[SOLVED] transform.position randomly thrown to the end of the universe?

Hey everyone -
I have a bizarre problem that I'm willing to accept is n00bishness - if anyone can find the cause...

I'm building my first title a 3d plane game destined for mobile.

The most distressing issue so far is that when testing, I've seen the player gameObject's transform thrown to the 'far reaches' of the game universes (space.world?).

It's as if transform.position is given a "maximum possible value" somewhere along the way?


To work around this issue, I have temporary created "resets" that return the player's game object back to the "playable area". These resets are commented out with "$$$$$$$$$$$$$$$$$$$" so that they stand out


AirplaneMovement.js

Code (JavaScript):

1. //This script is used to determine base movement of the airplane
2.  
3. #pragma strict
4.  
5.  
6. // Variables used for tuning airplane's behaviour
7. var SpeedMultiplierBank : float = 150.0;            // Speed at which the airplane moves from side to side
8. var SpeedMultiplierPower : float = 250.0;            // Speed at which the airplane accelerates
9. var BarrelRollSeverity: float = 450.0;                // Speed of a barrel roll
10. var RollRate: float = 150.0;                        // Plane's "roll rate' - used to determine banking roll
11. var RollRateReverse : float = 300.0;                // used when going from already rolled over to opposite roll
12.  
13.  
14. // Variables used for defining the 'play area'
15.  
16. // if we've drifted too far, use these vars to reset us back into 'play space'
17. // later we will change this so that the 'play space' is calculated based on
18. // screen gemotry - currently using an iPhone 5s in Portrait to work it out
19. // the 'work out play space' function will be in a 'control centre' game object
20. // we will copy these variables here
21.  
22. var PosXposMax : float = 38.0;
23. var PosXnegMax : float = -38.0;
24. var PosYposMax : float = 71.0;
25. var PosYnegMax : float = -71.0;
26.  
27.  
28. //calculate reset positions once for performance reasons
29. //down the track these 'screen padding' values will also
30. //be kept in the 'control centre' object, however we're
31. //using iPhone 5s as development platform
32.  
33. private var PosXposReset : float = PosXposMax - 0.5;
34. private var PosXnegReset : float = PosXnegMax + 0.5;
35. private var PosYposReset : float = PosYposMax - 0.5;
36. private var PosYnegReset : float = PosYnegMax + 0.5;
37.  
38.  
39.  
40. //used for stopping automatic resets on airplane position/rotation when a manouvre is in progress
41. private var BankInProgress : boolean = false;
42. private var RollInProgress : boolean = false;
43. var LoopInProgress : boolean = false;
44. var LoopAroundPoint = Vector3(0,0,0);
45. var LoopStartPoint = Vector3(0,0,0);
46. var LoopAroundDirection = Vector3(0,0,0);
47.  
48.  
49.  
50.  
51. // loop the loop variables
52. var LoopManouvreSpeed : float = 75;                    // speed the plane travels through loop-the-loop
53. var NoseDown : boolean = false;                        // used to determine 'direction' of loop-the-loop - nose down or nose up
54. var MaxPoint : float;                        // used to determine the maximum point the plane will loop-the-loop through
55. var MaxPointReached : boolean = false;        // used for logic to ensure one loop-the-loop per script execution
56.  
57.  
58.  
59. function Start () {
60.  
61.     //calculate reset positions once for performance reasons
62.     //down the track these 'screen padding' values will also
63.     //be kept in the 'control centre' object, however we're
64.     //using iPhone 5s as development platform
65.  
66.     PosXposReset = PosXposMax - 0.5;
67.     PosXnegReset = PosXnegMax + 0.5;
68.     PosYposReset = PosYposMax - 0.5;
69.     PosYnegReset = PosYnegMax + 0.5;
