1.inputmanager启动源码分析
在SystemServer.java中构造了 inputmanagerservice的对象，在其构造函数中，最重要的是这个nativeInit函数。 下面是核心代码
java
inputManager = new InputManagerService(context);
public InputManagerService(Context context) {
.........
mPtr = nativeInit(this, mContext, mHandler.getLooper().getQueue());
.........
LocalServices.addService(InputManagerInternal.class, new LocalService());
}nativeinit函数
对应的jni函数文件名：com_android_server_input_InputManagerService.cpp
nativeInit 构造了一个NativeInputManager，核心代码中构造了一个EventHub和一个InputManager，并且将EventHub传递给了InputManager。那么InputManager就持有了EventHub类。后续可以看到这个EventHub是读取驱动节点数据的核心类。有用到epoll来监听节点
cpp
EventHub::EventHub(void) :
mEpollFd = epoll_create(EPOLL_SIZE_HINT);
}在InputManager的构造函数中可以看到接收了InputReaderPolicyInterface 和 InputDispatcherPolicyInterface 虚基类的两个子类对象，因为外部传入的两个this，说明NativeInputManager是继承了这两个虚基类的，这里就不放代码了。
cpp
NativeInputManager::NativeInputManager(jobject contextObj,
jobject serviceObj, const sp<Looper>& looper) :
mLooper(looper), mInteractive(true) {
...........
sp<EventHub> eventHub = new EventHub();
mInputManager = new InputManager(eventHub, this, this);
}
InputManager::InputManager(
const sp<EventHubInterface>& eventHub,
const sp<InputReaderPolicyInterface>& readerPolicy,
const sp<InputDispatcherPolicyInterface>& dispatcherPolicy) {
mDispatcher = new InputDispatcher(dispatcherPolicy);
mReader = new InputReader(eventHub, readerPolicy, mDispatcher);
initialize();
}然后去创建了继承了线程的对象
cpp
void InputManager::initialize() {
mReaderThread = new InputReaderThread(mReader);
mDispatcherThread = new InputDispatcherThread(mDispatcher);
}线程的启动是在nativeStart，最后走到InputManager.cpp中的start函数启动线程
cpp
status_t InputManager::start() {
status_t result = mDispatcherThread->run("InputDispatcher", PRIORITY_URGENT_DISPLAY);
if (result) {
ALOGE("Could not start InputDispatcher thread due to error %d.", result);
return result;
}
result = mReaderThread->run("InputReader", PRIORITY_URGENT_DISPLAY);
if (result) {
ALOGE("Could not start InputReader thread due to error %d.", result);
mDispatcherThread->requestExit();
return result;
}
return OK;
}2.inputReader源码
启动后调用到InputReader.cpp的loopOnce，
cpp
void InputReader::loopOnce() {
.........
size_t count = mEventHub->getEvents(timeoutMillis, mEventBuffer, EVENT_BUFFER_SIZE);
.........
}
在InputReader.h中可以看到mEventBuffer的声明和定义，相当于给getEvents传递了一个长度为256 类型为RawEvent的数组
// The event queue.
static const int EVENT_BUFFER_SIZE = 256;
RawEvent mEventBuffer[EVENT_BUFFER_SIZE];
在EventHub.h可以看到RawEvent的声明，结构体中的这些变量和getevent命令看到的数据非常类似。
/*
* A raw event as retrieved from the EventHub.
*/
struct RawEvent {
nsecs_t when;
int32_t deviceId;
int32_t type;
int32_t code;
int32_t value;
};在getEvents 函数中，代码量过大，因此贴核心代码
cpp
size_t EventHub::getEvents(int timeoutMillis, RawEvent* buffer, size_t bufferSize) {
struct input_event readBuffer[bufferSize];//创建了input_event 的数组，结构体中的数据和RawEvent实际上大差不差
RawEvent* event = buffer;//event 指向数组头
size_t capacity = bufferSize;
bool awoken = false;
for (;;) {
if (mNeedToScanDevices) {//默认第一次进来需要扫描设备
mNeedToScanDevices = false;
scanDevicesLocked();
mNeedToSendFinishedDeviceScan = true;
}
.........
//看后面代码继续分析
}scanDevicesLocked函数的详细解释
cpp
static const char *DEVICE_PATH = "/dev/input";
void EventHub::scanDevicesLocked() {
status_t res = scanDirLocked(DEVICE_PATH);
if(res < 0) {
ALOGE("scan dir failed for %s\n", DEVICE_PATH);
}
if (mDevices.indexOfKey(VIRTUAL_KEYBOARD_ID) < 0) {
createVirtualKeyboardLocked();
}
}
//打开文件夹/dev/input，读取文件夹下面所有节点，然后在分别打开对应的文件openDeviceLocked
//有了这些信息之后，可以通过这些信息去创建Device对象， 对对应设备加载配置文件或者配置属性
status_t EventHub::scanDirLocked(const char *dirname)
{
char devname[PATH_MAX];
char *filename;
DIR *dir;
struct dirent *de;
dir = opendir(dirname);
if(dir == NULL)
return -1;
strcpy(devname, dirname);
filename = devname + strlen(devname);
*filename++ = '/';
while((de = readdir(dir))) {
if(de->d_name[0] == '.' &&
(de->d_name[1] == '\0' ||
(de->d_name[1] == '.' && de->d_name[2] == '\0')))
continue;
strcpy(filename, de->d_name);
openDeviceLocked(devname);
}
closedir(dir);
return 0;
}
//这个函数很长，核心就是通过ioctl获取一些device 的信息，
status_t EventHub::openDeviceLocked(const char *devicePath) {
// Get device driver version.
int driverVersion;
if(ioctl(fd, EVIOCGVERSION, &driverVersion)) {
ALOGE("could not get driver version for %s, %s\n", devicePath, strerror(errno));
close(fd);
return -1;
}
// Get device identifier.
struct input_id inputId;
if(ioctl(fd, EVIOCGID, &inputId)) {
ALOGE("could not get device input id for %s, %s\n", devicePath, strerror(errno));
close(fd);
return -1;
}
// Allocate device. (The device object takes ownership of the fd at this point.)
int32_t deviceId = mNextDeviceId++;
Device* device = new Device(fd, deviceId, String8(devicePath), identifier);
// Load the configuration file for the device.
loadConfigurationLocked(device);//加载配置文件
// See if this is a touch pad.//对触摸屏配置属性 判断是不是多指触摸
// Is this a new modern multi-touch driver?
if (test_bit(ABS_MT_POSITION_X, device->absBitmask)
&& test_bit(ABS_MT_POSITION_Y, device->absBitmask)) {
// Some joysticks such as the PS3 controller report axes that conflict
// with the ABS_MT range. Try to confirm that the device really is
// a touch screen.
if (test_bit(BTN_TOUCH, device->keyBitmask) || !haveGamepadButtons) {
device->classes |= INPUT_DEVICE_CLASS_TOUCH | INPUT_DEVICE_CLASS_TOUCH_MT;
}
// Is this an old style single-touch driver?
} else if (test_bit(BTN_TOUCH, device->keyBitmask)
&& test_bit(ABS_X, device->absBitmask)
&& test_bit(ABS_Y, device->absBitmask)) {
device->classes |= INPUT_DEVICE_CLASS_TOUCH;
// Is this a BT stylus?
