta is too small: " << delta << "ns.";
         return false;
@@ -104,15 +160,20 @@ std::optional<LegacyResampler::Sample> LegacyResampler::attemptInterpolation(
             << "Not resampled. mLatestSamples must not be empty to interpolate.";
 
     const Sample& pastSample = *(mLatestSamples.end() - 1);
+
     const nanoseconds delta =
             static_cast<nanoseconds>(futureSample.body.motion.eventTime) - pastSample.eventTime;
     const float alpha =
             std::chrono::duration<float, std::milli>(resampleTime - pastSample.eventTime) / delta;
-    const PointerCoords resampledCoords =
-            calculateResampledCoords(pastSample.pointer.coords,
-                                     futureSample.body.motion.pointers[0].coords, alpha);
 
-    return Sample{resampleTime, Pointer{pastSample.pointer.properties, resampledCoords}};
+    std::vector<Pointer> resampledPointers;
+    for (size_t i = 0; i < pastSample.pointers.size(); ++i) {
+        const PointerCoords& resampledCoords =
+                calculateResampledCoords(pastSample.pointers[i].coords,
+                                         futureSample.body.motion.pointers[i].coords, alpha);
+        resampledPointers.push_back(Pointer{pastSample.pointers[i].properties, resampledCoords});
+    }
+    return Sample{resampleTime, resampledPointers};
 }
 
 bool LegacyResampler::canExtrapolate() const {
@@ -124,6 +185,10 @@ bool LegacyResampler::canExtrapolate() const {
     const Sample& pastSample = *(mLatestSamples.end() - 2);
     const Sample& presentSample = *(mLatestSamples.end() - 1);
 
+    if (!pointerPropertiesResampleable(presentSample, pastSample)) {
+        return false;
+    }
+
     const nanoseconds delta = presentSample.eventTime - pastSample.eventTime;
     if (delta < RESAMPLE_MIN_DELTA) {
         LOG_IF(INFO, debugResampling()) << "Not resampled. Delta is too small: " << delta << "ns.";
@@ -160,16 +225,21 @@ std::optional<LegacyResampler::Sample> LegacyResampler::attemptExtrapolation(
     const float alpha =
             std::chrono::duration<float, std::milli>(newResampleTime - pastSample.eventTime) /
             delta;
-    const PointerCoords resampledCoords =
-            calculateResampledCoords(pastSample.pointer.coords, presentSample.pointer.coords,
-                                     alpha);
 
-    return Sample{newResampleTime, Pointer{presentSample.pointer.properties, resampledCoords}};
+    std::vector<Pointer> resampledPointers;
+    for (size_t i = 0; i < presentSample.pointers.size(); ++i) {
+        const PointerCoords& resampledCoords =
+                calculateResampledCoords(pastSample.pointers[i].coords,
+                                         presentSample.pointers[i].coords, alpha);
+        resampledPointers.push_back(Pointer{presentSample.pointers[i].properties, resampledCoords});
+    }
+    return Sample{newResampleTime, resampledPointers};
 }
 
 inline void LegacyResampler::addSampleToMotionEvent(const Sample& sample,
                                                     MotionEvent& motionEvent) {
-    motionEvent.addSample(sample.eventTime.count(), &sample.pointer.coords, motionEvent.getId());
+    motionEvent.addSample(sample.eventTime.count(), sample.asPointerCoords().data(),
+                          motionEvent.getId());
 }
 
 void LegacyResampler::resampleMotionEvent(nanoseconds resampleTime, MotionEvent& motionEvent,
diff --git a/libs/input/tests/Resampler_test.cpp b/libs/input/tests/Resampler_test.cpp
index 135f8b41a2..b372c0b183 100644
--- a/libs/input/tests/Resampler_test.cpp
+++ b/libs/input/tests/Resampler_test.cpp
@@ -59,6 +59,9 @@ Pointer::operator PointerCoords() const {
 struct InputSample {
     std::chrono::milliseconds eventTime{0};
     std::vector<Pointer> pointers{};
+
+    explicit InputSample(std::chrono::milliseconds eventTime, const std::vector<Pointer>& pointers)
+          : eventTime{eventTime}, pointers{pointers} {}
     /**
      * Converts from InputSample to InputMessage. Enables calling LegacyResampler methods only with
      * the relevant data for tests.
@@ -73,6 +76,7 @@ InputSample::operator InputMessage() const {
     message.body.motion.eventTime = static_cast<std::chrono::nanoseconds>(eventTime).count();
     message.body.motion.source = AINPUT_SOURCE_CLASS_POINTER;
     message.body.motion.downTime = 0;
+
     const uint32_t pointerCount = message.body.motion.pointerCount;
     for (uint32_t i = 0; i < pointerCount; ++i) {
         message.body.motion.pointers[i].properties.id = pointers[i].id;
@@ -132,14 +136,6 @@ protected:
 
     std::unique_ptr<Resampler> mResampler;
 
-    MotionEvent buildMotionEvent(const int32_t action, const nsecs_t eventTime,
-                                 const std::vector<PointerBuilder>& pointers);
-
-    InputMessage createMessage(const uint32_t pointerCount, const nsecs_t eventTime,
-                               const int32_t action,
-                               const std::vector<PointerProperties>& properties,
-                               const std::vector<PointerCoords>& coords);
-
     /**
      * Checks that beforeCall and afterCall are equal except for the mutated attributes by addSample
      * member function.
@@ -153,42 +149,14 @@ protected:
      * Asserts the MotionEvent is resampled by checking an increment in history size and that the
      * resampled coordinates are near the expected ones.
      */
-    void assertMotionEventIsResampledAndCoordsNear(const MotionEvent& original,
-                                                   const MotionEvent& resampled,
-                                                   const PointerCoords& expectedCoords);
+    void assertMotionEventIsResampledAndCoordsNear(
+            const MotionEvent& original, const MotionEvent& resampled,
+            const std::vector<PointerCoords>& expectedCoords);
 
     void assertMotionEventIsNotResampled(const MotionEvent& original,
                                          const MotionEvent& notResampled);
 };
 