70.  
71. }
72.  
73.  
74.  
75. function BankAirplane(attitude:float){
76.     // banks the airplane and moves it in the correction direction.
77.     // amount is the amount of the bank
78.  
79.     if (LoopInProgress == false){
80.          
81.         if (attitude > 0) RepositionAirplane(1,0);
82.         if (attitude < 0) RepositionAirplane(-1,0);
83.      
84.         //bank the plane
85.      
86.         //this starts the process to bank the plane right
87.         if (attitude > 0 && transform.localEulerAngles.z <1) transform.Rotate(0,0,-RollRate * Time.deltaTime);
88.              
89.         else if (attitude > 0 && transform.localEulerAngles.z + 180 > 359){
90.              
91.                 if (transform.localEulerAngles.z >320) transform.Rotate(0,0,-RollRate * Time.deltaTime);         //we're banked on the correct side, bank at normal rate
92.                 if (transform.localEulerAngles.z <40) transform.Rotate(0,0,-RollRateReverse * Time.deltaTime);     //we're banked on the opposite direction, bank over quickly
93.             }
94.                  
95.                  
96.                  
97.             //the following else-if banks the plane left
98.             else if (attitude < 0 && transform.localEulerAngles.z + 180 <360) {
99.                 if (transform.localEulerAngles.z <40) transform.Rotate(0,0,RollRate * Time.deltaTime);             //we're on the correct side, bank at normal rate
100.                 if (transform.localEulerAngles.z >320) transform.Rotate(0,0,RollRateReverse * Time.deltaTime);     //we're banked in the opposite direction, bank over quickly
101.                  
102.             }
103.      
104.         }
105.      
106.      
107.         //reset the bank speed back to positive if we made it negative (this is to make things easier next barrel roll)
108.         if (SpeedMultiplierBank < 0) SpeedMultiplierBank = SpeedMultiplierBank * -1;
109.      
110. }
111.  
112.  
113.  
114.  
115.  
116. function DoBarrelRoll(attitude: float){
117.     // this function is for doing barrel rolls!
118.  
119.     if (LoopInProgress == false){
120.         if (attitude < 0) BarrelRollSeverity = BarrelRollSeverity * -1;
121.      
122.         transform.Rotate(0,0, BarrelRollSeverity * Time.deltaTime);
123.      
124.         if (BarrelRollSeverity < 0) BarrelRollSeverity = BarrelRollSeverity * -1;
125.     }
126.  
127. }
128.  
129.  
130. function CommenceLoopTheLoop (noseDirection: boolean) {        //take the direction of the 'swipe'
131.  
132.     // This is the function which starts the Loop the Loop manouvre
133.     // It was originally created to let a finger-swipe trigger
134.     // a loop-the-loop in either nose-down or nose-up position
135.  
136.     if (LoopInProgress == false){
137.         var PlayerCurrentPosition = Vector3(0,0,0);
138.         PlayerCurrentPosition = gameObject.transform.position;
139.         LoopStartPoint = PlayerCurrentPosition;
140.      
141.         if (noseDirection == true) {
142.             NoseDown = true;        //used in update() to determine tests for ending loop-the-loop
143.             LoopAroundPoint = PlayerCurrentPosition - Vector3(0,20,0); //calculate the position we're going to loop-the-loop around
144.             LoopAroundDirection = Vector3(1.0,0); //The Unity doco calls this "axis", from what I can tell it's what part of you rotates
145.             MaxPoint = -40;            //used in update() to determine tests for ending loop-the-loop
146.             }
147.         else {
148.             NoseDown = false;            //used in update() to determine tests for ending loop-the-loop
149.             LoopAroundPoint = PlayerCurrentPosition + Vector3(0,20,0); //calculate the position we're going to loop-the-loop around