} else if ((test_bit(ABS_PRESSURE, device->absBitmask) ||
test_bit(BTN_TOUCH, device->keyBitmask))
&& !test_bit(ABS_X, device->absBitmask)
&& !test_bit(ABS_Y, device->absBitmask)) {
device->classes |= INPUT_DEVICE_CLASS_EXTERNAL_STYLUS;
// Keyboard will try to claim some of the buttons but we really want to reserve those so we
// can fuse it with the touch screen data, so just take them back. Note this means an
// external stylus cannot also be a keyboard device.
device->classes &= ~INPUT_DEVICE_CLASS_KEYBOARD;
}
// Load the key map.//加载按键的配置文件
// We need to do this for joysticks too because the key layout may specify axes.
status_t keyMapStatus = NAME_NOT_FOUND;
if (device->classes & (INPUT_DEVICE_CLASS_KEYBOARD | INPUT_DEVICE_CLASS_JOYSTICK)) {
// Load the keymap for the device.
keyMapStatus = loadKeyMapLocked(device);
}
if (registerDeviceForEpollLocked(device) != OK) {
delete device;
return -1;
}
configureFd(device);
addDeviceLocked(device);添加device 将所有扫描到的device通过头插的方式用链表链接起来
}
注册监听fd
status_t EventHub::registerDeviceForEpollLocked(Device* device) {
struct epoll_event eventItem;
memset(&eventItem, 0, sizeof(eventItem));
eventItem.events = EPOLLIN;
if (mUsingEpollWakeup) {
eventItem.events |= EPOLLWAKEUP;
}
eventItem.data.u32 = device->id;
if (epoll_ctl(mEpollFd, EPOLL_CTL_ADD, device->fd, &eventItem)) {
ALOGE("Could not add device fd to epoll instance. errno=%d", errno);
return -errno;
}
return OK;
}
//这一段检查输入设备是否为键盘（INPUT_DEVICE_CLASS_KEYBOARD），然后通过 ioctl 调用 EVIOCSREP //来禁用内核的键盘按键重复功能，因为用户态代码会自己处理按键重复逻辑
void EventHub::configureFd(Device* device) {
// Set fd parameters with ioctl, such as key repeat, suspend block, and clock type
if (device->classes & INPUT_DEVICE_CLASS_KEYBOARD) {
// Disable kernel key repeat since we handle it ourselves
unsigned int repeatRate[] = {0, 0};
if (ioctl(device->fd, EVIOCSREP, repeatRate)) {
ALOGW("Unable to disable kernel key repeat for %s: %s",
device->path.string(), strerror(errno));
}
}
String8 wakeMechanism("EPOLLWAKEUP");
//这里是为设备配置挂起阻止机制。当 mUsingEpollWakeup 未被启用时，它会尝试通过 ioctl 调用 //EVIOCSSUSPENDBLOCK 来阻止设备进入挂起状态。这个机制用于保证当设备处于挂起状态时，仍然能够唤醒//系统处理输入事件
if (!mUsingEpollWakeup) {
#ifndef EVIOCSSUSPENDBLOCK
// uapi headers don't include EVIOCSSUSPENDBLOCK, and future kernels
// will use an epoll flag instead, so as long as we want to support
// this feature, we need to be prepared to define the ioctl ourselves.
#define EVIOCSSUSPENDBLOCK _IOW('E', 0x91, int)
#endif
if (ioctl(device->fd, EVIOCSSUSPENDBLOCK, 1)) {
wakeMechanism = "<none>";
} else {
wakeMechanism = "EVIOCSSUSPENDBLOCK";
}
}
//设置输入设备使用单调时钟（CLOCK_MONOTONIC）来记录事件的时间戳。单调时钟保证时间总是向前移动，//避免系统时钟调整（如夏令时变化）对输入事件的时间戳产生影响
// Tell the kernel that we want to use the monotonic clock for reporting timestamps
// associated with input events. This is important because the input system
// uses the timestamps extensively and assumes they were recorded using the monotonic
// clock.
int clockId = CLOCK_MONOTONIC;
bool usingClockIoctl = !ioctl(device->fd, EVIOCSCLOCKID, &clockId);
ALOGI("wakeMechanism=%s, usingClockIoctl=%s", wakeMechanism.string(),
toString(usingClockIoctl));
}
void EventHub::addDeviceLocked(Device* device) {
mDevices.add(device->id, device);
device->next = mOpeningDevices;
mOpeningDevices = device;
}scanDevicesLocked 总结就是扫描监听文件，通过ioctl去驱动中获取不同设备的信息，不同输入设陪配置流程不同，加载配置文件，创建Device，最后将Device存起来。
cpp
//这段代码就是将刚才形成链表的device分别遍历将id取出来，赋值给event存起来。
while (mOpeningDevices != NULL) {
Device* device = mOpeningDevices;
ALOGV("Reporting device opened: id=%d, name=%s\n",
device->id, device->path.string());
mOpeningDevices = device->next;
event->when = now;
event->deviceId = device->id == mBuiltInKeyboardId ? 0 : device->id;
event->type = DEVICE_ADDED;
event += 1;
mNeedToSendFinishedDeviceScan = true;
if (--capacity == 0) {
break;
}
}
//这里为true，如果有5个device的话，这里在添加一个，那么就总共有6个了。
if (mNeedToSendFinishedDeviceScan) {
mNeedToSendFinishedDeviceScan = false;
event->when = now;
event->type = FINISHED_DEVICE_SCAN;
event += 1;
if (--capacity == 0) {
break;
}
}接下来就会执行这里，因为第一次扫描设备，其它代码都不会执行
cpp
// Return now if we have collected any events or if we were explicitly awoken.
if (event != buffer || awoken) {
break;
}
//break之后，返回扫描到的设备数
// All done, return the number of events we read.
return event - buffer;在InputReader.cpp中，在getEvents函数之后会返回设备数，如果扫描到了5个设备，那么这里会返回6，具体可以看上面getEvents的函数源码解析
cpp
void InputReader::loopOnce() {
int32_t oldGeneration;
int32_t timeoutMillis;
bool inputDevicesChanged = false;
..........
size_t count = mEventHub->getEvents(timeoutMillis, mEventBuffer, EVENT_BUFFER_SIZE);
{ // acquire lock
AutoMutex _l(mLock);
mReaderIsAliveCondition.broadcast();
if (count) {
processEventsLocked(mEventBuffer, count);
}
if (mNextTimeout != LLONG_MAX) {
nsecs_t now = systemTime(SYSTEM_TIME_MONOTONIC);
if (now >= mNextTimeout) {
#if DEBUG_RAW_EVENTS
ALOGD("Timeout expired, latency=%0.3fms", (now - mNextTimeout) * 0.000001f);
#endif
mNextTimeout = LLONG_MAX;
timeoutExpiredLocked(now);
}
}
if (oldGeneration != mGeneration) {
inputDevicesChanged = true;
getInputDevicesLocked(inputDevices);
}
} // release lock
// Send out a message that the describes the changed input devices.
if (inputDevicesChanged) {
mPolicy->notifyInputDevicesChanged(inputDevices);
}
// Flush queued events out to the listener.
// This must happen outside of the lock because the listener could potentially call
// back into the InputReader's methods, such as getScanCodeState, or become blocked
// on another thread similarly waiting to acquire the InputReader lock thereby
// resulting in a deadlock. This situation is actually quite plausible because the
// listener is actually the input dispatcher, which calls into the window manager,
// which occasionally calls into the input reader.