-MotionEvent ResamplerTest::buildMotionEvent(const int32_t action, const nsecs_t eventTime,
-                                            const std::vector<PointerBuilder>& pointerBuilders) {
-    MotionEventBuilder motionEventBuilder = MotionEventBuilder(action, AINPUT_SOURCE_CLASS_POINTER)
-                                                    .downTime(0)
-                                                    .eventTime(eventTime);
-    for (const PointerBuilder& pointerBuilder : pointerBuilders) {
-        motionEventBuilder.pointer(pointerBuilder);
-    }
-    return motionEventBuilder.build();
-}
-
-InputMessage ResamplerTest::createMessage(const uint32_t pointerCount, const nsecs_t eventTime,
-                                          const int32_t action,
-                                          const std::vector<PointerProperties>& properties,
-                                          const std::vector<PointerCoords>& coords) {
-    InputMessage message;
-    message.header.type = InputMessage::Type::MOTION;
-    message.body.motion.pointerCount = pointerCount;
-    message.body.motion.eventTime = eventTime;
-    message.body.motion.source = AINPUT_SOURCE_CLASS_POINTER;
-    message.body.motion.downTime = 0;
-    for (uint32_t i = 0; i < pointerCount; ++i) {
-        message.body.motion.pointers[i].properties = properties[i];
-        message.body.motion.pointers[i].coords = coords[i];
-    }
-    return message;
-}
-
 void ResamplerTest::assertMotionEventMetaDataDidNotMutate(const MotionEvent& beforeCall,
                                                           const MotionEvent& afterCall) {
     EXPECT_EQ(beforeCall.getDeviceId(), afterCall.getDeviceId());
@@ -207,18 +175,29 @@ void ResamplerTest::assertMotionEventMetaDataDidNotMutate(const MotionEvent& bef
     EXPECT_EQ(beforeCall.getDisplayId(), afterCall.getDisplayId());
 }
 
-void ResamplerTest::assertMotionEventIsResampledAndCoordsNear(const MotionEvent& original,
-                                                              const MotionEvent& resampled,
-                                                              const PointerCoords& expectedCoords) {
+void ResamplerTest::assertMotionEventIsResampledAndCoordsNear(
+        const MotionEvent& original, const MotionEvent& resampled,
+        const std::vector<PointerCoords>& expectedCoords) {
     assertMotionEventMetaDataDidNotMutate(original, resampled);
+
     const size_t originalSampleSize = original.getHistorySize() + 1;
     const size_t resampledSampleSize = resampled.getHistorySize() + 1;
     EXPECT_EQ(originalSampleSize + 1, resampledSampleSize);
-    const PointerCoords& resampledCoords =
-            resampled.getSamplePointerCoords()[resampled.getHistorySize()];
-    EXPECT_TRUE(resampledCoords.isResampled);
-    EXPECT_NEAR(expectedCoords.getX(), resampledCoords.getX(), EPSILON);
-    EXPECT_NEAR(expectedCoords.getY(), resampledCoords.getY(), EPSILON);
+
+    const size_t numPointers = resampled.getPointerCount();
+    const size_t beginLatestSample = resampledSampleSize - 1;
+    for (size_t i = 0; i < numPointers; ++i) {
+        SCOPED_TRACE(i);
+        EXPECT_EQ(original.getPointerId(i), resampled.getPointerId(i));
+        EXPECT_EQ(original.getToolType(i), resampled.getToolType(i));
+
+        const PointerCoords& resampledCoords =
+                resampled.getSamplePointerCoords()[beginLatestSample * numPointers + i];
+
+        EXPECT_TRUE(resampledCoords.isResampled);
+        EXPECT_NEAR(expectedCoords[i].getX(), resampledCoords.getX(), EPSILON);
+        EXPECT_NEAR(expectedCoords[i].getY(), resampledCoords.getY(), EPSILON);
+    }
 }
 
 void ResamplerTest::assertMotionEventIsNotResampled(const MotionEvent& original,
@@ -233,7 +212,7 @@ TEST_F(ResamplerTest, NonResampledAxesArePreserved) {
     constexpr float TOUCH_MAJOR_VALUE = 1.0f;
 
     MotionEvent motionEvent =
-            InputStream{{{5ms, {{.id = 0, .x = 1.0f, .y = 1.0f, .isResampled = false}}}},
+            InputStream{{InputSample{5ms, {{.id = 0, .x = 1.0f, .y = 1.0f, .isResampled = false}}}},
                         AMOTION_EVENT_ACTION_MOVE};
 
     constexpr std::chrono::nanoseconds eventTime{10ms};
@@ -255,34 +234,40 @@ TEST_F(ResamplerTest, NonResampledAxesArePreserved) {
     EXPECT_EQ(motionEvent.getTouchMajor(0), TOUCH_MAJOR_VALUE);
 
     assertMotionEventIsResampledAndCoordsNear(originalMotionEvent, motionEvent,
-                                              Pointer{.id = 0,
-                                                      .x = 2.2f,
-                                                      .y = 2.4f,
-                                                      .isResampled = true});
+                                              {Pointer{.id = 0,
+                                                       .x = 2.2f,
+                                                       .y = 2.4f,
+                                                       .isResampled = true}});
 }
 