150.             LoopAroundDirection = Vector3(-1,0,0); //The Unity doco calls this "axis", from what I can tell it's what part of you rotates
151.             MaxPoint = 40;                //used in update() to determine tests for ending loop-the-loop
152.             }
153.      
154.             MaxPointReached = false;    //used in update() to determine tests for ending loop-the-loop
155.             LoopInProgress = true;         //used in update() to prevent the plane from performing other manouvres
156.     }
157.  
158. }
159.  
160.  
161.  
162.  
163. function PowerIncrease() {
164. //This function is called by the controller's script in it's update.
165. //used for moving the airplane forward on the screen & increasing it's speed
166.  
167.     if (LoopInProgress == false) RepositionAirplane(0,1);
168.  
169. }
170.  
171.  
172. function PowerDecrease() {
173. //This function is called by the controller's script in it's update.
174. //used for moving the airplane backwards on the screen & decreasing it's speed
175.  
176.     if (LoopInProgress == false) RepositionAirplane(0,-1);
177.  
178. }
179.  
180.  
181.  
182. function RepositionAirplane (attitude: float, power: float) {
183. //these parameters are only used for 'direction' of input - there are
184. //tuning variables for adjusting speed.
185.  
186.     if (LoopInProgress == false){
187.         //variables for reading the plane's current position in world space
188.         var PositionX : float = transform.position.x;
189.         var PositionY : float = transform.position.y;
190.         var PositionZ : float = transform.position.z;
191.  
192.      
193.         var DestX: float;    // our X destination
194.         var DestZ: float;    // our Z destination
195.      
196.         //if we're going left, we need negative speed applied left
197.         if (attitude < 0) SpeedMultiplierBank = SpeedMultiplierBank * -1;
198.         if (power < 0) SpeedMultiplierPower = SpeedMultiplierPower * -1;
199.      
200.         //work out what our destination X point is
201.         DestX = PositionX + (SpeedMultiplierBank * Time.deltaTime);
202.         DestZ = PositionZ + (SpeedMultiplierPower * Time.deltaTime);
203.      
204.         //if destination X point is within 'playable bound'
205.         if (attitude !=0 && DestX > PosXnegMax && DestX < PosXposMax){
206.  
207.      
208.             transform.Translate(SpeedMultiplierBank * Time.deltaTime, PositionY, PositionZ, Space.World);  //move the plane along the X access
209.      
210.         }
211.      
212.         if (power !=0 && DestZ > PosYnegMax && DestZ < PosYposMax){
213.        
214.             transform.Translate(PositionX, PositionY, SpeedMultiplierPower * Time.deltaTime, Space.World);  //move the plane along the Z access
215.      
216.         }
217.      
218.         // return these back to positive value for next time.
219.         if (SpeedMultiplierBank < 0) SpeedMultiplierBank = SpeedMultiplierBank * -1;
220.         if (SpeedMultiplierPower < 0) SpeedMultiplierPower = SpeedMultiplierPower * -1;
221.  
222.  
223.     }
224. }
225.  
226.  
227. function ResetAirplane(){
228.     // This function resets the airplane's attitude & altitude back to 'zero' gracefully
229.     // The idea for this function is that it manouvres the plane back to 'straight and level' flight
230.  
231.     if (LoopInProgress == false) {
232.         if (transform.localEulerAngles.z > 5 && transform.localEulerAngles.z <=180) transform.Rotate(0,0,-150 * Time.deltaTime);
233.         if (transform.localEulerAngles.z >180) transform.Rotate(0,0,150 * Time.deltaTime);
234.         if (transform.localEulerAngles.z <=5) transform.Rotate(0,0,-transform.localEulerAngles.z);
235.     }
236.  
237.  
238. }
239.  
240. function Update() {
241.  
242.  
243.     // start ============= Various frame-based resets =============