mQueuedListener->flush();
}就下来会进入到processEventsLocked对device进行处理，很明显，根据device type，这里将会进入addDeviceLocked
cpp
void InputReader::processEventsLocked(const RawEvent* rawEvents, size_t count) {
for (const RawEvent* rawEvent = rawEvents; count;) {
int32_t type = rawEvent->type;
size_t batchSize = 1;
if (type < EventHubInterface::FIRST_SYNTHETIC_EVENT) {
int32_t deviceId = rawEvent->deviceId;
while (batchSize < count) {
if (rawEvent[batchSize].type >= EventHubInterface::FIRST_SYNTHETIC_EVENT
|| rawEvent[batchSize].deviceId != deviceId) {
break;
}
batchSize += 1;
}
#if DEBUG_RAW_EVENTS
ALOGD("BatchSize: %zu Count: %zu", batchSize, count);
#endif
processEventsForDeviceLocked(deviceId, rawEvent, batchSize);
} else {
switch (rawEvent->type) {
case EventHubInterface::DEVICE_ADDED:
addDeviceLocked(rawEvent->when, rawEvent->deviceId);
break;
case EventHubInterface::DEVICE_REMOVED:
removeDeviceLocked(rawEvent->when, rawEvent->deviceId);
break;
case EventHubInterface::FINISHED_DEVICE_SCAN:
handleConfigurationChangedLocked(rawEvent->when);
break;
default:
ALOG_ASSERT(false); // can't happen
break;
}
}
count -= batchSize;
rawEvent += batchSize;
}
}
void InputReader::addDeviceLocked(nsecs_t when, int32_t deviceId) {
//这里验证deviceId是否在mDevices中存在，如果存在，就不需要再添加一遍了
ssize_t deviceIndex = mDevices.indexOfKey(deviceId);
if (deviceIndex >= 0) {
ALOGW("Ignoring spurious device added event for deviceId %d.", deviceId);
return;
}
//根据deviceId去获取device的相关信息
InputDeviceIdentifier identifier = mEventHub->getDeviceIdentifier(deviceId);
uint32_t classes = mEventHub->getDeviceClasses(deviceId);
int32_t controllerNumber = mEventHub->getDeviceControllerNumber(deviceId);
//创建InputDevice
InputDevice* device = createDeviceLocked(deviceId, controllerNumber, identifier, classes);
device->configure(when, &mConfig, 0);
device->reset(when);
if (device->isIgnored()) {
ALOGI("Device added: id=%d, name='%s' (ignored non-input device)", deviceId,
identifier.name.string());
} else {
ALOGI("Device added: id=%d, name='%s', sources=0x%08x", deviceId,
identifier.name.string(), device->getSources());
}
//将InputDevice放入到mDevices存起来
mDevices.add(deviceId, device);
bumpGenerationLocked();
if (device->getClasses() & INPUT_DEVICE_CLASS_EXTERNAL_STYLUS) {
notifyExternalStylusPresenceChanged();
}
}
//这里是给每个InputDevice都添加了一个Mapper，由Mapper将原始数据转换为真正的触摸数据
InputDevice* InputReader::createDeviceLocked(int32_t deviceId, int32_t controllerNumber,
const InputDeviceIdentifier& identifier, uint32_t classes) {
InputDevice* device = new InputDevice(&mContext, deviceId, bumpGenerationLocked(),
controllerNumber, identifier, classes);
// External devices.
if (classes & INPUT_DEVICE_CLASS_EXTERNAL) {
device->setExternal(true);
}
// Devices with mics.
if (classes & INPUT_DEVICE_CLASS_MIC) {
device->setMic(true);
}
// Switch-like devices.
if (classes & INPUT_DEVICE_CLASS_SWITCH) {
device->addMapper(new SwitchInputMapper(device));
}
// Scroll wheel-like devices.
if (classes & INPUT_DEVICE_CLASS_ROTARY_ENCODER) {
device->addMapper(new RotaryEncoderInputMapper(device));
}
// Vibrator-like devices.
if (classes & INPUT_DEVICE_CLASS_VIBRATOR) {
device->addMapper(new VibratorInputMapper(device));
}
// Keyboard-like devices.
uint32_t keyboardSource = 0;
int32_t keyboardType = AINPUT_KEYBOARD_TYPE_NON_ALPHABETIC;
if (classes & INPUT_DEVICE_CLASS_KEYBOARD) {
keyboardSource |= AINPUT_SOURCE_KEYBOARD;
}
if (classes & INPUT_DEVICE_CLASS_ALPHAKEY) {
keyboardType = AINPUT_KEYBOARD_TYPE_ALPHABETIC;
}
if (classes & INPUT_DEVICE_CLASS_DPAD) {
keyboardSource |= AINPUT_SOURCE_DPAD;
}
if (classes & INPUT_DEVICE_CLASS_GAMEPAD) {
keyboardSource |= AINPUT_SOURCE_GAMEPAD;
}
if (keyboardSource != 0) {
device->addMapper(new KeyboardInputMapper(device, keyboardSource, keyboardType));
}
// Cursor-like devices.
if (classes & INPUT_DEVICE_CLASS_CURSOR) {
device->addMapper(new CursorInputMapper(device));
}
// Touchscreens and touchpad devices.
if (classes & INPUT_DEVICE_CLASS_TOUCH_MT) {
device->addMapper(new MultiTouchInputMapper(device));
} else if (classes & INPUT_DEVICE_CLASS_TOUCH) {
device->addMapper(new SingleTouchInputMapper(device));
}
// Joystick-like devices.
if (classes & INPUT_DEVICE_CLASS_JOYSTICK) {
device->addMapper(new JoystickInputMapper(device));
}
// External stylus-like devices.
if (classes & INPUT_DEVICE_CLASS_EXTERNAL_STYLUS) {
device->addMapper(new ExternalStylusInputMapper(device));
}
return device;
}在processEventsLocked中，会循环处理每个device。
然后循环第二次进入getevent，前面的流程都不会执行，在这里会等待事件的发生，如果有事件发生，那么mPendingEventItems中将会存储eventItem
cpp
mPendingEventIndex = 0;
release_wake_lock(WAKE_LOCK_ID);
int pollResult = epoll_wait(mEpollFd, mPendingEventItems, EPOLL_MAX_EVENTS, timeoutMillis);如果有事件发生，那么mPendingEventIndex将会为0，mPendingEventCount至少也是1.就会进入这个while循环中。
cpp
while (mPendingEventIndex < mPendingEventCount) {
const struct epoll_event& eventItem = mPendingEventItems[mPendingEventIndex++];
//判断是否有新的节点添加或删除
if (eventItem.data.u32 == EPOLL_ID_INOTIFY) {
if (eventItem.events & EPOLLIN) {
mPendingINotify = true;
} else {
ALOGW("Received unexpected epoll event 0x%08x for INotify.", eventItem.events);
}
continue;
}
........
//获取对应device，通过device来读取event，最多读取256个inputevent
ssize_t deviceIndex = mDevices.indexOfKey(eventItem.data.u32);
if (deviceIndex < 0) {
ALOGW("Received unexpected epoll event 0x%08x for unknown device id %d.",
eventItem.events, eventItem.data.u32);
continue;
}
Device* device = mDevices.valueAt(deviceIndex);
if (eventItem.events & EPOLLIN) {
int32_t readSize = read(device->fd, readBuffer,
sizeof(struct input_event) * capacity);
if (readSize == 0 || (readSize < 0 && errno == ENODEV)) {
..........
} else if (readSize < 0) {
..........
} else if ((readSize % sizeof(struct input_event)) != 0) {
..........
} else {
int32_t deviceId = device->id == mBuiltInKeyboardId ? 0 : device->id;
//计算读取到了多少个input_event
size_t count = size_t(readSize) / sizeof(struct input_event);
for (size_t i = 0; i < count; i++) {
struct input_event& iev = readBuffer[i];
ALOGV("%s got: time=%d.%06d, type=%d, code=%d, value=%d",
device->path.string(),
(int) iev.time.tv_sec, (int) iev.time.tv_usec,
iev.type, iev.code, iev.value);
// Some input devices may have a better concept of the time
// when an input event was actually generated than the kernel
// which simply timestamps all events on entry to evdev.
// This is a custom Android extension of the input protocol
// mainly intended for use with uinput based device drivers.
if (iev.type == EV_MSC) {
if (iev.code == MSC_ANDROID_TIME_SEC) {
device->timestampOverrideSec = iev.value;
continue;
} else if (iev.code == MSC_ANDROID_TIME_USEC) {
device->timestampOverrideUsec = iev.value;
continue;
}
}
if (device->timestampOverrideSec || device->timestampOverrideUsec) {
iev.time.tv_sec = device->timestampOverrideSec;
iev.time.tv_usec = device->timestampOverrideUsec;
if (iev.type == EV_SYN && iev.code == SYN_REPORT) {
device->timestampOverrideSec = 0;
device->timestampOverrideUsec = 0;
}
ALOGV("applied override time %d.%06d",
int(iev.time.tv_sec), int(iev.time.tv_usec));
}
// Use the time specified in the event instead of the current time
// so that downstream code can get more accurate estimates of
// event dispatch latency from the time the event is enqueued onto
// the evdev client buffer.
//
// The event's timestamp fortuitously uses the same monotonic clock
// time base as the rest of Android. The kernel event device driver
// (drivers/input/evdev.c) obtains timestamps using ktime_get_ts().
