Kinect with Unity3D游戏开发的一点思路总结（体感赛车游戏）

Unity3D是一个非常成熟的3D引擎；Kinect可以理解为一个输入设备（像鼠标键盘一样）所以这里技术上的关键点是：将输入信号与3D图形控制结合起来

设计上的关键点是：构造正常人会在2—3平方米的面积内通常可以做的事情（比如让普通人在这个范围内挥动手臂切水果、罚点球、垫排球等等）

这些是笔者这几天接触Kinect with Unity3D以来的最大感受吧。（为什么使用Unity3D呢；因为它含有丰富的例程和已开发资源，所以初期适宜用来移植合适的游戏到Kinect上）

对于第二点，我想也是每一个Kinect人都在探索和寻找创意的；

而第一点，笔者刚玩这俩东西，稍稍分享一些思路。在Unity3D当中，笔者主要是利用了KinectPointController.cs这个官方提供的脚本。

这个脚本实现了识别全身各个关键部位，那么理论上我们只要将这些量通过某种转化关系之后，用来控制Unity3D已有的各个元素，就完成了任务。笔者因此进行了这方面的尝试，得益于Unity3D非常丰富的Sample，笔者选取官方的Car Tutorial进行改造。我们要做的就是根据识别部位的结果，将动作映射到汽车控制的指令，而后进行不断的测试和优化用户体验，即可。

笔者将KinectPointController.cs所挂的PointMan这个包挂在Car上，这样他们就可以一起移动，而后笔者目前只用到左右手、头和脚这几点，因此在unity中不显示PointMan的其他几点mesh。

在unity中通过KinectPointController.cs识别PointMan各点相对Car中心的坐标值，而后进行分析，笔者选取了若干个姿势，包括转方向盘，前倾踩油门和后倾踩刹车及挂倒档，通过试验正确识别后，下面剩下的就是模拟键盘鼠标控制Car的结果了。

在Car tutorial这个示例中，车子的油门和方向盘主要通过Car.js这个脚本中的throttle和steer来进行控制，而KinectPointController.cs是C#脚本，这就涉及C#对js中变量值的操作。Unity支持这样的操作。

笔者先将Car.js移到"Pro Standard Assets”目录下，然后修改上面两个变量为全局变量，而后直接可以在C#中调用Car.js的全局变量。为什么这样做可以参考官方文档：
http://docs.unity3d.com/Documentation/ScriptReference/index.Script_compilation_28Advanced29.html

因此再辅以对Unity3D图形界面下的若干设置和操作，就完成了目前的体感赛车demo，而剩下的就是根据用户体验对操控方式进行优化。

最后附上目前使用的修改后的KinectPointController.cs脚本，其中含有笔者目前对Car.js脚本中变量的操作方式

1. /*
   
2. * KinectModelController.cs - Moves every 'bone' given to match
   
3. * the position of the corresponding bone given by
   
4. * the kinect. Useful for viewing the point tracking
   
5. * in 3D.
   
6. * 
   
7. * Developed by Peter Kinney -- 6/30/2011
   
8. * 
   
9. * ____________________________________________
   
10. *
    
11. * Modified By Chen Zhehuai@Dian -- 11/2/2012
    
12. */
    
13. 
    
14. using UnityEngine;
    
15. using System;
    
16. using System.Collections;
    
17. 
    
18. public class KinectPointController : MonoBehaviour 
    
19. {
    
20. 
    
21. //Assignments for a bitmask to control which bones to look at and which to ignore
    