244.      // if we're not performing a loop the loop, then set reset our altitude
245.       if (LoopInProgress == false) {
246.      
247.          // if we're wandered outside of playable bounds, move the airplane back to the appropriate edge
248.        
249.        
250.          // $$$$$$$$$$$$$$$$$$$ When these are commented out (ie no resets) my player transform is thrown to
251.          // $$$$$$$$$$$$$$$$$$$ the edge of the space.world - as if the transform.position is assigned max
252.          // $$$$$$$$$$$$$$$$$$$ float value.
253.        
254.          /*
255.        
256.         if (transform.position.x < PosXnegMax) {
257.                     print("#### Reset X- ####");
258.                     print("Transform X: " + transform.position.x);
259.                     print("Reset To: " + PosXnegReset);
260.                     transform.position.x = PosXnegReset;
261.                     print("#### Reset X- ####");};
262.                  
263.         if (transform.position.x > PosXposMax) {
264.                     print("#### Reset X+ ####");
265.                     print("Transform X: " + transform.position.x);
266.                     print("Reset To: " + PosXposReset);
267.                     transform.position.x = PosXposReset;
268.                     print("#### Reset X+ ####");};
269.                  
270.         if (transform.position.z < PosYnegMax) {
271.                     print("#### Reset Z- ####");
272.                     print("Transform Z: " + transform.position.z);
273.                     print("Reset To: " + PosYnegReset);
274.                     transform.position.z = PosYnegReset;
275.                     print("#### Reset Z- ####");};
276.                  
277.         if (transform.position.z > PosYposMax) {
278.                        print("#### Reset Z+ ####");
279.                        print("Transform Z: " + transform.position.z);
280.                        print("Reset To: " + PosYposReset);
281.                     transform.position.z = PosYposReset;
282.                     print("#### Reset Z+ ####");};
283.                  
284.         */
285.         // $$$$$$$$$$$$$$$$$$$ this is the end of the section you need to comment out to see this behaviour          
286.        
287.           transform.position.y = 0;
288.           transform.rotation.x = 0;}
289.    
290.       // end ============= Various frame-based resets =============
291.    
292.    
293.    
294.       // start ============= Loop the loop ============
295.       //     This code exists to move the airplane in each frame - it works with function CommenceLoopTheLoop()
296.       //  because we only want to do this when we're meant to be performing a loop the loop. There is also
297.       //  code in the 'various frame-based resets' section which keeps the invisible objects aligned with the
298.       //  airplane.  We also don't want the plane resetting position during a loop-the-loop
299.    
300.     if (LoopInProgress == true) {
301.  
302.         var distToStart : float = Vector3.Distance(LoopStartPoint, gameObject.transform.position);
303.         //print("Distance from Loop Start Point - " + distToStart);
304.  
305.         //move and rotate the plane  
306.         transform.RotateAround (LoopAroundPoint, LoopAroundDirection, LoopManouvreSpeed * Time.deltaTime);
307.      
308.         //if this the first time we've reached the max point, set Max Point reached to true
309.         if (MaxPointReached == false && distToStart >39.0) MaxPointReached = true;
310.      
311.         //if we're at zero, and we've already been through the max point, then the manouvre is complete
312.         if (MaxPointReached == true && distToStart <1.0) LoopInProgress = false;
313.      
314.      
315.     }
316.  
317.     // end ============= Loop the loop =============
318.    
319.  
320. }
321.  

