Move MotionEvent#split implementation to native
There is already a native implementation of split in InputDispatcher.
Prevent code duplication by moving the Java impl to native. The Java
impl is not correct, because it cannot access all values like the
transforms to initialize the split event with.
Bug: 326171104
Test: atest libinput_tests
Test: atest inputflinger_tests
Change-Id: I6230b6aa0696dcfc275a5a14ab4af3d4b7bd0b45
diff --git a/libs/input/Input.cpp b/libs/input/Input.cpp
index 9e0ce1d..d58fb42 100644
--- a/libs/input/Input.cpp
+++ b/libs/input/Input.cpp
@@ -60,6 +60,45 @@
return !isFromSource(source, AINPUT_SOURCE_CLASS_POINTER);
}
+int32_t resolveActionForSplitMotionEvent(
+ int32_t action, int32_t flags, const std::vector<PointerProperties>& pointerProperties,
+ const std::vector<PointerProperties>& splitPointerProperties) {
+ LOG_ALWAYS_FATAL_IF(splitPointerProperties.empty());
+ const auto maskedAction = MotionEvent::getActionMasked(action);
+ if (maskedAction != AMOTION_EVENT_ACTION_POINTER_DOWN &&
+ maskedAction != AMOTION_EVENT_ACTION_POINTER_UP) {
+ // The action is unaffected by splitting this motion event.
+ return action;
+ }
+ const auto actionIndex = MotionEvent::getActionIndex(action);
+ if (CC_UNLIKELY(actionIndex >= pointerProperties.size())) {
+ LOG(FATAL) << "Action index is out of bounds, index: " << actionIndex;
+ }
+
+ const auto affectedPointerId = pointerProperties[actionIndex].id;
+ std::optional<uint32_t> splitActionIndex;
+ for (uint32_t i = 0; i < splitPointerProperties.size(); i++) {
+ if (affectedPointerId == splitPointerProperties[i].id) {
+ splitActionIndex = i;
+ break;
+ }
+ }
+ if (!splitActionIndex.has_value()) {
+ // The affected pointer is not part of the split motion event.
+ return AMOTION_EVENT_ACTION_MOVE;
+ }
+
+ if (splitPointerProperties.size() > 1) {
+ return maskedAction | (*splitActionIndex << AMOTION_EVENT_ACTION_POINTER_INDEX_SHIFT);
+ }
+
+ if (maskedAction == AMOTION_EVENT_ACTION_POINTER_UP) {
+ return ((flags & AMOTION_EVENT_FLAG_CANCELED) != 0) ? AMOTION_EVENT_ACTION_CANCEL
+ : AMOTION_EVENT_ACTION_UP;
+ }
+ return AMOTION_EVENT_ACTION_DOWN;
+}
+
} // namespace
const char* motionClassificationToString(MotionClassification classification) {
@@ -584,6 +623,28 @@
}
}
+void MotionEvent::splitFrom(const android::MotionEvent& other,
+ std::bitset<MAX_POINTER_ID + 1> splitPointerIds, int32_t newEventId) {
+ // TODO(b/327503168): The down time should be a parameter to the split function, because only
+ // the caller can know when the first event went down on the target.
+ const nsecs_t splitDownTime = other.mDownTime;
+
+ auto [action, pointerProperties, pointerCoords] =
+ split(other.getAction(), other.getFlags(), other.getHistorySize(),
+ other.mPointerProperties, other.mSamplePointerCoords, splitPointerIds);
+
+ // Initialize the event with zero pointers, and manually set the split pointers.
+ initialize(newEventId, other.mDeviceId, other.mSource, other.mDisplayId, /*hmac=*/{}, action,
+ other.mActionButton, other.mFlags, other.mEdgeFlags, other.mMetaState,
+ other.mButtonState, other.mClassification, other.mTransform, other.mXPrecision,
+ other.mYPrecision, other.mRawXCursorPosition, other.mRawYCursorPosition,
+ other.mRawTransform, splitDownTime, other.getEventTime(), /*pointerCount=*/0,
+ pointerProperties.data(), pointerCoords.data());
+ mPointerProperties = std::move(pointerProperties);
+ mSamplePointerCoords = std::move(pointerCoords);
+ mSampleEventTimes = other.mSampleEventTimes;
+}
+
void MotionEvent::addSample(
int64_t eventTime,
const PointerCoords* pointerCoords) {
@@ -934,6 +995,45 @@
return android::base::StringPrintf("%" PRId32, action);
}
+std::tuple<int32_t, std::vector<PointerProperties>, std::vector<PointerCoords>> MotionEvent::split(
+ int32_t action, int32_t flags, int32_t historySize,
+ const std::vector<PointerProperties>& pointerProperties,
+ const std::vector<PointerCoords>& pointerCoords,
+ std::bitset<MAX_POINTER_ID + 1> splitPointerIds) {
+ LOG_ALWAYS_FATAL_IF(!splitPointerIds.any());
+ const auto pointerCount = pointerProperties.size();
+ LOG_ALWAYS_FATAL_IF(pointerCoords.size() != (pointerCount * (historySize + 1)));
+ const auto splitCount = splitPointerIds.count();
+
+ std::vector<PointerProperties> splitPointerProperties;
+ std::vector<PointerCoords> splitPointerCoords;
+
+ for (uint32_t i = 0; i < pointerCount; i++) {
+ if (splitPointerIds.test(pointerProperties[i].id)) {
+ splitPointerProperties.emplace_back(pointerProperties[i]);
+ }
+ }
+ for (uint32_t i = 0; i < pointerCoords.size(); i++) {
+ if (splitPointerIds.test(pointerProperties[i % pointerCount].id)) {
+ splitPointerCoords.emplace_back(pointerCoords[i]);
+ }
+ }
+ LOG_ALWAYS_FATAL_IF(splitPointerCoords.size() !=
+ (splitPointerProperties.size() * (historySize + 1)));
+
+ if (CC_UNLIKELY(splitPointerProperties.size() != splitCount)) {
+ LOG(FATAL) << "Cannot split MotionEvent: Requested splitting " << splitCount
+ << " pointers from the original event, but the original event only contained "
+ << splitPointerProperties.size() << " of those pointers.";
+ }
+
+ // TODO(b/327503168): Verify the splitDownTime here once it is used correctly.
+
+ const auto splitAction = resolveActionForSplitMotionEvent(action, flags, pointerProperties,
+ splitPointerProperties);
+ return {splitAction, splitPointerProperties, splitPointerCoords};
+}
+
// Apply the given transformation to the point without checking whether the entire transform
// should be disregarded altogether for the provided source.
static inline vec2 calculateTransformedXYUnchecked(uint32_t source, const ui::Transform& transform,