 TEST_F(ResamplerTest, SinglePointerNotEnoughDataToResample) {
     MotionEvent motionEvent =
-            InputStream{{{5ms, {{.id = 0, .x = 1.0f, .y = 1.0f, .isResampled = false}}}},
-                        AMOTION_EVENT_ACTION_MOVE,
-                        .deviceId = 0};
+            InputStream{{InputSample{5ms, {{.id = 0, .x = 1.0f, .y = 1.0f, .isResampled = false}}}},
+                        AMOTION_EVENT_ACTION_MOVE};
+
     const MotionEvent originalMotionEvent = motionEvent;
-    mResampler->resampleMotionEvent(11ms, motionEvent, nullptr);
+
+    mResampler->resampleMotionEvent(11ms, motionEvent, /*futureSample=*/nullptr);
+
     assertMotionEventIsNotResampled(originalMotionEvent, motionEvent);
 }
 
 TEST_F(ResamplerTest, SinglePointerDifferentDeviceIdBetweenMotionEvents) {
     MotionEvent motionFromFirstDevice =
-            InputStream{{{4ms, {{.id = 0, .x = 1.0f, .y = 1.0f, .isResampled = false}}},
-                         {8ms, {{.id = 0, .x = 2.0f, .y = 2.0f, .isResampled = false}}}},
+            InputStream{{InputSample{4ms, {{.id = 0, .x = 1.0f, .y = 1.0f, .isResampled = false}}},
+                         InputSample{8ms, {{.id = 0, .x = 2.0f, .y = 2.0f, .isResampled = false}}}},
                         AMOTION_EVENT_ACTION_MOVE,
                         .deviceId = 0};
+
     mResampler->resampleMotionEvent(10ms, motionFromFirstDevice, nullptr);
+
     MotionEvent motionFromSecondDevice =
-            InputStream{{{11ms, {{.id = 0, .x = 1.0f, .y = 1.0f, .isResampled = false}}}},
+            InputStream{{InputSample{11ms,
+                                     {{.id = 0, .x = 3.0f, .y = 3.0f, .isResampled = false}}}},
                         AMOTION_EVENT_ACTION_MOVE,
                         .deviceId = 1};
     const MotionEvent originalMotionEvent = motionFromSecondDevice;
+
     mResampler->resampleMotionEvent(12ms, motionFromSecondDevice, nullptr);
     // The MotionEvent should not be resampled because the second event came from a different device
     // than the previous event.
@@ -308,28 +293,30 @@ TEST_F(ResamplerTest, SinglePointerDifferentDeviceIdBetweenMotionEvents) {
  */
 TEST_F(ResamplerTest, SinglePointerSingleSampleInterpolation) {
     MotionEvent motionEvent =
-            InputStream{{{10ms, {{.id = 0, .x = 1.0f, .y = 1.0f, .isResampled = false}}}},
+            InputStream{{InputSample{10ms,
+                                     {{.id = 0, .x = 1.0f, .y = 2.0f, .isResampled = false}}}},
                         AMOTION_EVENT_ACTION_MOVE};
     const InputMessage futureSample =
-            InputSample{15ms, {{.id = 0, .x = 2.0f, .y = 2.0f, .isResampled = false}}};
+            InputSample{15ms, {{.id = 0, .x = 2.0f, .y = 4.0f, .isResampled = false}}};
 
     const MotionEvent originalMotionEvent = motionEvent;
 
     mResampler->resampleMotionEvent(11ms, motionEvent, &futureSample);
 
     assertMotionEventIsResampledAndCoordsNear(originalMotionEvent, motionEvent,
-                                              Pointer{.id = 0,
-                                                      .x = 1.2f,
-                                                      .y = 1.2f,
-                                                      .isResampled = true});
+                                              {Pointer{.id = 0,
+                                                       .x = 1.2f,
+                                                       .y = 2.4f,
+                                                       .isResampled = true}});
 }
 
 TEST_F(ResamplerTest, SinglePointerDeltaTooSmallInterpolation) {
     MotionEvent motionEvent =
-            InputStream{{{10ms, {{.id = 0, .x = 1.0f, .y = 1.0f, .isResampled = false}}}},
+            InputStream{{InputSample{10ms,
+                                     {{.id = 0, .x = 1.0f, .y = 2.0f, .isResampled = false}}}},
                         AMOTION_EVENT_ACTION_MOVE};
     const InputMessage futureSample =
-            InputSample{11ms, {{.id = 0, .x = 2.0f, .y = 2.0f, .isResampled = false}}};
+            InputSample{11ms, {{.id = 0, .x = 2.0f, .y = 4.0f, .isResampled = false}}};
 
     const MotionEvent originalMotionEvent = motionEvent;
 
@@ -342,25 +329,26 @@ TEST_F(ResamplerTest, SinglePointerDeltaTooSmallInterpolation) {
  * Tests extrapolation given two MotionEvents with a single sample.
  */
 TEST_F(ResamplerTest, SinglePointerSingleSampleExtrapolation) {
-    MotionEvent previousMotionEvent =
-            InputStream{{{5ms, {{.id = 0, .x = 1.0f, .y = 1.0f, .isResampled = false}}}},
+    MotionEvent firstMotionEvent =
+            InputStream{{InputSample{5ms, {{.id = 0, .x = 1.0f, .y = 2.0f, .isResampled = false}}}},
                         AMOTION_EVENT_ACTION_MOVE};
 
-    mResampler->resampleMotionEvent(10ms, previousMotionEvent, nullptr);
+    mResampler->resampleMotionEvent(9ms, firstMotionEvent, nullptr);
 
-    MotionEvent motionEvent =
-            InputStream{{{10ms, {{.id = 0, .x = 1.0f, .y = 1.0f, .isResampled = false}}}},
+    MotionEvent secondMotionEvent =
+            InputStream{{InputSample{10ms,
+                                     {{.id = 0, .x = 2.0f, .y = 4.0f, .isResampled = false}}}},
                         AMOTION_EVENT_ACTION_MOVE};
 
-    const MotionEvent originalMotionEvent = motionEvent;
+    const MotionEvent originalMotionEvent = secondMotionEvent;
 