GyroInput.js

Code (JavaScript):

1. #pragma strict
2.  
3. //threshold values for this controller type (Gyro)
4.  
5. var TestingSpeed : float = 10;
6.  
7. var Player : GameObject;
8. var PlayerMovement : Component;
9.  
10. var GyroYDeadNeg : float = -0.1;            //used to determine negative deadspot on Y axis
11. var GyroYDeadPos : float = 0.1;                //used to determine positive deadspot on Y axis
12.  
13. var GyroXDeadNeg : float = -0.1;
14. var GyroXDeadPos : float = 0.1;
15.  
16. var GyroBarrelRollNeg : float = -0.35;        //at what rotation does barrel roll start?
17. var GyroBarrelRollPos : float = 0.35;        //at what rotation does barrel roll start
18.  
19.  
20. // Tuning Variables
21. var RollSpeed : float = 3.0;
22. var BankPower : float = 10.0;
23.  
24.  
25.  
26.  
27. private var GyroOffset : Vector3;
28. private var GyroAttitude : Quaternion;
29. private var GyroRotation : Vector3;
30. private var MaxRotationRate : float;
31. private var MinRotationRate : float;
32.  
33. private var MovementScript : Component;
34.  
35.  
36. function Start () {
37.  
38.  
39.     if (SystemInfo.supportsGyroscope == true) {
40.         Input.gyro.enabled = true;                // if we have a gyro, enable the gryo
41.         Input.gyro.updateInterval = 0.001;         // sets the sensitivity of the gyro
42.         //GyroRotation = Input.gyro.rotationRateUnbiased; //- GyroOffset.y;
43.         //GyroAttitude = Input.gyro.attitude;
44.         //MovementScript = Player.GetComponent(AirplaneMovement);
45.     }
46. }
47.  
48. function FixedUpdate () {
49.  
50.     GyroAttitude = Input.gyro.attitude;
51.  
52.  
53.     /*
54.     // =================== START - temporary code to help me understand the Gyro output
55.     GyroRotation = Input.gyro.rotationRateUnbiased;
56.  
57.     if (Input.gyro.rotationRateUnbiased.x > MaxRotationRate) MaxRotationRate = GyroRotation.x;
58.     if (Input.gyro.rotationRateUnbiased.x < MinRotationRate) MinRotationRate = GyroRotation.x;
59.  
60.     print("Raw Gyro Attitude X: " + GyroAttitude.x + " RotationRateUnbiased: " + GyroRotation.x + " Max Rotation Rate: "
61.             + MaxRotationRate + " Min Rotation Rate: " + MinRotationRate);
62.  
63.     // =================== END - this is temporary code to help me understand the Gyro output
64.     */
65.  
66.     if (GyroAttitude.y > GyroYDeadNeg && GyroAttitude.y < GyroYDeadPos) {
67.         Player.GetComponent(AirplaneMovement).ResetAirplane();
68.         }
69.  
70.     else if (GyroAttitude.y < GyroBarrelRollPos && GyroAttitude.y > GyroBarrelRollNeg) {
71.         Player.GetComponent(AirplaneMovement).BankAirplane(GyroAttitude.y);
72.         }
73.  
74.     else if (GyroAttitude.y > GyroBarrelRollPos || GyroAttitude.y < GyroBarrelRollNeg) {
75.         Player.GetComponent(AirplaneMovement).DoBarrelRoll(-GyroAttitude.y);
76.      
77.     }
78.  
79.  
80.     //Test the "forward tilt" of the device
81.  
82.     if (GyroAttitude.x > GyroXDeadNeg && GyroAttitude.x < GyroXDeadPos){
83.         //perform camera creep to catchup to plane's speed
84.     }
85.  
86.     else if (GyroAttitude.x < GyroXDeadNeg) {
87.         //tilted away from user - increase power
88.         Player.GetComponent(AirplaneMovement).PowerIncrease();
89.     }
90.  
91.     else if (GyroAttitude.x > GyroXDeadPos) {
92.         //tilted towards user - decrease power
93.         Player.GetComponent(AirplaneMovement).PowerDecrease();
94.     }
95.      
96.  
97.  
98. }

TouchInput.js

Code (JavaScript):

