Mobile Input 移动设备输入

Unity iOS/Android offers you access to the iPhone, iPad and Android input systems via Input and iOS Input scripting interfaces.

Unity iOS/Android 为你提供访问iphone，iPad和Android的输入系统，通过Input 和 iOS Input脚本接口。

Input provides access to the multi-touch screen, accelerometer and device orientation. iOS Input provides access to geographical location.

Input提供访问多点触控屏幕，加速度和设备方向。iOS Input提供访问地理位置。

Access to keyboard on mobile devices is provided via the iOS keyboard.

访问键盘是通过iOS keyboard。

Multi-Touch Screen 多点触控屏幕

The iPhone and iPod Touch devices are capable of tracking up to five fingers touching the screen simultaneously. You can retrieve the status of each finger touching the screen during the last frame by accessing the Input.touches property array.

iPhone和iPod触控设备是具有五个手指触控屏幕同时跟踪能力。通过访问Input.touches属性数值，可以取回每个手指触摸屏幕在最后一帧的状态。

Each finger touch is represented by an Input.Touch data structure:

每个手指触控是通过Input.touches数据结构描述的：

• fingerId 手指索引
  The unique index for a touch. 统一触摸的唯一索引
• position 位置
  The screen position of the touch. 触摸屏幕的位置
• deltaPosition 增量位置
  The screen position change since the last frame. 自最后一帧改变的屏幕位置
• deltaTime 增量时间
  Amount of time that has passed since the last state change.
  从最后状态改变到现在经过的时间
• tapCount 点击数
  The iPhone/iPad screen is able to distinguish quick finger taps by the user. This counter will let you know how many times the user has tapped the screen without moving a finger to the sides. Android devices do not count number of taps, this field is always 1.
  iPhone/iPad屏幕能够识别用过的快速点击， 这个计数器让你知道用户点击屏幕多少次，而不是移动手指。android设备不对点击计数，这个方法总是返回1
• phase 相位（状态）
  Describes so called "phase" or the state of the touch. It can help you determine if the touch just began, if user moved the finger or if he just lifted the finger.
  描述触摸的状态，可以帮助开发者确定用户是否刚开始触摸，是否用户移动手指，是否用户刚刚抬起手指。

Phase can be one of the following:

相位（状态）可能是下列之一：

• Began 开始
  A finger just touched the screen. 手指刚刚触摸屏幕
• Moved 移动
  A finger moved on the screen. 手指在屏幕上移动
• Stationary 静止
  A finger is touching the screen but hasn't moved since the last frame.
  手指触摸屏幕，但是自最后一帧没有移动
• Ended 结束
  A finger was lifted from the screen. This is the final phase of a touch.
  手指从屏幕上抬起，这是触控的最后状态。
• Canceled 取消
  The system cancelled tracking for the touch, as when (for example) the user puts the device to her face or more than five touches happened simultaneously. This is the final phase of a touch.
  系统取消了触控跟踪，如，用户将设备放在了脸上或超过同时超过5个触摸点。这是触控的最后状态。

Following is an example script which will shoot a ray whenever the user taps on the screen:

下面的例子，只要用户在屏幕上点击，将射出一条光线：

var particle : GameObject;
function Update () {
	for (var touch : Touch in Input.touches) {
		if (touch.phase == TouchPhase.Began) {
			// Construct a ray from the current touch coordinates
			//从当前的触摸坐标建一条光线
			var ray = Camera.main.ScreenPointToRay (touch.position);
			if (Physics.Raycast (ray)) {
				// Create a particle if hit
				//如果触摸就创建一个例子
				Instantiate (particle, transform.position, transform.rotation);
			}
		}
	}
}

Mouse Simulation 鼠标模拟

On top of native touch support Unity iOS/Android provides a mouse simulation. You can use mouse functionality from the standard Input class.

除了原有的触控之外，Unity iOS/Android还提供了鼠标模拟。从标准的Input类中，可以使用鼠标功能。

Device Orientation 设备方向

Unity iOS/Android allows you to get discrete description of the device physical orientation in three-dimensional space. Detecting a change in orientation can be useful if you want to create game behaviors depending on how the user is holding the device.

Unity iOS/Android 可以获取设备在现实三维空间的物理方向。检测方向改变用于， 如果你想根据用户怎样手持设备来创建游戏行为。

You can retrieve device orientation by accessing the Input.deviceOrientation property. Orientation can be one of the following:

通过访问Input.deviceOrientation属性，能检索设备的方向。方向值可能是下列之一：

• Unknown 未知
  The orientation of the device cannot be determined. For example when device is rotate diagonally.
  不能确定设备的方向，例如，当设备正好旋转为对角时。
• Portrait 纵向
  The device is in portrait mode, with the device held upright and the home button at the bottom.
  设备在纵向模式，设备在直立状态，home按钮在底部
• PortraitUpsideDown 纵向倒置
  The device is in portrait mode but upside down, with the device held upright and the home button at the top.
  设备在纵向模式，但为倒置，设备在直立状态，home按钮在顶部
• LandscapeLeft 左横向
  The device is in landscape mode, with the device held upright and the home button on the right side.
  设备为横向模式，设备为直立状态，并home按钮在右边
• LandscapeRight 右横向
  The device is in landscape mode, with the device held upright and the home button on the left side.
  设备为横向模式，设备为直立状态，并home按钮在左边
• FaceUp 面向上
  The device is held parallel to the ground with the screen facing upwards.
  设备与地面平行，并屏幕面朝上
• FaceDown 面向下
  The device is held parallel to the ground with the screen facing downwards.
  设备与地面平行，并屏幕面朝下

Accelerometer 加速度传感器

As the mobile device moves, a built-in accelerometer reports linear acceleration changes along the three primary axes in three-dimensional space. Acceleration along each axis is reported directly by the hardware as G-force values. A value of 1.0 represents a load of about +1g along a given axis while a value of -1.0 represents -1g. If you hold the device upright (with the home button at the bottom) in front of you, the X axis is positive along the right, the Y axis is positive directly up, and the Z axis is positive pointing toward you.