-    mResampler->resampleMotionEvent(11ms, motionEvent, nullptr);
+    mResampler->resampleMotionEvent(11ms, secondMotionEvent, nullptr);
 
-    assertMotionEventIsResampledAndCoordsNear(originalMotionEvent, motionEvent,
-                                              Pointer{.id = 0,
-                                                      .x = 1.0f,
-                                                      .y = 1.0f,
-                                                      .isResampled = true});
+    assertMotionEventIsResampledAndCoordsNear(originalMotionEvent, secondMotionEvent,
+                                              {Pointer{.id = 0,
+                                                       .x = 2.2f,
+                                                       .y = 4.4f,
+                                                       .isResampled = true}});
     // Integrity of the whole motionEvent
     // History size should increment by 1
     // Check if the resampled value is the last one
@@ -370,27 +358,30 @@ TEST_F(ResamplerTest, SinglePointerSingleSampleExtrapolation) {
 
 TEST_F(ResamplerTest, SinglePointerMultipleSampleInterpolation) {
     MotionEvent motionEvent =
-            InputStream{{{5ms, {{.id = 0, .x = 1.0f, .y = 1.0f, .isResampled = false}}},
-                         {10ms, {{.id = 0, .x = 2.0f, .y = 2.0f, .isResampled = false}}}},
+            InputStream{{InputSample{5ms, {{.id = 0, .x = 1.0f, .y = 2.0f, .isResampled = false}}},
+                         InputSample{10ms,
+                                     {{.id = 0, .x = 2.0f, .y = 3.0f, .isResampled = false}}}},
                         AMOTION_EVENT_ACTION_MOVE};
+
     const InputMessage futureSample =
-            InputSample{15ms, {{.id = 0, .x = 3.0f, .y = 3.0f, .isResampled = false}}};
+            InputSample{15ms, {{.id = 0, .x = 3.0f, .y = 5.0f, .isResampled = false}}};
 
     const MotionEvent originalMotionEvent = motionEvent;
 
     mResampler->resampleMotionEvent(11ms, motionEvent, &futureSample);
 
     assertMotionEventIsResampledAndCoordsNear(originalMotionEvent, motionEvent,
-                                              Pointer{.id = 0,
-                                                      .x = 2.2f,
-                                                      .y = 2.2f,
-                                                      .isResampled = true});
+                                              {Pointer{.id = 0,
+                                                       .x = 2.2f,
+                                                       .y = 3.4f,
+                                                       .isResampled = true}});
 }
 
 TEST_F(ResamplerTest, SinglePointerMultipleSampleExtrapolation) {
     MotionEvent motionEvent =
-            InputStream{{{5ms, {{.id = 0, .x = 1.0f, .y = 1.0f, .isResampled = false}}},
-                         {10ms, {{.id = 0, .x = 2.0f, .y = 2.0f, .isResampled = false}}}},
+            InputStream{{InputSample{5ms, {{.id = 0, .x = 1.0f, .y = 2.0f, .isResampled = false}}},
+                         InputSample{10ms,
+                                     {{.id = 0, .x = 2.0f, .y = 4.0f, .isResampled = false}}}},
                         AMOTION_EVENT_ACTION_MOVE};
 
     const MotionEvent originalMotionEvent = motionEvent;
@@ -398,16 +389,17 @@ TEST_F(ResamplerTest, SinglePointerMultipleSampleExtrapolation) {
     mResampler->resampleMotionEvent(11ms, motionEvent, nullptr);
 
     assertMotionEventIsResampledAndCoordsNear(originalMotionEvent, motionEvent,
-                                              Pointer{.id = 0,
-                                                      .x = 2.2f,
-                                                      .y = 2.2f,
-                                                      .isResampled = true});
+                                              {Pointer{.id = 0,
+                                                       .x = 2.2f,
+                                                       .y = 4.4f,
+                                                       .isResampled = true}});
 }
 
 TEST_F(ResamplerTest, SinglePointerDeltaTooSmallExtrapolation) {
     MotionEvent motionEvent =
-            InputStream{{{9ms, {{.id = 0, .x = 1.0f, .y = 1.0f, .isResampled = false}}},
-                         {10ms, {{.id = 0, .x = 2.0f, .y = 2.0f, .isResampled = false}}}},
+            InputStream{{InputSample{9ms, {{.id = 0, .x = 1.0f, .y = 2.0f, .isResampled = false}}},
+                         InputSample{10ms,
+                                     {{.id = 0, .x = 2.0f, .y = 4.0f, .isResampled = false}}}},
                         AMOTION_EVENT_ACTION_MOVE};
 
     const MotionEvent originalMotionEvent = motionEvent;
@@ -419,8 +411,9 @@ TEST_F(ResamplerTest, SinglePointerDeltaTooSmallExtrapolation) {
 
 TEST_F(ResamplerTest, SinglePointerDeltaTooLargeExtrapolation) {
     MotionEvent motionEvent =
-            InputStream{{{5ms, {{.id = 0, .x = 1.0f, .y = 1.0f, .isResampled = false}}},
-                         {26ms, {{.id = 0, .x = 2.0f, .y = 2.0f, .isResampled = false}}}},
+            InputStream{{InputSample{5ms, {{.id = 0, .x = 1.0f, .y = 2.0f, .isResampled = false}}},
+                         InputSample{26ms,
+                                     {{.id = 0, .x = 2.0f, .y = 4.0f, .isResampled = false}}}},
                         AMOTION_EVENT_ACTION_MOVE};
 
     const MotionEvent originalMotionEvent = motionEvent;
@@ -432,8 +425,9 @@ TEST_F(ResamplerTest, SinglePointerDeltaTooLargeExtrapolation) {
 