// The systemTime(SYSTEM_TIME_MONOTONIC) function we use everywhere
// calls clock_gettime(CLOCK_MONOTONIC) which is implemented as a
// system call that also queries ktime_get_ts().
event->when = nsecs_t(iev.time.tv_sec) * 1000000000LL
+ nsecs_t(iev.time.tv_usec) * 1000LL;
ALOGV("event time %" PRId64 ", now %" PRId64, event->when, now);
// Bug 7291243: Add a guard in case the kernel generates timestamps
// that appear to be far into the future because they were generated
// using the wrong clock source.
//
// This can happen because when the input device is initially opened
// it has a default clock source of CLOCK_REALTIME. Any input events
// enqueued right after the device is opened will have timestamps
// generated using CLOCK_REALTIME. We later set the clock source
// to CLOCK_MONOTONIC but it is already too late.
//
// Invalid input event timestamps can result in ANRs, crashes and
// and other issues that are hard to track down. We must not let them
// propagate through the system.
//
// Log a warning so that we notice the problem and recover gracefully.
if (event->when >= now + 10 * 1000000000LL) {
// Double-check. Time may have moved on.
nsecs_t time = systemTime(SYSTEM_TIME_MONOTONIC);
if (event->when > time) {
ALOGW("An input event from %s has a timestamp that appears to "
"have been generated using the wrong clock source "
"(expected CLOCK_MONOTONIC): "
"event time %" PRId64 ", current time %" PRId64
", call time %" PRId64 ". "
"Using current time instead.",
device->path.string(), event->when, time, now);
event->when = time;
} else {
ALOGV("Event time is ok but failed the fast path and required "
"an extra call to systemTime: "
"event time %" PRId64 ", current time %" PRId64
", call time %" PRId64 ".",
event->when, time, now);
}
}
//在将inputevent转化为RawEvent
event->deviceId = deviceId;
event->type = iev.type;
event->code = iev.code;
event->value = iev.value;
event += 1;
capacity -= 1;
}
if (capacity == 0) {
// The result buffer is full. Reset the pending event index
// so we will try to read the device again on the next iteration.
mPendingEventIndex -= 1;
break;
}
}
}
到这里又因为event != buffer退出循环了，后续去处理RawEvent
// Return now if we have collected any events or if we were explicitly awoken.
if (event != buffer || awoken) {
break;
}调用processEventsLocked对数据进行处理，这里本质上是找出同一个设备产生的一些了device进行处理
cpp
void InputReader::processEventsLocked(const RawEvent* rawEvents, size_t count) {
for (const RawEvent* rawEvent = rawEvents; count;) {
int32_t type = rawEvent->type;
size_t batchSize = 1;
//使用这个逻辑对具体时间进行处理
//1.如果某个设备产生了10个数据，预期是把这10个数据同时处理掉，但是如果这10个数据之间
//有其它设备产生的数据，那么就会退出下面这个while循环。先处理同一个设备产生的数据。
if (type < EventHubInterface::FIRST_SYNTHETIC_EVENT) {
int32_t deviceId = rawEvent->deviceId;
while (batchSize < count) {
if (rawEvent[batchSize].type >= EventHubInterface::FIRST_SYNTHETIC_EVENT
|| rawEvent[batchSize].deviceId != deviceId) {
break;
}
batchSize += 1;
}
#if DEBUG_RAW_EVENTS
ALOGD("BatchSize: %zu Count: %zu", batchSize, count);
#endif
//在这里处理由同一个device产生的一连串的数据
processEventsForDeviceLocked(deviceId, rawEvent, batchSize);
} else {
....
....
}
count -= batchSize;
rawEvent += batchSize;
}
}processEventsForDeviceLocked中找出id对应的InputDevice调用process进行处理
cpp
void InputReader::processEventsForDeviceLocked(int32_t deviceId,
const RawEvent* rawEvents, size_t count) {
ssize_t deviceIndex = mDevices.indexOfKey(deviceId);
if (deviceIndex < 0) {
ALOGW("Discarding event for unknown deviceId %d.", deviceId);
return;
}
InputDevice* device = mDevices.valueAt(deviceIndex);
if (device->isIgnored()) {
//ALOGD("Discarding event for ignored deviceId %d.", deviceId);
return;
}
device->process(rawEvents, count);
}在InputDevice::process函数中，默认mDropUntilNextSync为false，所以调用mapper->process进行处理
cpp
void InputDevice::process(const RawEvent* rawEvents, size_t count) {
// Process all of the events in order for each mapper.
// We cannot simply ask each mapper to process them in bulk because mappers may
// have side-effects that must be interleaved. For example, joystick movement events and
// gamepad button presses are handled by different mappers but they should be dispatched
// in the order received.
size_t numMappers = mMappers.size();
for (const RawEvent* rawEvent = rawEvents; count != 0; rawEvent++) {
#if DEBUG_RAW_EVENTS
ALOGD("Input event: device=%d type=0x%04x code=0x%04x value=0x%08x when=%" PRId64,
rawEvent->deviceId, rawEvent->type, rawEvent->code, rawEvent->value,
rawEvent->when);
#endif
if (mDropUntilNextSync) {
if (rawEvent->type == EV_SYN && rawEvent->code == SYN_REPORT) {
mDropUntilNextSync = false;
#if DEBUG_RAW_EVENTS
ALOGD("Recovered from input event buffer overrun.");
#endif
} else {
#if DEBUG_RAW_EVENTS
ALOGD("Dropped input event while waiting for next input sync.");
#endif
}
} else if (rawEvent->type == EV_SYN && rawEvent->code == SYN_DROPPED) {
//是一种异常情况，不具体分析
ALOGI("Detected input event buffer overrun for device %s.", getName().string());
mDropUntilNextSync = true;
reset(rawEvent->when);
} else {
for (size_t i = 0; i < numMappers; i++) {
InputMapper* mapper = mMappers[i];
mapper->process(rawEvent);
}
}
--count;
}
}如果设备是触摸屏，那么会调用MultiTouchInputMapper的process进行处理，对照数据进行分析
cpp
void MultiTouchInputMapper::process(const RawEvent* rawEvent) {
TouchInputMapper::process(rawEvent);
mMultiTouchMotionAccumulator.process(rawEvent);
}
void MultiTouchMotionAccumulator::process(const RawEvent* rawEvent) {
if (rawEvent->type == EV_ABS) {
//最开始数据是ABS类型
bool newSlot = false;
//是不是用的slot协议，一般都是这种协议
if (mUsingSlotsProtocol) {
//code最开始是ABS_MT_SLOT
if (rawEvent->code == ABS_MT_SLOT) {
//将触点id保存
mCurrentSlot = rawEvent->value;
//表示有新的slot
newSlot = true;
}
} else if (mCurrentSlot < 0) {
mCurrentSlot = 0;
}
//mCurrentSlot 到这里不会小于0，触点大于等于16时将会报错不支持。 第一次slot判断到此结束
if (mCurrentSlot < 0 || size_t(mCurrentSlot) >= mSlotCount) {
#if DEBUG_POINTERS
if (newSlot) {
ALOGW("MultiTouch device emitted invalid slot index %d but it "
"should be between 0 and %zd; ignoring this slot.",
mCurrentSlot, mSlotCount - 1);
}
#endif
} else {
//当mCurrentSlot为0时
Slot* slot = &mSlots[mCurrentSlot];
switch (rawEvent->code) {
case ABS_MT_POSITION_X:
slot->mInUse = true;
slot->mAbsMTPositionX = rawEvent->value;
break;
case ABS_MT_POSITION_Y:
slot->mInUse = true;
slot->mAbsMTPositionY = rawEvent->value;
break;
case ABS_MT_TOUCH_MAJOR:
slot->mInUse = true;
slot->mAbsMTTouchMajor = rawEvent->value;
break;
case ABS_MT_TOUCH_MINOR:
slot->mInUse = true;
slot->mAbsMTTouchMinor = rawEvent->value;
slot->mHaveAbsMTTouchMinor = true;
break;
case ABS_MT_WIDTH_MAJOR:
slot->mInUse = true;
slot->mAbsMTWidthMajor = rawEvent->value;
break;
case ABS_MT_WIDTH_MINOR:
slot->mInUse = true;
slot->mAbsMTWidthMinor = rawEvent->value;
slot->mHaveAbsMTWidthMinor = true;
break;
case ABS_MT_ORIENTATION:
slot->mInUse = true;
slot->mAbsMTOrientation = rawEvent->value;
break;
//abs 数据第二次处理，value不为0，表示触点没松开，触点松开时value为1
case ABS_MT_TRACKING_ID:
if (mUsingSlotsProtocol && rawEvent->value < 0) {
// The slot is no longer in use but it retains its previous contents,
// which may be reused for subsequent touches.
