2013年9月16日 星期一

Unity3D研究院之IOS自定义游戏摇杆与飞机平滑的移动(十一)

http://www.xuanyusong.com/archives/526

移动开发游戏中使用到的触摸游戏摇杆在iPhone上是非常普遍的,毕竟是全触摸屏手机,今天MOMO 通过一个小例子和大家讨论Unity3D 中如何自定义一个漂亮的全触摸游戏摇杆。
       值得高兴的是,Unity3D 游戏引擎的标准资源中已经帮助我们封装了一个游戏摇杆脚本,所以实现部分的代码可以完全借助它的,具体调用需要我们自己来。
 Joystick.js是官方提供的脚本,具体代码如下,有兴趣的朋友可以仔细研究研究,MOMO就不多说啦。哇咔咔~

//////////////////////////////////////////////////////////////
// Joystick.js
// Penelope iPhone Tutorial
//
// Joystick creates a movable joystick (via GUITexture) that
// handles touch input, taps, and phases. Dead zones can control
// where the joystick input gets picked up and can be normalized.
//
// Optionally, you can enable the touchPad property from the editor
// to treat this Joystick as a TouchPad. A TouchPad allows the finger
// to touch down at any point and it tracks the movement relatively
// without moving the graphic
//////////////////////////////////////////////////////////////

@script RequireComponent( GUITexture )

// A simple class for bounding how far the GUITexture will move
class Boundary
{
 var min : Vector2 = Vector2.zero;
 var max : Vector2 = Vector2.zero;
}

static private var joysticks : Joystick[];     // A static collection of all joysticks
static private var enumeratedJoysticks : boolean = false;
static private var tapTimeDelta : float = 0.3;    // Time allowed between taps

var touchPad : boolean;          // Is this a TouchPad?
var touchZone : Rect;
var deadZone : Vector2 = Vector2.zero;      // Control when position is output
var normalize : boolean = false;        // Normalize output after the dead-zone?
var position : Vector2;          // [-1, 1] in x,y
var tapCount : int;           // Current tap count

private var lastFingerId = -1;        // Finger last used for this joystick
private var tapTimeWindow : float;       // How much time there is left for a tap to occur
private var fingerDownPos : Vector2;
private var fingerDownTime : float;
private var firstDeltaTime : float = 0.5;

private var gui : GUITexture;        // Joystick graphic
private var defaultRect : Rect;        // Default position / extents of the joystick graphic
private var guiBoundary : Boundary = Boundary();   // Boundary for joystick graphic
private var guiTouchOffset : Vector2;      // Offset to apply to touch input
private var guiCenter : Vector2;       // Center of joystick

function Start()
{
 // Cache this component at startup instead of looking up every frame
 gui = GetComponent( GUITexture );

 // Store the default rect for the gui, so we can snap back to it
 defaultRect = gui.pixelInset; 

    defaultRect.x += transform.position.x * Screen.width;// + gui.pixelInset.x; // -  Screen.width * 0.5;
    defaultRect.y += transform.position.y * Screen.height;// - Screen.height * 0.5;

    transform.position.x = 0.0;
    transform.position.y = 0.0;

 if ( touchPad )
 {
  // If a texture has been assigned, then use the rect ferom the gui as our touchZone
  if ( gui.texture )
   touchZone = defaultRect;
 }
 else
 {
  // This is an offset for touch input to match with the top left
  // corner of the GUI
  guiTouchOffset.x = defaultRect.width * 0.5;
  guiTouchOffset.y = defaultRect.height * 0.5;

  // Cache the center of the GUI, since it doesn't change
  guiCenter.x = defaultRect.x + guiTouchOffset.x;
  guiCenter.y = defaultRect.y + guiTouchOffset.y;