1.  
2. #pragmastrict
3.  
4. varPlayer : GameObject; //Thisisfortheplayer'sairplane
5.  
6. //tuningvariables
7. varSwipeRightThreshold : float = -100; //minimumleft-swipedistance
8. varSwipeLeftThreshold : float = 100; //minimumright-swipedistance
9. varSwipeUpThreshold : float = 100; //minimumup-swipedistance
10. varSwipeDownThreshold : float = -100; //minimumdown-swipedistance
11.  
12. privatevarfirstPosition = newVector2[10];
13. privatevarlastPosition = newVector2[10];
14.  
15. privatevarCurrentTouch : Touch;
16.  
17.  
18. functionStart () {
19.  
20.  
21. }
22.  
23. functionUpdate () {
24.  
25. //startbycheckingiftouchesexist
26.  
27. if (Input.touchCount > 0) {
28.  
29. //foreachtouchesthatexists
30. for (vartouch: TouchinInput.touches){
31.  
32. //CurrentTouch = Input.GetTouch[touch];
33.  
34. if (touch.phase == TouchPhase.Began) {
35. firstPosition[touch.fingerId] = touch.position;
36. lastPosition[touch.fingerId] = touch.position;
37. print("TouchStarted - index: " + touch.fingerId);
38. }
39.  
40. if (touch.phase == TouchPhase.Moved) {
41. lastPosition[touch.fingerId] = touch.position;
42. print("TouchMoved - index: " + touch.fingerId);
43.  
44. }
45.  
46. if (touch.phase == TouchPhase.Stationary);
47.  
48. if (touch.phase == TouchPhase.Ended) {
49. print("TouchEnded - index: " + touch.fingerId);
50.  
51. //thisblockdeterminesifdudeswiped
52.  
53. if ((firstPosition[touch.fingerId].x - lastPosition[touch.fingerId].x) > SwipeLeftThreshold) {
54. //dudeswipedright - triggeryourrightswipemoves
55. //thishasbeengivenovertoweaponchange "back"
56.  
57. print(" ##### swipeleft #####");
58. //print(firstPosition[touch.fingerId].x - lastPosition[touch.fingerId].x);
59.  
60. Player.GetComponent(WeaponsControl).changeWeapon(-1);
61.  
62. }
63.  
64. elseif ((firstPosition[touch.fingerId].x - lastPosition[touch.fingerId].x) < SwipeRightThreshold) {
65. //dudeswipedleft - triggerleftswipemoves
66. //thishasbeengivenovertoweaponchange "forward"
67. print(" ##### swiperight #####");
68. //print(firstPosition[touch.fingerId].x - lastPosition[touch.fingerId].x);
69.  
70. Player.GetComponent(WeaponsControl).changeWeapon(1);
71. }
72.  
73. elseif ((lastPosition[touch.fingerId].y - firstPosition[touch.fingerId].y )> SwipeUpThreshold) {
74. //dudeswipedup - triggerupswipeupmove
75. print(" ##### swipeup #####");
76. Player.GetComponent(AirplaneMovement).CommenceLoopTheLoop(true);
77.  
78. }
79.  
80. elseif ((lastPosition[touch.fingerId].y - firstPosition[touch.fingerId].y )< SwipeDownThreshold) {
81. //dudeswipeddown - triggerswipedownmove
82. print(" ##### swipedown #####");
83. Player.GetComponent(AirplaneMovement).CommenceLoopTheLoop(false);
84.  
85.  
86. }
87.  
88.  
89.  
90. else {
91. //ifdudedidn'tswipe, thendudetapped
92. //thisisgivenoverto 'firecurrentlyequippedweapon'
93.  
94. print(" ##### TAPPED ##### ");
95. Player.GetComponent(WeaponsControl).fireWeapon();
96.  
97.  
98.  
99. }
100.  
101.  
102.  
103.  
104. //Afteratouchisended, itiscanceled (removedfromthetoucharray) - usethiszerooutoriginalposition
105.  
106. if (touch.phase == TouchPhase.Canceled){
107. print("TouchCanceled - index: " + touch.fingerId);
108. firstPosition[touch.fingerId] = Vector2(0,0);
109. lastPosition[touch.fingerId] = Vector2(0,0);
110.  
111. }
112.  
113. }
114.  
115.  
116. }
117.  
118.  
119. }
120.  
121.  
122. }

Create yourself an object, put the camera above it, looking 'top down' so that "forward" is Z and "left/right" is X.

Replicate the error by swiping forward to trigger a 'loop-the-loop', then when the manoeuvre completes, gyro in any direction. You will see what I mean on device and in editor.

(Test Hardware - iPad 4, iPhone 5s, iPhone 4).

 

I have confirmation this is happening independently of my equipment (built my project on a friend's laptop)

 

Big shout out to AdamW who found my n00bish error!

Code (JavaScript):

1. transform.Translate(SpeedMultiplierBank * Time.deltaTime, PositionY, PositionZ, Space.World);

will move not to "positionY, PositionZ" but will add transform.position.y to the current transform.position.y every frame when the plane was moving - causing the run away game object.

It should be transform.Translate(how much to change X by, how much to change Y by, how much to change Z by, what space to do it in).