slot->mInUse = false;
} else {
slot->mInUse = true;
slot->mAbsMTTrackingId = rawEvent->value;
}
break;
case ABS_MT_PRESSURE:
slot->mInUse = true;
slot->mAbsMTPressure = rawEvent->value;
break;
case ABS_MT_DISTANCE:
slot->mInUse = true;
slot->mAbsMTDistance = rawEvent->value;
break;
case ABS_MT_TOOL_TYPE:
slot->mInUse = true;
slot->mAbsMTToolType = rawEvent->value;
slot->mHaveAbsMTToolType = true;
break;
}
}
} else if (rawEvent->type == EV_SYN && rawEvent->code == SYN_MT_REPORT) {
// MultiTouch Sync: The driver has returned all data for *one* of the pointers.
mCurrentSlot += 1;
} else if (rawEvent->type == EV_MSC && rawEvent->code == MSC_TIMESTAMP) {
mDeviceTimestamp = rawEvent->value;
}
}
void TouchInputMapper::process(const RawEvent* rawEvent) {
mCursorButtonAccumulator.process(rawEvent);
mCursorScrollAccumulator.process(rawEvent);
mTouchButtonAccumulator.process(rawEvent);
//同步尾
if (rawEvent->type == EV_SYN && rawEvent->code == SYN_REPORT) {
sync(rawEvent->when);
}
}
void TouchInputMapper::sync(nsecs_t when) {
const RawState* last = mRawStatesPending.isEmpty() ?
&mCurrentRawState : &mRawStatesPending.top();
// Push a new state.
mRawStatesPending.push();
RawState* next = &mRawStatesPending.editTop();
next->clear();
next->when = when;
// Sync button state.
next->buttonState = mTouchButtonAccumulator.getButtonState()
| mCursorButtonAccumulator.getButtonState();
// Sync scroll
next->rawVScroll = mCursorScrollAccumulator.getRelativeVWheel();
next->rawHScroll = mCursorScrollAccumulator.getRelativeHWheel();
mCursorScrollAccumulator.finishSync();
// Sync touch
syncTouch(when, next);
// Assign pointer ids.
if (!mHavePointerIds) {
assignPointerIds(last, next);
}
#if DEBUG_RAW_EVENTS
ALOGD("syncTouch: pointerCount %d -> %d, touching ids 0x%08x -> 0x%08x, "
"hovering ids 0x%08x -> 0x%08x",
last->rawPointerData.pointerCount,
next->rawPointerData.pointerCount,
last->rawPointerData.touchingIdBits.value,
next->rawPointerData.touchingIdBits.value,
last->rawPointerData.hoveringIdBits.value,
next->rawPointerData.hoveringIdBits.value);
#endif
processRawTouches(false /*timeout*/);
}
void MultiTouchInputMapper::syncTouch(nsecs_t when, RawState* outState) {
//获取slotcount 值为16
size_t inCount = mMultiTouchMotionAccumulator.getSlotCount();
size_t outCount = 0;
BitSet32 newPointerIdBits;
mHavePointerIds = true;
//这里遍历每个slot 判断触点是不是还在，如果触点不在，直接略过
for (size_t inIndex = 0; inIndex < inCount; inIndex++) {
const MultiTouchMotionAccumulator::Slot* inSlot =
mMultiTouchMotionAccumulator.getSlot(inIndex);
if (!inSlot->isInUse()) {
continue;
}
if (outCount >= MAX_POINTERS) {
#if DEBUG_POINTERS
ALOGD("MultiTouch device %s emitted more than maximum of %d pointers; "
"ignoring the rest.",
getDeviceName().string(), MAX_POINTERS);
#endif
break; // too many fingers!
}
//构建一个触点对象，数据来自slot
RawPointerData::Pointer& outPointer = outState->rawPointerData.pointers[outCount];
outPointer.x = inSlot->getX();
outPointer.y = inSlot->getY();
outPointer.pressure = inSlot->getPressure();
outPointer.touchMajor = inSlot->getTouchMajor();
outPointer.touchMinor = inSlot->getTouchMinor();
outPointer.toolMajor = inSlot->getToolMajor();
outPointer.toolMinor = inSlot->getToolMinor();
outPointer.orientation = inSlot->getOrientation();
outPointer.distance = inSlot->getDistance();
outPointer.tiltX = 0;
outPointer.tiltY = 0;
outPointer.toolType = inSlot->getToolType();
if (outPointer.toolType == AMOTION_EVENT_TOOL_TYPE_UNKNOWN) {
outPointer.toolType = mTouchButtonAccumulator.getToolType();
if (outPointer.toolType == AMOTION_EVENT_TOOL_TYPE_UNKNOWN) {
outPointer.toolType = AMOTION_EVENT_TOOL_TYPE_FINGER;
}
}
bool isHovering = mTouchButtonAccumulator.getToolType() != AMOTION_EVENT_TOOL_TYPE_MOUSE
&& (mTouchButtonAccumulator.isHovering()
|| (mRawPointerAxes.pressure.valid && inSlot->getPressure() <= 0));
outPointer.isHovering = isHovering;
// Assign pointer id using tracking id if available.
if (mHavePointerIds) {
int32_t trackingId = inSlot->getTrackingId();
int32_t id = -1;
if (trackingId >= 0) {
for (BitSet32 idBits(mPointerIdBits); !idBits.isEmpty(); ) {
//查找并清除第一个被标记的位（即值为 1 的位），然后返回该位的索引
uint32_t n = idBits.clearFirstMarkedBit();
if (mPointerTrackingIdMap[n] == trackingId) {
id = n;
}
}
//第一次在这里id小于0，并且mPointerIdBits没有满
if (id < 0 && !mPointerIdBits.isFull()) {
id = mPointerIdBits.markFirstUnmarkedBit();//第一次这里返回0，标记第一个没有被标记过的下标，并返回索引
//保存trackingId
mPointerTrackingIdMap[id] = trackingId;
}
}
if (id < 0) {
mHavePointerIds = false;
outState->rawPointerData.clearIdBits();
newPointerIdBits.clear();
} else {
//记录id
outPointer.id = id;
//第一个触点
outState->rawPointerData.idToIndex[id] = outCount;
outState->rawPointerData.markIdBit(id, isHovering);
newPointerIdBits.markBit(id);
}
}
outCount += 1;
}
outState->deviceTimestamp = mMultiTouchMotionAccumulator.getDeviceTimestamp();
outState->rawPointerData.pointerCount = outCount;
mPointerIdBits = newPointerIdBits;
mMultiTouchMotionAccumulator.finishSync();
}
void TouchInputMapper::processRawTouches(bool timeout) {
//这里判断是不是某个状态抛弃所有触摸数据
if (mDeviceMode == DEVICE_MODE_DISABLED) {
// Drop all input if the device is disabled.
mCurrentRawState.clear();
mRawStatesPending.clear();
return;
}
// Drain any pending touch states. The invariant here is that the mCurrentRawState is always
// valid and must go through the full cook and dispatch cycle. This ensures that anything
// touching the current state will only observe the events that have been dispatched to the
// rest of the pipeline.
const size_t N = mRawStatesPending.size();
size_t count;
for(count = 0; count < N; count++) {
//取出RawState对象的数据，数据在syncTouch时填入
const RawState& next = mRawStatesPending[count];
// A failure to assign the stylus id means that we're waiting on stylus data
// and so should defer the rest of the pipeline.
if (assignExternalStylusId(next, timeout)) {
break;
}
// All ready to go.
clearStylusDataPendingFlags();
//拷贝一份数据
mCurrentRawState.copyFrom(next);
if (mCurrentRawState.when < mLastRawState.when) {
mCurrentRawState.when = mLastRawState.when;
}
//关键方法
cookAndDispatch(mCurrentRawState.when);
}
if (count != 0) {
mRawStatesPending.removeItemsAt(0, count);
}
if (mExternalStylusDataPending) {
if (timeout) {
nsecs_t when = mExternalStylusFusionTimeout - STYLUS_DATA_LATENCY;
clearStylusDataPendingFlags();
mCurrentRawState.copyFrom(mLastRawState);
#if DEBUG_STYLUS_FUSION
ALOGD("Timeout expired, synthesizing event with new stylus data");
#endif
cookAndDispatch(when);
} else if (mExternalStylusFusionTimeout == LLONG_MAX) {
mExternalStylusFusionTimeout = mExternalStylusState.when + TOUCH_DATA_TIMEOUT;
getContext()->requestTimeoutAtTime(mExternalStylusFusionTimeout);
}
}
}分析cookAndDispatch
cpp
void TouchInputMapper::cookAndDispatch(nsecs_t when) {
// Always start with a clean state.