  // Let's build the GUI boundary, so we can clamp joystick movement
  guiBoundary.min.x = defaultRect.x - guiTouchOffset.x;
  guiBoundary.max.x = defaultRect.x + guiTouchOffset.x;
  guiBoundary.min.y = defaultRect.y - guiTouchOffset.y;
  guiBoundary.max.y = defaultRect.y + guiTouchOffset.y;
 }
}

function Disable()
{
 gameObject.active = false;
 enumeratedJoysticks = false;
}

function ResetJoystick()
{
 // Release the finger control and set the joystick back to the default position
 gui.pixelInset = defaultRect;
 lastFingerId = -1;
 position = Vector2.zero;
 fingerDownPosition = Vector2.zero;

 if ( touchPad )
  gui.color.a = 0.025;
}

function IsFingerDown() : boolean
{
 return (lastFingerId != -1);
}

function LatchedFinger( fingerId : int )
{
 // If another joystick has latched this finger, then we must release it
 if ( lastFingerId == fingerId )
  ResetJoystick();
}

function Update()
{
 if ( !enumeratedJoysticks )
 {
  // Collect all joysticks in the game, so we can relay finger latching messages
  joysticks = FindObjectsOfType( Joystick );
  enumeratedJoysticks = true;
 } 

 var count = Input.touchCount;

 // Adjust the tap time window while it still available
 if ( tapTimeWindow > 0 )
  tapTimeWindow -= Time.deltaTime;
 else
  tapCount = 0;

 if ( count == 0 )
  ResetJoystick();
 else
 {
  for(var i : int = 0;i < count; i++)
  {
   var touch : Touch = Input.GetTouch(i);
   var guiTouchPos : Vector2 = touch.position - guiTouchOffset;

   var shouldLatchFinger = false;
   if ( touchPad )
   {
    if ( touchZone.Contains( touch.position ) )
     shouldLatchFinger = true;
   }
   else if ( gui.HitTest( touch.position ) )
   {
    shouldLatchFinger = true;
   }  

   // Latch the finger if this is a new touch
   if ( shouldLatchFinger && ( lastFingerId == -1 ¦¦ lastFingerId != touch.fingerId ) )
   {

    if ( touchPad )
    {
     gui.color.a = 0.15;

     lastFingerId = touch.fingerId;
     fingerDownPos = touch.position;
     fingerDownTime = Time.time;
    }

    lastFingerId = touch.fingerId;

    // Accumulate taps if it is within the time window
    if ( tapTimeWindow > 0 )
     tapCount++;
    else
    {
     tapCount = 1;
     tapTimeWindow = tapTimeDelta;
    }

    // Tell other joysticks we've latched this finger
    for ( var j : Joystick in joysticks )
    {
     if ( j != this )
      j.LatchedFinger( touch.fingerId );
    }
   }    

   if ( lastFingerId == touch.fingerId )
   {
    // Override the tap count with what the iPhone SDK reports if it is greater
    // This is a workaround, since the iPhone SDK does not currently track taps
    // for multiple touches
    if ( touch.tapCount > tapCount )
     tapCount = touch.tapCount;

    if ( touchPad )
    {
     // For a touchpad, let's just set the position directly based on distance from initial touchdown
     position.x = Mathf.Clamp( ( touch.position.x - fingerDownPos.x ) / ( touchZone.width / 2 ), -1, 1 );
     position.y = Mathf.Clamp( ( touch.position.y - fingerDownPos.y ) / ( touchZone.height / 2 ), -1, 1 );
    }
    else
    {
     // Change the location of the joystick graphic to match where the touch is
     gui.pixelInset.x =  Mathf.Clamp( guiTouchPos.x, guiBoundary.min.x, guiBoundary.max.x );
     gui.pixelInset.y =  Mathf.Clamp( guiTouchPos.y, guiBoundary.min.y, guiBoundary.max.y );
    }

    if ( touch.phase == TouchPhase.Ended ¦¦ touch.phase == TouchPhase.Canceled )
     ResetJoystick();
   }
  }
 }

 if ( !touchPad )
 {
  // Get a value between -1 and 1 based on the joystick graphic location
  position.x = ( gui.pixelInset.x + guiTouchOffset.x - guiCenter.x ) / guiTouchOffset.x;
  position.y = ( gui.pixelInset.y + guiTouchOffset.y - guiCenter.y ) / guiTouchOffset.y;
 }