 TEST_F(ResamplerTest, SinglePointerResampleTimeTooFarExtrapolation) {
     MotionEvent motionEvent =
-            InputStream{{{5ms, {{.id = 0, .x = 1.0f, .y = 1.0f, .isResampled = false}}},
-                         {25ms, {{.id = 0, .x = 2.0f, .y = 2.0f, .isResampled = false}}}},
+            InputStream{{InputSample{5ms, {{.id = 0, .x = 1.0f, .y = 2.0f, .isResampled = false}}},
+                         InputSample{25ms,
+                                     {{.id = 0, .x = 2.0f, .y = 4.0f, .isResampled = false}}}},
                         AMOTION_EVENT_ACTION_MOVE};
 
     const MotionEvent originalMotionEvent = motionEvent;
@@ -441,9 +435,424 @@ TEST_F(ResamplerTest, SinglePointerResampleTimeTooFarExtrapolation) {
     mResampler->resampleMotionEvent(43ms, motionEvent, nullptr);
 
     assertMotionEventIsResampledAndCoordsNear(originalMotionEvent, motionEvent,
-                                              Pointer{.id = 0,
-                                                      .x = 2.4f,
-                                                      .y = 2.4f,
-                                                      .isResampled = true});
+                                              {Pointer{.id = 0,
+                                                       .x = 2.4f,
+                                                       .y = 4.8f,
+                                                       .isResampled = true}});
+}
+
+TEST_F(ResamplerTest, MultiplePointerSingleSampleInterpolation) {
+    MotionEvent motionEvent =
+            InputStream{{InputSample{5ms,
+                                     {{.id = 0, .x = 1.0f, .y = 1.0f, .isResampled = false},
+                                      {.id = 1, .x = 2.0f, .y = 2.0f, .isResampled = false}}}},
+                        AMOTION_EVENT_ACTION_MOVE};
+
+    const InputMessage futureSample =
+            InputSample{15ms,
+                        {{.id = 0, .x = 3.0f, .y = 3.0f, .isResampled = false},
+                         {.id = 1, .x = 4.0f, .y = 4.0f, .isResampled = false}}};
+
+    const MotionEvent originalMotionEvent = motionEvent;
+
+    mResampler->resampleMotionEvent(11ms, motionEvent, &futureSample);
+
+    assertMotionEventIsResampledAndCoordsNear(originalMotionEvent, motionEvent,
+                                              {Pointer{.x = 2.2f, .y = 2.2f, .isResampled = true},
+                                               Pointer{.x = 3.2f, .y = 3.2f, .isResampled = true}});
+}
+
+TEST_F(ResamplerTest, MultiplePointerSingleSampleExtrapolation) {
+    MotionEvent firstMotionEvent =
+            InputStream{{InputSample{5ms,
+                                     {{.id = 0, .x = 1.0f, .y = 1.0f, .isResampled = false},
+                                      {.id = 1, .x = 2.0f, .y = 2.0f, .isResampled = false}}}},
+                        AMOTION_EVENT_ACTION_MOVE};
+
+    mResampler->resampleMotionEvent(9ms, firstMotionEvent, /*futureSample=*/nullptr);
+
+    MotionEvent secondMotionEvent =
+            InputStream{{InputSample{10ms,
+                                     {{.id = 0, .x = 3.0f, .y = 3.0f, .isResampled = false},
+                                      {.id = 1, .x = 4.0f, .y = 4.0f, .isResampled = false}}}},
+                        AMOTION_EVENT_ACTION_MOVE};
+
+    const MotionEvent originalMotionEvent = secondMotionEvent;
+
+    mResampler->resampleMotionEvent(11ms, secondMotionEvent, /*futureSample=*/nullptr);
+
+    assertMotionEventIsResampledAndCoordsNear(originalMotionEvent, secondMotionEvent,
+                                              {Pointer{.x = 3.4f, .y = 3.4f, .isResampled = true},
+                                               Pointer{.x = 4.4f, .y = 4.4f, .isResampled = true}});
+}
+
+TEST_F(ResamplerTest, MultiplePointerMultipleSampleInterpolation) {
+    MotionEvent motionEvent =
+            InputStream{{InputSample{5ms,
+                                     {{.id = 0, .x = 1.0f, .y = 1.0f, .isResampled = false},
+                                      {.id = 1, .x = 2.0f, .y = 2.0f, .isResampled = false}}},
+                         InputSample{10ms,
+                                     {{.id = 0, .x = 3.0f, .y = 3.0f, .isResampled = false},
+                                      {.id = 1, .x = 4.0f, .y = 4.0f, .isResampled = false}}}},
+                        AMOTION_EVENT_ACTION_MOVE};
+    const InputMessage futureSample =
+            InputSample{15ms,
+                        {{.id = 0, .x = 5.0f, .y = 5.0f, .isResampled = false},
+                         {.id = 1, .x = 6.0f, .y = 6.0f, .isResampled = false}}};
+
+    const MotionEvent originalMotionEvent = motionEvent;
+
+    mResampler->resampleMotionEvent(11ms, motionEvent, &futureSample);
+
+    assertMotionEventIsResampledAndCoordsNear(originalMotionEvent, motionEvent,
+                                              {Pointer{.x = 3.4f, .y = 3.4f, .isResampled = true},
+                                               Pointer{.x = 4.4f, .y = 4.4f, .isResampled = true}});
+}
+
+TEST_F(ResamplerTest, MultiplePointerMultipleSampleExtrapolation) {
+    MotionEvent motionEvent =
+            InputStream{{InputSample{5ms,
+                                     {{.id = 0, .x = 1.0f, .y = 1.0f, .isResampled = false},
+                                      {.id = 1, .x = 2.0f, .y = 2.0f, .isResampled = false}}},
+                         InputSample{10ms,
+                                     {{.id = 0, .x = 3.0f, .y = 3.0f, .isResampled = false},
+                                      {.id = 1, .x = 4.0f, .y = 4.0f, .isResampled = false}}}},
+                        AMOTION_EVENT_ACTION_MOVE};
+
+    const MotionEvent originalMotionEvent = motionEvent;
+
+    mResampler->resampleMotionEvent(11ms, motionEvent, /*futureSample=*/nullptr);
+
+    assertMotionEventIsResampledAndCoordsNear(originalMotionEvent, motionEvent,
+                                              {Pointer{.x = 3.4f, .y = 3.4f, .isResampled = true},