22. public enum BoneMask
    
23. {
    
24. None = 0x0,
    
25. Hip_Center = 0x1,
    
26. Spine = 0x2,
    
27. Shoulder_Center = 0x4,
    
28. Head = 0x8,
    
29. Shoulder_Left = 0x10,
    
30. Elbow_Left = 0x20,
    
31. Wrist_Left = 0x40,
    
32. Hand_Left = 0x80,
    
33. Shoulder_Right = 0x100,
    
34. Elbow_Right = 0x200,
    
35. Wrist_Right = 0x400,
    
36. Hand_Right = 0x800,
    
37. Hip_Left = 0x1000,
    
38. Knee_Left = 0x2000,
    
39. Ankle_Left = 0x4000,
    
40. Foot_Left = 0x8000,
    
41. Hip_Right = 0x10000,
    
42. Knee_Right = 0x20000,
    
43. Ankle_Right = 0x40000,
    
44. Foot_Right = 0x80000,
    
45. All = 0xFFFFF,
    
46. Torso = 0x10000F, //the leading bit is used to force the ordering in the editor
    
47. Left_Arm = 0x1000F0,
    
48. Right_Arm = 0x100F00,
    
49. Left_Leg = 0x10F000,
    
50. Right_Leg = 0x1F0000,
    
51. R_Arm_Chest = Right_Arm | Spine,
    
52. No_Feet = All & ~(Foot_Left | Foot_Right)
    
53. }
    
54. 
    
55. public SkeletonWrapper sw;
    
56. 
    
57. public GameObject Hip_Center;
    
58. public GameObject Spine;
    
59. public GameObject Shoulder_Center;
    
60. public GameObject Head;
    
61. public GameObject Shoulder_Left;
    
62. public GameObject Elbow_Left;
    
63. public GameObject Wrist_Left;
    
64. public GameObject Hand_Left;
    
65. public GameObject Shoulder_Right;
    
66. public GameObject Elbow_Right;
    
67. public GameObject Wrist_Right;
    
68. public GameObject Hand_Right;
    
69. public GameObject Hip_Left;
    
70. public GameObject Knee_Left;
    
71. public GameObject Ankle_Left;
    
72. public GameObject Foot_Left;
    
73. public GameObject Hip_Right;
    
74. public GameObject Knee_Right;
    
75. public GameObject Ankle_Right;
    
76. public GameObject Foot_Right;
    
77. 
    
78. private GameObject[] _bones; //internal handle for the bones of the model
    
79. //private Vector4[] _bonePos; //internal handle for the bone positions from the kinect
    
80. 
    
81. public int player;
    
82. public BoneMask Mask = BoneMask.All;
    
83. 
    
84. // Use this for initialization
    
85. void Start () {
    
86. //store bones in a list for easier access
    
87. _bones = new GameObject[(int)Kinect.NuiSkeletonPositionIndex.Count] {Hip_Center, Spine, Shoulder_Center, Head,
    
88. Shoulder_Left, Elbow_Left, Wrist_Left, Hand_Left,
    
89. Shoulder_Right, Elbow_Right, Wrist_Right, Hand_Right,
    
90. Hip_Left, Knee_Left, Ankle_Left, Foot_Left,
    
91. Hip_Right, Knee_Right, Ankle_Right, Foot_Right};
    
92. //_bonePos = new Vector4[(int)BoneIndex.Num_Bones];
    
93. 
    
94. 
    
95. 
    
96. 
    
97. }
    
98. 
    
99. // Update is called once per frame
    
100. void Update () {
     
101. Vector3 leftHand = new Vector3(0,0,0);
     
102. Vector3 rightHand = new Vector3(0,0,0);
     
103. Vector3 HipCenter = new Vector3(0,0,0);
     
104. Vector3 HeadCenter = new Vector3(0,0,0);
     
105. Vector3 FootLeft = new Vector3(0,0,0);
     
106. Vector3 FootRight = new Vector3(0,0,0);
     
107. 
     
108. //update all of the bones positions
     
109. if (sw.pollSkeleton())
     
110. {
     
111. Debug.Log("Has Track\n");
     
112. for( int ii = 0; ii < (int)Kinect.NuiSkeletonPositionIndex.Count; ii++) 
     
113. {
     
114. //_bonePos[ii] = sw.getBonePos(ii);
     
115. if( ((uint)Mask & (uint)(1 << ii) ) > 0 ){
     
116. _bones[ii].transform.localPosition = sw.bonePos[player,ii];
     
117. }
     
118. //hip center
     
119. if(ii == 0)
     
120. {
     
121. HipCenter = _bones[ii].transform.localPosition;
     
122. // Debug.Log("Hip: x " + _bones[ii].transform.localPosition.x.ToString() + " y " + 
     
123. // _bones[ii].transform.localPosition.y.ToString() + " z " +_bones[ii].transform.localPosition.z.ToString()); 
     
124. 
     