//初始化变量
mCurrentCookedState.clear();
// Apply stylus buttons to current raw state.
applyExternalStylusButtonState(when);
// Handle policy on initial down or hover events.
bool initialDown = mLastRawState.rawPointerData.pointerCount == 0
&& mCurrentRawState.rawPointerData.pointerCount != 0;
uint32_t policyFlags = 0;
bool buttonsPressed = mCurrentRawState.buttonState & ~mLastRawState.buttonState;
if (initialDown || buttonsPressed) {
// If this is a touch screen, hide the pointer on an initial down.
if (mDeviceMode == DEVICE_MODE_DIRECT) {
getContext()->fadePointer();
}
if (mParameters.wake) {
policyFlags |= POLICY_FLAG_WAKE;
}
}
// Consume raw off-screen touches before cooking pointer data.
// If touches are consumed, subsequent code will not receive any pointer data.
if (consumeRawTouches(when, policyFlags)) {
//
mCurrentRawState.rawPointerData.clear();
}
// Cook pointer data. This call populates the mCurrentCookedState.cookedPointerData structure
// with cooked pointer data that has the same ids and indices as the raw data.
// The following code can use either the raw or cooked data, as needed.
//关键方法
cookPointerData();
// Apply stylus pressure to current cooked state.
applyExternalStylusTouchState(when);
// Synthesize key down from raw buttons if needed.
synthesizeButtonKeys(getContext(), AKEY_EVENT_ACTION_DOWN, when, getDeviceId(), mSource,
policyFlags, mLastCookedState.buttonState, mCurrentCookedState.buttonState);
// Dispatch the touches either directly or by translation through a pointer on screen.
if (mDeviceMode == DEVICE_MODE_POINTER) {
for (BitSet32 idBits(mCurrentRawState.rawPointerData.touchingIdBits);
!idBits.isEmpty(); ) {
uint32_t id = idBits.clearFirstMarkedBit();
const RawPointerData::Pointer& pointer =
mCurrentRawState.rawPointerData.pointerForId(id);
if (pointer.toolType == AMOTION_EVENT_TOOL_TYPE_STYLUS
|| pointer.toolType == AMOTION_EVENT_TOOL_TYPE_ERASER) {
mCurrentCookedState.stylusIdBits.markBit(id);
} else if (pointer.toolType == AMOTION_EVENT_TOOL_TYPE_FINGER
|| pointer.toolType == AMOTION_EVENT_TOOL_TYPE_UNKNOWN) {
mCurrentCookedState.fingerIdBits.markBit(id);
} else if (pointer.toolType == AMOTION_EVENT_TOOL_TYPE_MOUSE) {
mCurrentCookedState.mouseIdBits.markBit(id);
}
}
for (BitSet32 idBits(mCurrentRawState.rawPointerData.hoveringIdBits);
!idBits.isEmpty(); ) {
uint32_t id = idBits.clearFirstMarkedBit();
const RawPointerData::Pointer& pointer =
mCurrentRawState.rawPointerData.pointerForId(id);
if (pointer.toolType == AMOTION_EVENT_TOOL_TYPE_STYLUS
|| pointer.toolType == AMOTION_EVENT_TOOL_TYPE_ERASER) {
mCurrentCookedState.stylusIdBits.markBit(id);
}
}
// Stylus takes precedence over all tools, then mouse, then finger.
PointerUsage pointerUsage = mPointerUsage;
if (!mCurrentCookedState.stylusIdBits.isEmpty()) {
mCurrentCookedState.mouseIdBits.clear();
mCurrentCookedState.fingerIdBits.clear();
pointerUsage = POINTER_USAGE_STYLUS;
} else if (!mCurrentCookedState.mouseIdBits.isEmpty()) {
mCurrentCookedState.fingerIdBits.clear();
pointerUsage = POINTER_USAGE_MOUSE;
} else if (!mCurrentCookedState.fingerIdBits.isEmpty() ||
isPointerDown(mCurrentRawState.buttonState)) {
pointerUsage = POINTER_USAGE_GESTURES;
}
dispatchPointerUsage(when, policyFlags, pointerUsage);
} else {
if (mDeviceMode == DEVICE_MODE_DIRECT
&& mConfig.showTouches && mPointerController != NULL) {
mPointerController->setPresentation(PointerControllerInterface::PRESENTATION_SPOT);
mPointerController->fade(PointerControllerInterface::TRANSITION_GRADUAL);
mPointerController->setButtonState(mCurrentRawState.buttonState);
mPointerController->setSpots(mCurrentCookedState.cookedPointerData.pointerCoords,
mCurrentCookedState.cookedPointerData.idToIndex,
mCurrentCookedState.cookedPointerData.touchingIdBits);
}
if (!mCurrentMotionAborted) {
dispatchButtonRelease(when, policyFlags);
dispatchHoverExit(when, policyFlags);
//触摸点派发
dispatchTouches(when, policyFlags);
dispatchHoverEnterAndMove(when, policyFlags);
dispatchButtonPress(when, policyFlags);
}
if (mCurrentCookedState.cookedPointerData.pointerCount == 0) {
mCurrentMotionAborted = false;
}
}
// Synthesize key up from raw buttons if needed.
synthesizeButtonKeys(getContext(), AKEY_EVENT_ACTION_UP, when, getDeviceId(), mSource,
policyFlags, mLastCookedState.buttonState, mCurrentCookedState.buttonState);
// Clear some transient state.
mCurrentRawState.rawVScroll = 0;
mCurrentRawState.rawHScroll = 0;
// Copy current touch to last touch in preparation for the next cycle.
mLastRawState.copyFrom(mCurrentRawState);
mLastCookedState.copyFrom(mCurrentCookedState);
}
void TouchInputMapper::cookPointerData() {
//获取有多少个触点
uint32_t currentPointerCount = mCurrentRawState.rawPointerData.pointerCount;
mCurrentCookedState.cookedPointerData.clear();
mCurrentCookedState.deviceTimestamp =
mCurrentRawState.deviceTimestamp;
//按下点的个数
mCurrentCookedState.cookedPointerData.pointerCount = currentPointerCount;
mCurrentCookedState.cookedPointerData.hoveringIdBits =
mCurrentRawState.rawPointerData.hoveringIdBits;
//按下id的集合
mCurrentCookedState.cookedPointerData.touchingIdBits =
mCurrentRawState.rawPointerData.touchingIdBits;
//判断按下点的个数是否为0，正常不会为0
if (mCurrentCookedState.cookedPointerData.pointerCount == 0) {
mCurrentCookedState.buttonState = 0;
} else {
mCurrentCookedState.buttonState = mCurrentRawState.buttonState;
}
// Walk through the the active pointers and map device coordinates onto
// surface coordinates and adjust for display orientation.