+                                               Pointer{.x = 4.4f, .y = 4.4f, .isResampled = true}});
+}
+
+TEST_F(ResamplerTest, MultiplePointerIncreaseNumPointersInterpolation) {
+    MotionEvent motionEvent =
+            InputStream{{InputSample{10ms,
+                                     {{.id = 0, .x = 1.0f, .y = 1.0f, .isResampled = false},
+                                      {.id = 1, .x = 2.0f, .y = 2.0f, .isResampled = false}}}},
+                        AMOTION_EVENT_ACTION_MOVE};
+
+    const InputMessage futureSample =
+            InputSample{15ms,
+                        {{.id = 0, .x = 3.0f, .y = 3.0f, .isResampled = false},
+                         {.id = 1, .x = 4.0f, .y = 4.0f, .isResampled = false},
+                         {.id = 2, .x = 5.0f, .y = 5.0f, .isResampled = false}}};
+
+    const MotionEvent originalMotionEvent = motionEvent;
+
+    mResampler->resampleMotionEvent(11ms, motionEvent, &futureSample);
+
+    assertMotionEventIsResampledAndCoordsNear(originalMotionEvent, motionEvent,
+                                              {Pointer{.x = 1.4f, .y = 1.4f, .isResampled = true},
+                                               Pointer{.x = 2.4f, .y = 2.4f, .isResampled = true}});
+
+    MotionEvent secondMotionEvent =
+            InputStream{{InputSample{25ms,
+                                     {{.id = 0, .x = 3.0f, .y = 3.0f, .isResampled = false},
+                                      {.id = 1, .x = 4.0f, .y = 4.0f, .isResampled = false},
+                                      {.id = 2, .x = 5.0f, .y = 5.0f, .isResampled = false}}}},
+                        AMOTION_EVENT_ACTION_MOVE};
+
+    const InputMessage secondFutureSample =
+            InputSample{30ms,
+                        {{.id = 0, .x = 5.0f, .y = 5.0f, .isResampled = false},
+                         {.id = 1, .x = 6.0f, .y = 6.0f, .isResampled = false},
+                         {.id = 2, .x = 7.0f, .y = 7.0f, .isResampled = false}}};
+
+    const MotionEvent originalSecondMotionEvent = secondMotionEvent;
+
+    mResampler->resampleMotionEvent(27ms, secondMotionEvent, &secondFutureSample);
+
+    assertMotionEventIsResampledAndCoordsNear(originalSecondMotionEvent, secondMotionEvent,
+                                              {Pointer{.x = 3.8f, .y = 3.8f, .isResampled = true},
+                                               Pointer{.x = 4.8f, .y = 4.8f, .isResampled = true},
+                                               Pointer{.x = 5.8f, .y = 5.8f, .isResampled = true}});
+}
+
+TEST_F(ResamplerTest, MultiplePointerIncreaseNumPointersExtrapolation) {
+    MotionEvent firstMotionEvent =
+            InputStream{{InputSample{5ms,
+                                     {{.id = 0, .x = 1.0f, .y = 1.0f, .isResampled = false},
+                                      {.id = 1, .x = 2.0f, .y = 2.0f, .isResampled = false}}}},
+                        AMOTION_EVENT_ACTION_MOVE};
+
+    mResampler->resampleMotionEvent(9ms, firstMotionEvent, /*futureSample=*/nullptr);
+
+    MotionEvent secondMotionEvent =
+            InputStream{{InputSample{10ms,
+                                     {{.id = 0, .x = 3.0f, .y = 3.0f, .isResampled = false},
+                                      {.id = 1, .x = 4.0f, .y = 4.0f, .isResampled = false},
+                                      {.id = 2, .x = 5.0f, .y = 5.0f, .isResampled = false}}}},
+                        AMOTION_EVENT_ACTION_MOVE};
+
+    const MotionEvent secondOriginalMotionEvent = secondMotionEvent;
+
+    mResampler->resampleMotionEvent(11ms, secondMotionEvent, /*futureSample=*/nullptr);
+
+    assertMotionEventIsNotResampled(secondOriginalMotionEvent, secondMotionEvent);
+}
+
+TEST_F(ResamplerTest, MultiplePointerDecreaseNumPointersInterpolation) {
+    MotionEvent motionEvent =
+            InputStream{{InputSample{10ms,
+                                     {{.id = 0, .x = 3.0f, .y = 3.0f, .isResampled = false},
+                                      {.id = 1, .x = 4.0f, .y = 4.0f, .isResampled = false},
+                                      {.id = 2, .x = 5.0f, .y = 5.0f, .isResampled = false}}}},
+                        AMOTION_EVENT_ACTION_MOVE};
+
+    const InputMessage futureSample =
+            InputSample{15ms,
+                        {{.id = 0, .x = 4.0f, .y = 4.0f, .isResampled = false},
+                         {.id = 1, .x = 5.0f, .y = 5.0f, .isResampled = false}}};
+
+    const MotionEvent originalMotionEvent = motionEvent;
+
+    mResampler->resampleMotionEvent(11ms, motionEvent, &futureSample);
+
+    assertMotionEventIsNotResampled(originalMotionEvent, motionEvent);
+}
+
+TEST_F(ResamplerTest, MultiplePointerDecreaseNumPointersExtrapolation) {
+    MotionEvent firstMotionEvent =
+            InputStream{{InputSample{5ms,
+                                     {{.id = 0, .x = 1.0f, .y = 1.0f, .isResampled = false},
+                                      {.id = 1, .x = 2.0f, .y = 2.0f, .isResampled = false},
+                                      {.id = 2, .x = 3.0f, .y = 3.0f, .isResampled = false}}}},
+                        AMOTION_EVENT_ACTION_MOVE};
+
+    mResampler->resampleMotionEvent(9ms, firstMotionEvent, /*futureSample=*/nullptr);
+
+    MotionEvent secondMotionEvent =
+            InputStream{{InputSample{10ms,
+                                     {{.id = 0, .x = 3.0f, .y = 3.0f, .isResampled = false},
+                                      {.id = 1, .x = 4.0f, .y = 4.0f, .isResampled = false}}}},
+                        AMOTION_EVENT_ACTION_MOVE};
+
+    const MotionEvent secondOriginalMotionEvent = secondMotionEvent;
+
+    mResampler->resampleMotionEvent(11ms, secondMotionEvent, /*futureSample=*/nullptr);
+
+    assertMotionEventIsResampledAndCoordsNear(secondOriginalMotionEvent, secondMotionEvent,
+                                              {Pointer{.x = 3.4f, .y = 3.4f, .isResampled = true},
+                                               Pointer{.x = 4.4f, .y = 4.4f, .isResampled = true}});
+}
+