 // Adjust for dead zone
 var absoluteX = Mathf.Abs( position.x );
 var absoluteY = Mathf.Abs( position.y );

 if ( absoluteX < deadZone.x )
 {
  // Report the joystick as being at the center if it is within the dead zone
  position.x = 0;
 }
 else if ( normalize )
 {
  // Rescale the output after taking the dead zone into account
  position.x = Mathf.Sign( position.x ) * ( absoluteX - deadZone.x ) / ( 1 - deadZone.x );
 }

 if ( absoluteY < deadZone.y )
 {
  // Report the joystick as being at the center if it is within the dead zone
  position.y = 0;
 }
 else if ( normalize )
 {
  // Rescale the output after taking the dead zone into account
  position.y = Mathf.Sign( position.y ) * ( absoluteY - deadZone.y ) / ( 1 - deadZone.y );
 }
}





单击Create 创建一个GUI Texture,命名为Joy ,它用来显示游戏摇杆,如下图所示将摇杆的图片资源,与摇杆的脚本连线赋值给Joy.  Pixel Inset 中可以设置摇杆的显示位置与显示宽高。




到这一步 build and run 就可以在iPhone上看到这个游戏摇杆,并且可以通过触摸它,360度平滑过度。
在屏幕中绘制一个飞机,通过游戏摇杆去控制飞机的移动。
创建一个脚本,命名为Main.js 如下图所示  将 Main.js 、joy、plan 分别 绑定在Main Camera 上。


moveJoystick.position.x;
moveJoystick.position.y; 
这两个值是非常重要的两个信息,它们的取值范围是 -1 到 +1 ,表示 用户触摸摇杆的位置, 上 下 左 右 的信息。
//游戏摇杆对象
var moveJoystick : Joystick;

//飞机的贴图
var plan : Texture;

//飞机在屏幕中的坐标
var x = 0;
var y = 0;

//避免飞机飞出屏幕,分别是X、Y最大坐标,最小坐标是0、0
var cross_x = 0;
var cross_y = 0;

//飞机移动的速度
var planSpeed = 20;

function Start() {
 //初始化赋值
 x = 100;
 y = 100;
 cross_x = Screen.width -  plan.width;
 cross_y = Screen.height -  plan.height;

}

function Update () {
 //得到游戏摇杆的反馈信息,得到的值是 -1 到 +1 之间

  var touchKey_x =  moveJoystick.position.x;
  var touchKey_y =  moveJoystick.position.y;

  //摇杆向左
  if(touchKey_x == -1){
   x -= planSpeed;

  }
  //摇杆向右
  else if(touchKey_x == 1){
   x += planSpeed;

  }
  //摇杆向上
   if(touchKey_y == -1){
   y += planSpeed;

  }
  //摇杆向下
  else if(touchKey_y == 1){
   y -= planSpeed;

  }

  //防止飞机飞出屏幕,出界检测
  if(x < 0){
   x = 0;
  }else if(x > cross_x){
   x = cross_x;
  }

   if(y < 0){
   y = 0;
  }else if(y > cross_y){
   y = cross_y;
  }
}

function OnGUI () {

  //将飞机绘制在屏幕中
  GUI.DrawTexture(Rect(x,y,128,128),plan);  

}


导出 build and run  看看在iPhone 上的效果,通过触摸游戏摇杆可以控制飞机的移动啦,不错吧,哇咔咔~~



最后欢迎各位盆友可以和MOMO一起讨论Unity3D游戏开发,最近感冒的盆友越来越多,大家要多多注意身体健康噢。哇咔咔~~~ 附上Unity3D工程的下载地址,Xcode项目我就不上传了,须要的自己导出。