//遍历触点
for (uint32_t i = 0; i < currentPointerCount; i++) {
//取出触点数据
const RawPointerData::Pointer& in = mCurrentRawState.rawPointerData.pointers[i];
// Size
float touchMajor, touchMinor, toolMajor, toolMinor, size;
//size的校准 长轴短轴的校准
switch (mCalibration.sizeCalibration) {
case Calibration::SIZE_CALIBRATION_GEOMETRIC:
case Calibration::SIZE_CALIBRATION_DIAMETER:
case Calibration::SIZE_CALIBRATION_BOX:
case Calibration::SIZE_CALIBRATION_AREA:
if (mRawPointerAxes.touchMajor.valid && mRawPointerAxes.toolMajor.valid) {
touchMajor = in.touchMajor;
touchMinor = mRawPointerAxes.touchMinor.valid ? in.touchMinor : in.touchMajor;
toolMajor = in.toolMajor;
toolMinor = mRawPointerAxes.toolMinor.valid ? in.toolMinor : in.toolMajor;
size = mRawPointerAxes.touchMinor.valid
? avg(in.touchMajor, in.touchMinor) : in.touchMajor;
} else if (mRawPointerAxes.touchMajor.valid) {
toolMajor = touchMajor = in.touchMajor;
toolMinor = touchMinor = mRawPointerAxes.touchMinor.valid
? in.touchMinor : in.touchMajor;
size = mRawPointerAxes.touchMinor.valid
? avg(in.touchMajor, in.touchMinor) : in.touchMajor;
} else if (mRawPointerAxes.toolMajor.valid) {
touchMajor = toolMajor = in.toolMajor;
touchMinor = toolMinor = mRawPointerAxes.toolMinor.valid
? in.toolMinor : in.toolMajor;
size = mRawPointerAxes.toolMinor.valid
? avg(in.toolMajor, in.toolMinor) : in.toolMajor;
} else {
ALOG_ASSERT(false, "No touch or tool axes. "
"Size calibration should have been resolved to NONE.");
touchMajor = 0;
touchMinor = 0;
toolMajor = 0;
toolMinor = 0;
size = 0;
}
if (mCalibration.haveSizeIsSummed && mCalibration.sizeIsSummed) {
uint32_t touchingCount =
mCurrentRawState.rawPointerData.touchingIdBits.count();
if (touchingCount > 1) {
touchMajor /= touchingCount;
touchMinor /= touchingCount;
toolMajor /= touchingCount;
toolMinor /= touchingCount;
size /= touchingCount;
}
}
if (mCalibration.sizeCalibration == Calibration::SIZE_CALIBRATION_GEOMETRIC) {
touchMajor *= mGeometricScale;
touchMinor *= mGeometricScale;
toolMajor *= mGeometricScale;
toolMinor *= mGeometricScale;
} else if (mCalibration.sizeCalibration == Calibration::SIZE_CALIBRATION_AREA) {
touchMajor = touchMajor > 0 ? sqrtf(touchMajor) : 0;
touchMinor = touchMajor;
toolMajor = toolMajor > 0 ? sqrtf(toolMajor) : 0;
toolMinor = toolMajor;
} else if (mCalibration.sizeCalibration == Calibration::SIZE_CALIBRATION_DIAMETER) {
touchMinor = touchMajor;
toolMinor = toolMajor;
}
mCalibration.applySizeScaleAndBias(&touchMajor);
mCalibration.applySizeScaleAndBias(&touchMinor);
mCalibration.applySizeScaleAndBias(&toolMajor);
mCalibration.applySizeScaleAndBias(&toolMinor);
size *= mSizeScale;
break;
default:
touchMajor = 0;
touchMinor = 0;
toolMajor = 0;
toolMinor = 0;
size = 0;
break;
}
// Pressure
float pressure;
switch (mCalibration.pressureCalibration) {
case Calibration::PRESSURE_CALIBRATION_PHYSICAL:
case Calibration::PRESSURE_CALIBRATION_AMPLITUDE:
pressure = in.pressure * mPressureScale;
break;
default:
pressure = in.isHovering ? 0 : 1;
break;
}
//方向校准
// Tilt and Orientation
float tilt;
float orientation;
if (mHaveTilt) {
float tiltXAngle = (in.tiltX - mTiltXCenter) * mTiltXScale;
float tiltYAngle = (in.tiltY - mTiltYCenter) * mTiltYScale;
orientation = atan2f(-sinf(tiltXAngle), sinf(tiltYAngle));
tilt = acosf(cosf(tiltXAngle) * cosf(tiltYAngle));
} else {
tilt = 0;
switch (mCalibration.orientationCalibration) {
case Calibration::ORIENTATION_CALIBRATION_INTERPOLATED:
orientation = in.orientation * mOrientationScale;
break;
case Calibration::ORIENTATION_CALIBRATION_VECTOR: {
int32_t c1 = signExtendNybble((in.orientation & 0xf0) >> 4);
int32_t c2 = signExtendNybble(in.orientation & 0x0f);
if (c1 != 0 || c2 != 0) {
orientation = atan2f(c1, c2) * 0.5f;
float confidence = hypotf(c1, c2);
float scale = 1.0f + confidence / 16.0f;
touchMajor *= scale;
touchMinor /= scale;
toolMajor *= scale;
toolMinor /= scale;
} else {
orientation = 0;
}
break;
}
default:
orientation = 0;
}
}
// Distance 距离校准
float distance;
switch (mCalibration.distanceCalibration) {
case Calibration::DISTANCE_CALIBRATION_SCALED:
distance = in.distance * mDistanceScale;
break;
default:
distance = 0;
}
// Coverage 覆盖面校准
int32_t rawLeft, rawTop, rawRight, rawBottom;
switch (mCalibration.coverageCalibration) {
case Calibration::COVERAGE_CALIBRATION_BOX:
rawLeft = (in.toolMinor & 0xffff0000) >> 16;
rawRight = in.toolMinor & 0x0000ffff;
rawBottom = in.toolMajor & 0x0000ffff;
rawTop = (in.toolMajor & 0xffff0000) >> 16;
break;
default:
rawLeft = rawTop = rawRight = rawBottom = 0;
break;
}
//x y 坐标校准
// Adjust X,Y coords for device calibration
// TODO: Adjust coverage coords?
float xTransformed = in.x, yTransformed = in.y;
mAffineTransform.applyTo(xTransformed, yTransformed);
// Adjust X, Y, and coverage coords for surface orientation.
float x, y;
float left, top, right, bottom;
switch (mSurfaceOrientation) {
case DISPLAY_ORIENTATION_90:
x = float(yTransformed - mRawPointerAxes.y.minValue) * mYScale + mYTranslate;
y = float(mRawPointerAxes.x.maxValue - xTransformed) * mXScale + mXTranslate;
left = float(rawTop - mRawPointerAxes.y.minValue) * mYScale + mYTranslate;
right = float(rawBottom- mRawPointerAxes.y.minValue) * mYScale + mYTranslate;
bottom = float(mRawPointerAxes.x.maxValue - rawLeft) * mXScale + mXTranslate;
top = float(mRawPointerAxes.x.maxValue - rawRight) * mXScale + mXTranslate;
orientation -= M_PI_2;
if (mOrientedRanges.haveOrientation && orientation < mOrientedRanges.orientation.min) {
orientation += (mOrientedRanges.orientation.max - mOrientedRanges.orientation.min);
}
break;
case DISPLAY_ORIENTATION_180:
x = float(mRawPointerAxes.x.maxValue - xTransformed) * mXScale + mXTranslate;
y = float(mRawPointerAxes.y.maxValue - yTransformed) * mYScale + mYTranslate;
left = float(mRawPointerAxes.x.maxValue - rawRight) * mXScale + mXTranslate;
right = float(mRawPointerAxes.x.maxValue - rawLeft) * mXScale + mXTranslate;
bottom = float(mRawPointerAxes.y.maxValue - rawTop) * mYScale + mYTranslate;
top = float(mRawPointerAxes.y.maxValue - rawBottom) * mYScale + mYTranslate;
orientation -= M_PI;
if (mOrientedRanges.haveOrientation && orientation < mOrientedRanges.orientation.min) {
orientation += (mOrientedRanges.orientation.max - mOrientedRanges.orientation.min);
}
break;
case DISPLAY_ORIENTATION_270:
x = float(mRawPointerAxes.y.maxValue - yTransformed) * mYScale + mYTranslate;
y = float(xTransformed - mRawPointerAxes.x.minValue) * mXScale + mXTranslate;
left = float(mRawPointerAxes.y.maxValue - rawBottom) * mYScale + mYTranslate;
right = float(mRawPointerAxes.y.maxValue - rawTop) * mYScale + mYTranslate;
bottom = float(rawRight - mRawPointerAxes.x.minValue) * mXScale + mXTranslate;
top = float(rawLeft - mRawPointerAxes.x.minValue) * mXScale + mXTranslate;
orientation += M_PI_2;
if (mOrientedRanges.haveOrientation && orientation > mOrientedRanges.orientation.max) {
orientation -= (mOrientedRanges.orientation.max - mOrientedRanges.orientation.min);
}
break;
default:
x = float(xTransformed - mRawPointerAxes.x.minValue) * mXScale + mXTranslate;
y = float(yTransformed - mRawPointerAxes.y.minValue) * mYScale + mYTranslate;
left = float(rawLeft - mRawPointerAxes.x.minValue) * mXScale + mXTranslate;
right = float(rawRight - mRawPointerAxes.x.minValue) * mXScale + mXTranslate;
bottom = float(rawBottom - mRawPointerAxes.y.minValue) * mYScale + mYTranslate;
top = float(rawTop - mRawPointerAxes.y.minValue) * mYScale + mYTranslate;
break;
}
// Write output coords.