+TEST_F(ResamplerTest, MultiplePointerDifferentIdOrderInterpolation) {
+    MotionEvent motionEvent =
+            InputStream{{InputSample{10ms,
+                                     {{.id = 0, .x = 1.0f, .y = 1.0f, .isResampled = false},
+                                      {.id = 1, .x = 2.0f, .y = 2.0f, .isResampled = false}}}},
+                        AMOTION_EVENT_ACTION_MOVE};
+
+    const InputMessage futureSample =
+            InputSample{15ms,
+                        {{.id = 1, .x = 4.0f, .y = 4.0f, .isResampled = false},
+                         {.id = 0, .x = 3.0f, .y = 3.0f, .isResampled = false}}};
+
+    const MotionEvent originalMotionEvent = motionEvent;
+
+    mResampler->resampleMotionEvent(11ms, motionEvent, &futureSample);
+
+    assertMotionEventIsNotResampled(originalMotionEvent, motionEvent);
+}
+
+TEST_F(ResamplerTest, MultiplePointerDifferentIdOrderExtrapolation) {
+    MotionEvent firstMotionEvent =
+            InputStream{{InputSample{5ms,
+                                     {{.id = 0, .x = 1.0f, .y = 1.0f, .isResampled = false},
+                                      {.id = 1, .x = 2.0f, .y = 2.0f, .isResampled = false}}}},
+                        AMOTION_EVENT_ACTION_MOVE};
+
+    mResampler->resampleMotionEvent(9ms, firstMotionEvent, /*futureSample=*/nullptr);
+
+    MotionEvent secondMotionEvent =
+            InputStream{{InputSample{10ms,
+                                     {{.id = 1, .x = 4.0f, .y = 4.0f, .isResampled = false},
+                                      {.id = 0, .x = 3.0f, .y = 3.0f, .isResampled = false}}}},
+                        AMOTION_EVENT_ACTION_MOVE};
+
+    const MotionEvent secondOriginalMotionEvent = secondMotionEvent;
+
+    mResampler->resampleMotionEvent(11ms, secondMotionEvent, /*futureSample=*/nullptr);
+
+    assertMotionEventIsNotResampled(secondOriginalMotionEvent, secondMotionEvent);
+}
+
+TEST_F(ResamplerTest, MultiplePointerDifferentIdsInterpolation) {
+    MotionEvent motionEvent =
+            InputStream{{InputSample{10ms,
+                                     {{.id = 0, .x = 1.0f, .y = 1.0f, .isResampled = false},
+                                      {.id = 1, .x = 2.0f, .y = 2.0f, .isResampled = false}}}},
+                        AMOTION_EVENT_ACTION_MOVE};
+
+    const InputMessage futureSample =
+            InputSample{15ms,
+                        {{.id = 1, .x = 4.0f, .y = 4.0f, .isResampled = false},
+                         {.id = 2, .x = 3.0f, .y = 3.0f, .isResampled = false}}};
+
+    const MotionEvent originalMotionEvent = motionEvent;
+
+    mResampler->resampleMotionEvent(11ms, motionEvent, &futureSample);
+
+    assertMotionEventIsNotResampled(originalMotionEvent, motionEvent);
+}
+
+TEST_F(ResamplerTest, MultiplePointerDifferentIdsExtrapolation) {
+    MotionEvent firstMotionEvent =
+            InputStream{{InputSample{5ms,
+                                     {{.id = 0, .x = 1.0f, .y = 1.0f, .isResampled = false},
+                                      {.id = 1, .x = 2.0f, .y = 2.0f, .isResampled = false}}}},
+                        AMOTION_EVENT_ACTION_MOVE};
+
+    mResampler->resampleMotionEvent(9ms, firstMotionEvent, /*futureSample=*/nullptr);
+
+    MotionEvent secondMotionEvent =
+            InputStream{{InputSample{10ms,
+                                     {{.id = 1, .x = 4.0f, .y = 4.0f, .isResampled = false},
+                                      {.id = 2, .x = 3.0f, .y = 3.0f, .isResampled = false}}}},
+                        AMOTION_EVENT_ACTION_MOVE};
+
+    const MotionEvent secondOriginalMotionEvent = secondMotionEvent;
+
+    mResampler->resampleMotionEvent(11ms, secondMotionEvent, /*futureSample=*/nullptr);
+
+    assertMotionEventIsNotResampled(secondOriginalMotionEvent, secondMotionEvent);
+}
+
+TEST_F(ResamplerTest, MultiplePointerDifferentToolTypeInterpolation) {
+    MotionEvent motionEvent = InputStream{{InputSample{10ms,
+                                                       {{.id = 0,
+                                                         .toolType = ToolType::FINGER,
+                                                         .x = 1.0f,
+                                                         .y = 1.0f,
+                                                         .isResampled = false},
+                                                        {.id = 1,
+                                                         .toolType = ToolType::FINGER,
+                                                         .x = 2.0f,
+                                                         .y = 2.0f,
+                                                         .isResampled = false}}}},
+                                          AMOTION_EVENT_ACTION_MOVE};
+
+    const InputMessage futureSample = InputSample{15ms,
+                                                  {{.id = 0,
+                                                    .toolType = ToolType::FINGER,
+                                                    .x = 3.0,
+                                                    .y = 3.0,
+                                                    .isResampled = false},
+                                                   {.id = 1,
+                                                    .toolType = ToolType::STYLUS,
+                                                    .x = 4.0,
+                                                    .y = 4.0,
+                                                    .isResampled = false}}};
+
+    const MotionEvent originalMotionEvent = motionEvent;
+
+    mResampler->resampleMotionEvent(11ms, motionEvent, &futureSample);
+
+    assertMotionEventIsNotResampled(originalMotionEvent, motionEvent);
+}
+
+TEST_F(ResamplerTest, MultiplePointerDifferentToolTypeExtrapolation) {
+    MotionEvent firstMotionEvent = InputStream{{InputSample{5ms,
+                                                            {{.id = 0,
+                                                              .toolType = ToolType::FINGER,