在手机设备移动时，内置加速度传感器报告在三维空间，沿着三个主要轴上的线性加速度改变。沿着每个轴的加速度由硬件作为G-force值直接报告。值为1表示沿给定轴增加1g负载，值为-1.0表示减少1g。如果用户在面前竖直拿着设备（home按钮在底部），X轴指向右，Y轴指向上，Z轴指向前。

You can retrieve the accelerometer value by accessing the Input.acceleration property.

可以通过访问Input.acceleration属性，取回加速度传感器的值。

The following is an example script which will move an object using the accelerometer:

下面的例子，将使用加速度传感器移动一个物体：

var speed = 10.0;
function Update () {
	var dir : Vector3 = Vector3.zero;

	// we assume that the device is held parallel to the ground
	// and the Home button is in the right hand
	//假设该设备与地面平行，Home按钮在右边
	// remap the device acceleration axis to game coordinates:
	//重新映射设备加速度轴到游戏坐标：
	//  1) XY plane of the device is mapped onto XZ plane
	//		设备的XY平面映射到XZ平面
	//  2) rotated 90 degrees around Y axis
	//		沿着Y轴旋转90度
	dir.x = -Input.acceleration.y;
	dir.z = Input.acceleration.x;

	// clamp acceleration vector to the unit sphere
	//钳制加速度向量到单位球
	if (dir.sqrMagnitude > 1)
		dir.Normalize();

	// Make it move 10 meters per second instead of 10 meters per frame...
	//使它每秒移动10米，而不是每帧10米
	dir *= Time.deltaTime;

	// Move object 移动物体
	transform.Translate (dir * speed);
}

Low-Pass Filter 低通过滤器

Accelerometer readings can be jerky and noisy. Applying low-pass filtering on the signal allows you to smooth it and get rid of high frequency noise.

加速度传感器数值可能被颠簸和噪音影响。应用低通过滤器在信号上可以是它平滑，并摆脱高频噪音的干扰。

The following script shows you how to apply low-pass filtering to accelerometer readings:

下面的例子显示，怎样应用低通到加速度传感器数值：

var AccelerometerUpdateInterval : float = 1.0 / 60.0;
var LowPassKernelWidthInSeconds : float = 1.0;

private var LowPassFilterFactor : float = AccelerometerUpdateInterval / LowPassKernelWidthInSeconds; // tweakable
private var lowPassValue : Vector3 = Vector3.zero;
function Start () {
	lowPassValue = Input.acceleration;
}

function LowPassFilterAccelerometer() : Vector3 {
	lowPassValue = Mathf.Lerp(lowPassValue, Input.acceleration, LowPassFilterFactor);
	return lowPassValue;
}

The greater the value of LowPassKernelWidthInSeconds, the slower the filtered value will converge towards the current input sample (and vice versa). You should be able to use the LowPassFilter() function instead of avgSamples().

LowPassKernelWidthInSeconds的值越大， 被过滤值将汇集当前输入采样越慢，反之亦然。应该使用LowPassFilter（）函数，而不是avgSamples（）。

I'd like as much precision as possible when reading the accelerometer. What should I do?
我想尽可能的读取加速度传感器的更高精度。我应该怎样做呢？

Reading the Input.acceleration variable does not equal sampling the hardware. Put simply, Unity samples the hardware at a frequency of 60Hz and stores the result into the variable. In reality, things are a little bit more complicated -- accelerometer sampling doesn't occur at consistent time intervals, if under significant CPU loads. As a result, the system might report 2 samples during one frame, then 1 sample during the next frame.

读取 Input.acceleration变量，不等于从硬件采样。简而言之，Unity硬件样品频率为60Hz并储存结果到变量。在现实中，是一个有点复杂的东西--加速度传感器采样不会发生在一致的时间间隔，如果大量的CPU负荷的情况下，因此，系统可能会报告一帧中的2个采样，那么1个采样在下一帧。

You can access all measurements executed by accelerometer during the frame. The following code will illustrate a simple average of all the accelerometer events that were collected within the last frame:

通过加速度传感器在帧间可以访问所有测量。

var period : float = 0.0;
var acc : Vector3 = Vector3.zero;
for (var evnt : iPhoneAccelerationEvent  in iPhoneInput.accelerationEvents) {
	acc += evnt.acceleration * evnt.deltaTime;
	period += evnt.deltaTime;
}
if (period > 0)
	acc *= 1.0/period;
return acc;

Further Reading 深入阅读

The Unity mobile input API is originally based on Apple's API. It may help to learn more about the native API to better understand Unity's Input API. You can find the Apple input API documentation here:

Unity移动Input API本来是基于Apple's API。这可以帮助你学习更多关于原生API，更好的理解Untiy的Input API。在这里找到Apple的 Input API文档：

• Programming Guide: Event Handling (Apple iPhone SDK documentation)
• UITouch Class Reference (Apple iOS SDK documentation)

Note: The above links reference your locally installed iPhone SDK Reference Documentation and will contain native ObjectiveC code. It is not necessary to understand these documents for using Unity on mobile devices, but may be helpful to some!

注意：上面的链接参考你本地安装的iPHone SDK参考文档，也将包含ObjectiveC代码。对于在移动设备使用Unity开发，没有必要理解这些文档，但是可能或许有些一下帮助。

最近更新：2011-05-19