PointerCoords& out = mCurrentCookedState.cookedPointerData.pointerCoords[i];
out.clear();
out.setAxisValue(AMOTION_EVENT_AXIS_X, x);
out.setAxisValue(AMOTION_EVENT_AXIS_Y, y);
out.setAxisValue(AMOTION_EVENT_AXIS_PRESSURE, pressure);
out.setAxisValue(AMOTION_EVENT_AXIS_SIZE, size);
out.setAxisValue(AMOTION_EVENT_AXIS_TOUCH_MAJOR, touchMajor);
out.setAxisValue(AMOTION_EVENT_AXIS_TOUCH_MINOR, touchMinor);
out.setAxisValue(AMOTION_EVENT_AXIS_ORIENTATION, orientation);
out.setAxisValue(AMOTION_EVENT_AXIS_TILT, tilt);
out.setAxisValue(AMOTION_EVENT_AXIS_DISTANCE, distance);
if (mCalibration.coverageCalibration == Calibration::COVERAGE_CALIBRATION_BOX) {
out.setAxisValue(AMOTION_EVENT_AXIS_GENERIC_1, left);
out.setAxisValue(AMOTION_EVENT_AXIS_GENERIC_2, top);
out.setAxisValue(AMOTION_EVENT_AXIS_GENERIC_3, right);
out.setAxisValue(AMOTION_EVENT_AXIS_GENERIC_4, bottom);
} else {
out.setAxisValue(AMOTION_EVENT_AXIS_TOOL_MAJOR, toolMajor);
out.setAxisValue(AMOTION_EVENT_AXIS_TOOL_MINOR, toolMinor);
}
// Write output properties.
PointerProperties& properties =
mCurrentCookedState.cookedPointerData.pointerProperties[i];
uint32_t id = in.id;
properties.clear();
properties.id = id;
properties.toolType = in.toolType;
// Write id index.
mCurrentCookedState.cookedPointerData.idToIndex[id] = i;
}
}
void TouchInputMapper::dispatchTouches(nsecs_t when, uint32_t policyFlags) {
//触点的个数
BitSet32 currentIdBits = mCurrentCookedState.cookedPointerData.touchingIdBits;
//上一次触点
BitSet32 lastIdBits = mLastCookedState.cookedPointerData.touchingIdBits;
int32_t metaState = getContext()->getGlobalMetaState();
int32_t buttonState = mCurrentCookedState.buttonState;
//本次触点和上一次触点是相等的 没有手指的变化
if (currentIdBits == lastIdBits) {
if (!currentIdBits.isEmpty()) { // 当前这次不为空
// No pointer id changes so this is a move event.
// The listener takes care of batching moves so we don't have to deal with that here.
//没有触点的变化并且不为null,还有事件的变化，所以判定为触点的移动
dispatchMotion(when, policyFlags, mSource,
AMOTION_EVENT_ACTION_MOVE, 0, 0, metaState, buttonState,
AMOTION_EVENT_EDGE_FLAG_NONE,
mCurrentCookedState.deviceTimestamp,
mCurrentCookedState.cookedPointerData.pointerProperties,
mCurrentCookedState.cookedPointerData.pointerCoords,
mCurrentCookedState.cookedPointerData.idToIndex,
currentIdBits, -1,
mOrientedXPrecision, mOrientedYPrecision, mDownTime);
}
} else {
// There may be pointers going up and pointers going down and pointers moving
// all at the same time.
//如果有触点的变化，那么判定是否有触点的按下或抬起或者同时有触点的移动
BitSet32 upIdBits(lastIdBits.value & ~currentIdBits.value);
BitSet32 downIdBits(currentIdBits.value & ~lastIdBits.value);
BitSet32 moveIdBits(lastIdBits.value & currentIdBits.value);
BitSet32 dispatchedIdBits(lastIdBits.value);
// Update last coordinates of pointers that have moved so that we observe the new
// pointer positions at the same time as other pointers that have just gone up.
//比较last触点坐标的变化来判定是否有触点的移动
bool moveNeeded = updateMovedPointers(
mCurrentCookedState.cookedPointerData.pointerProperties,
mCurrentCookedState.cookedPointerData.pointerCoords,
mCurrentCookedState.cookedPointerData.idToIndex,
mLastCookedState.cookedPointerData.pointerProperties,
mLastCookedState.cookedPointerData.pointerCoords,
mLastCookedState.cookedPointerData.idToIndex,
moveIdBits);
if (buttonState != mLastCookedState.buttonState) {
moveNeeded = true;
}
//是否有up事件
// Dispatch pointer up events.
while (!upIdBits.isEmpty()) {
uint32_t upId = upIdBits.clearFirstMarkedBit();
dispatchMotion(when, policyFlags, mSource,
AMOTION_EVENT_ACTION_POINTER_UP, 0, 0, metaState, buttonState, 0,
mCurrentCookedState.deviceTimestamp,
mLastCookedState.cookedPointerData.pointerProperties,
mLastCookedState.cookedPointerData.pointerCoords,
mLastCookedState.cookedPointerData.idToIndex,
dispatchedIdBits, upId, mOrientedXPrecision, mOrientedYPrecision, mDownTime);
dispatchedIdBits.clearBit(upId);
}
// Dispatch move events if any of the remaining pointers moved from their old locations.
// Although applications receive new locations as part of individual pointer up
// events, they do not generally handle them except when presented in a move event.
//是否有move事件
if (moveNeeded && !moveIdBits.isEmpty()) {
ALOG_ASSERT(moveIdBits.value == dispatchedIdBits.value);
dispatchMotion(when, policyFlags, mSource,
AMOTION_EVENT_ACTION_MOVE, 0, 0, metaState, buttonState, 0,
mCurrentCookedState.deviceTimestamp,
mCurrentCookedState.cookedPointerData.pointerProperties,
mCurrentCookedState.cookedPointerData.pointerCoords,
mCurrentCookedState.cookedPointerData.idToIndex,
dispatchedIdBits, -1, mOrientedXPrecision, mOrientedYPrecision, mDownTime);
}
// Dispatch pointer down events using the new pointer locations.
//是否有按下事件
while (!downIdBits.isEmpty()) {
uint32_t downId = downIdBits.clearFirstMarkedBit();
dispatchedIdBits.markBit(downId);
if (dispatchedIdBits.count() == 1) {
// First pointer is going down. Set down time.
mDownTime = when;
}
dispatchMotion(when, policyFlags, mSource,
AMOTION_EVENT_ACTION_POINTER_DOWN, 0, 0, metaState, buttonState, 0,
mCurrentCookedState.deviceTimestamp,
mCurrentCookedState.cookedPointerData.pointerProperties,
mCurrentCookedState.cookedPointerData.pointerCoords,
mCurrentCookedState.cookedPointerData.idToIndex,
dispatchedIdBits, downId, mOrientedXPrecision, mOrientedYPrecision, mDownTime);
}
}
}