+                                                              .x = 1.0f,
+                                                              .y = 1.0f,
+                                                              .isResampled = false},
+                                                             {.id = 1,
+                                                              .toolType = ToolType::FINGER,
+                                                              .x = 2.0f,
+                                                              .y = 2.0f,
+                                                              .isResampled = false}}}},
+                                               AMOTION_EVENT_ACTION_MOVE};
+
+    mResampler->resampleMotionEvent(9ms, firstMotionEvent, /*futureSample=*/nullptr);
+
+    MotionEvent secondMotionEvent = InputStream{{InputSample{10ms,
+                                                             {{.id = 0,
+                                                               .toolType = ToolType::FINGER,
+                                                               .x = 1.0f,
+                                                               .y = 1.0f,
+                                                               .isResampled = false},
+                                                              {.id = 1,
+                                                               .toolType = ToolType::STYLUS,
+                                                               .x = 2.0f,
+                                                               .y = 2.0f,
+                                                               .isResampled = false}}}},
+                                                AMOTION_EVENT_ACTION_MOVE};
+
+    const MotionEvent secondOriginalMotionEvent = secondMotionEvent;
+
+    mResampler->resampleMotionEvent(11ms, secondMotionEvent, /*futureSample=*/nullptr);
+
+    assertMotionEventIsNotResampled(secondOriginalMotionEvent, secondMotionEvent);
+}
+
+TEST_F(ResamplerTest, MultiplePointerShouldNotResampleToolTypeInterpolation) {
+    MotionEvent motionEvent = InputStream{{InputSample{10ms,
+                                                       {{.id = 0,
+                                                         .toolType = ToolType::PALM,
+                                                         .x = 1.0f,
+                                                         .y = 1.0f,
+                                                         .isResampled = false},
+                                                        {.id = 1,
+                                                         .toolType = ToolType::PALM,
+                                                         .x = 2.0f,
+                                                         .y = 2.0f,
+                                                         .isResampled = false}}}},
+                                          AMOTION_EVENT_ACTION_MOVE};
+
+    const InputMessage futureSample = InputSample{15ms,
+                                                  {{.id = 0,
+                                                    .toolType = ToolType::PALM,
+                                                    .x = 3.0,
+                                                    .y = 3.0,
+                                                    .isResampled = false},
+                                                   {.id = 1,
+                                                    .toolType = ToolType::PALM,
+                                                    .x = 4.0,
+                                                    .y = 4.0,
+                                                    .isResampled = false}}};
+
+    const MotionEvent originalMotionEvent = motionEvent;
+
+    mResampler->resampleMotionEvent(11ms, motionEvent, /*futureSample=*/nullptr);
+
+    assertMotionEventIsNotResampled(originalMotionEvent, motionEvent);
+}
+
+TEST_F(ResamplerTest, MultiplePointerShouldNotResampleToolTypeExtrapolation) {
+    MotionEvent motionEvent = InputStream{{InputSample{5ms,
+                                                       {{.id = 0,
+                                                         .toolType = ToolType::PALM,
+                                                         .x = 1.0f,
+                                                         .y = 1.0f,
+                                                         .isResampled = false},
+                                                        {.id = 1,
+                                                         .toolType = ToolType::PALM,
+                                                         .x = 2.0f,
+                                                         .y = 2.0f,
+                                                         .isResampled = false}}},
+                                           InputSample{10ms,
+                                                       {{.id = 0,
+                                                         .toolType = ToolType::PALM,
+                                                         .x = 3.0f,
+                                                         .y = 3.0f,
+                                                         .isResampled = false},
+                                                        {.id = 1,
+                                                         .toolType = ToolType::PALM,
+                                                         .x = 4.0f,
+                                                         .y = 4.0f,
+                                                         .isResampled = false}}}},
+                                          AMOTION_EVENT_ACTION_MOVE};
+
+    const MotionEvent originalMotionEvent = motionEvent;
+
+    mResampler->resampleMotionEvent(11ms, motionEvent, /*futureSample=*/nullptr);
+
+    assertMotionEventIsNotResampled(originalMotionEvent, motionEvent);
 }
 } // namespace android