125. }
     
126. //head center
     
127. if(ii == 3)
     
128. {
     
129. HeadCenter = _bones[ii].transform.localPosition;
     
130. // Debug.Log("Head: x " + _bones[ii].transform.localPosition.x.ToString() + " y " + 
     
131. // _bones[ii].transform.localPosition.y.ToString() + " z " +_bones[ii].transform.localPosition.z.ToString()); 
     
132. }
     
133. //foot left
     
134. if(ii == 15)
     
135. {
     
136. FootLeft = _bones[ii].transform.localPosition;
     
137. // Debug.Log("LeftFoot: x " + _bones[ii].transform.localPosition.x.ToString() + " y " + 
     
138. // _bones[ii].transform.localPosition.y.ToString() + " z " +_bones[ii].transform.localPosition.z.ToString()); 
     
139. }
     
140. if(ii == 19)
     
141. {
     
142. FootRight = _bones[ii].transform.localPosition;
     
143. // Debug.Log("RightFoot: x " + _bones[ii].transform.localPosition.x.ToString() + " y " + 
     
144. // _bones[ii].transform.localPosition.y.ToString() + " z " +_bones[ii].transform.localPosition.z.ToString()); 
     
145. }
     
146. //Right hand
     
147. if(ii == 11)
     
148. {
     
149. rightHand = _bones[ii].transform.localPosition;
     
150. // Debug.Log("RightHand: x " + _bones[ii].transform.localPosition.x.ToString() + " y " + 
     
151. // _bones[ii].transform.localPosition.y.ToString() + " z " +_bones[ii].transform.localPosition.z.ToString()); 
     
152. }
     
153. //left hand
     
154. if(ii == 7)
     
155. {
     
156. leftHand = _bones[ii].transform.localPosition;
     
157. // Debug.Log("LeftHand: x " + _bones[ii].transform.localPosition.x.ToString() + " y " + 
     
158. // _bones[ii].transform.localPosition.y.ToString() + " z " +_bones[ii].transform.localPosition.z.ToString());
     
159. 
     
160. }
     
161. 
     
162. }
     
163. 
     
164. 
     
165. //Event.KeyboardEvent("w");
     
166. 
     
167. //Car.throttle = 0.5f;
     
168. 
     
169. //Car.throttle = 0;
     
170. //Car.steer = 0;
     
171. 
     
172. //left hand y+z >2 ;right hand y+z <2 右转
     
173. if ((leftHand.y + leftHand.z > 2) && (rightHand.y + leftHand.z < 2))
     
174. {
     
175. //右转
     
176. Car.steer = 1f;
     
177. //Car.throttle = 0.5f;
     
178. Debug.Log("Right Turn\n");
     
179. }
     
180. if ((leftHand.y + leftHand.z < 2) && (rightHand.y + leftHand.z > 2))
     
181. {
     
182. //左转
     
183. Car.steer = -1f;
     
184. //Car.throttle = 0.5f;
     
185. Debug.Log("Left Turn\n");
     
186. }
     
187. /* 倒车-》后倾；油门-》前倾 */
     
188. if ((HeadCenter.x > HipCenter.x + 0.06))
     
189. {
     
190. Debug.Log("UPUP\n");
     
191. Car.throttle = Car.throttle + 0.015f;
     
192. if (Car.throttle > 1)
     
193. Car.throttle = 1;
     
194. }
     
195. if ((HeadCenter.x < HipCenter.x) && (FootRight.x < HipCenter.x))
     
196. {
     
197. Debug.Log("DOWNdown\n");
     
198. Car.throttle = Car.throttle - 0.015f;
     
199. if (Car.throttle < -1)
     
200. Car.throttle = -1;
     
201. }
     
202. 
     
203. Debug.Log("CS-thro " + Car.throttle); 
     
204. Debug.Log("CS-stee " + Car.steer); 
     
205. 
     
206. }
     
207. else
     
208. {
     
209. Car.throttle = 0f;
     
210. Debug.Log("Not Track--Down\n");
     
211. }
     
212. }
     
213. }