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Moving and scaling an object according to hand position

I need some help with my college project. I have a cylinder and need it to act as a coil. For example, if I touched the cylinder's surface it's height will decrease (scaled in the y direction) as if pressing on a coil then when I remove my hand it returns back to its original size.
This is what I reached till now but I still have some problems that I can't solve.
public class Deformation : MonoBehaviour
{
Vector3 tempPos;
private void InteractionManager_SourceUpdated(InteractionSourceUpdatedEventArgs hand)
{
if (hand.state.source.kind == InteractionSourceKind.Hand)
{
Vector3 handPosition;
hand.state.sourcePose.TryGetPosition(out handPosition);
float negXRange = transform.position.x - transform.localScale.x;
float posXRange = transform.position.x + transform.localScale.x;
float negYRange = transform.position.y - (transform.localScale.y / 2);
float posYRange = transform.position.y + (transform.localScale.y / 2);
float negZRange = transform.position.z - transform.localScale.z;
float posZRange = transform.position.z + transform.localScale.z;
float handX = handPosition.x;
float handY = handPosition.y;
float handZ = handPosition.z;
if ((negXRange <= handX) && (handX <= posXRange) && (negYRange <= handY) && (handY <= posYRange) && (negZRange <= handZ) && (handZ <= posZRange))
{
tempPos.y = handPosition.y;
transform.localScale = tempPos;
}
else
{
tempPos.y = 0.3f;
transform.localScale = tempPos;
}
}
}
// Use this for initialization
void Start()
{
tempPos = transform.localScale;
InteractionManager.InteractionSourceUpdated += InteractionManager_SourceUpdated;
}
I attached two scripts to my object (cylinder) the TapToPlace script from the HoloToolKit and the deformation script stated above. The problem is when I deploy to my HoloLens to test, when I place the cylinder first to the needed place then try to deform it after that, it is placed but not deformed. If I tried it the other way around both work. Any ideas why does the deformation script does not work after the TapToPlace one?
The cylinder when viewed by my HoloLens is somehow transparent. I mean that I can see my hand through it. I need it to be more solid.
I wonder if there is something like a delay that I can use because when I use the deformation script stated above the cylinder is scaled to my hand position then scaled back to its default size very fast and appears as if blinking.
At first I place the cylinder on a setup (something as a table for example) then I begin to deform it. When I commented the else part in the deformation script stated above, it was scaled and left stable without returning to the original size. It is scaled symmetrically so its height is decreased from up and down resulting in the base of the cylinder becomes away from the table. I need the base of the cylinder to be always stable and touching the table under it.
Note: I am using Unity 2017.3.1f1 (64-bit) - HoloToolkit-Unity-2017.2.1.3
Thank you in advance.

1) Did you see the MRTK 2017.2.1.4 release? It has some useful features such as two handed resizing/scaling of objects. The BoundingBox code in the new MRTK release does moving and resizing in one component, it might be a better base to start from than the TapToPlace, or at least show how the two types of transform can work together.
2) What colour is your object? Hololens will render black as transparent, so try making the object bright white for testing. Also, just double check the brightness is turned up to full (the LHS buttons on the hololens). Finally, check your shader is the MRTK Standard shader. (again, the 2017.2.1.4 release has new shader code you might want to try.) . In a room without direct sunlight it should pretty much cover up your hand.
4) I'm not sure I follow completely, but the pivot point could be important here. If it is centred in the middle of the coil (as I'd imagine it is) then when you deform the coil down it will still stay centered at that central pivot point.
If you instead set the pivot point to the bottom of the coil, touching the table, you can scale and that point stays on the table and the top does all the moving.

unity Rotate between min and max distance

I'm trying to make it possible to drag an object. This object can only rotate so much. (Similair to a door).
Here is the code abit edited that rotates an object which works.
I have 2 vectors for maxrotation and minrotation.
This code will be called whenever the user is dragging the interactible object. (like update but only when dragged)
if (GestureManager.Instance.IsNavigating &&
HandsManager.Instance.FocusedGameObject == gameObject)
{
//speed and navigiation of rotation
float rotationFactor;
rotationFactor = ManipulationManager.Instance.ManipulationPosition.y * RotationSensitivity;
totransform.Rotate(new Vector3(rotationFactor, 0, 0));
}
It would be great if I could use an if statement here. And I tried quite some things but it's still not working.
As stated the code paste here works. The object should be dragable but only up to a certain points.
totransform is the transform that will be rotated
Any ideas would be great and most appreciated.
Kind regards.

I think you want to look at eulerAngles. Check the values you're getting then set an if-statement before doing the rotation. This is a sample code for you to find the values you want:
if (GestureManager.Instance.IsNavigating &&
HandsManager.Instance.FocusedGameObject == gameObject)
{
//speed and navigiation of rotation
float rotationFactor = ManipulationManager.Instance.ManipulationPosition.y * RotationSensitivity;
Debug.Log(totransform.eulerAngles);
if (totransform.eulerAngles.x < 100) {
totransform.Rotate(new Vector3(rotationFactor, 0, 0));
}
}

So here is the solution that worked for me. First I declare the movement variable (not seen down below, which is 2 in this case). Then I track the distance covered and put a limit on that.
Of course there are some improvements to this code like use movement instead of 2. But because of time constraints I didn't do it.
if (GestureManager.Instance.IsNavigating &&
HandsManager.Instance.FocusedGameObject == gameObject)
{
//here we get the movement direction and set it in movement.
if (GestureManager.Instance.NavigationPosition.y > 0)
{
movement = 2;
}
else if (GestureManager.Instance.NavigationPosition.y < 0)
{
movement = -2;
}
//the first part is false if we reach higher then maxdistance and the movement is going up
//the second part is false if we reach the lower distance and the movement is going down.
if ((!(distance > maxdistance.x) || movement < 0) && ((!(distance < mindistance.x) || movement > 0)))
{
//here we add the movement to the distance so we know if it gets closer or further
distance += movement;
//here we rotate
totransform.Rotate(new Vector3(movement, 0, 0));
}
}

How do I make character play another animation when moving left?

I have script which makes character (gameobject) move right.
How do I make so when he reaches right border, and character starts moving left with playing another animation (moving left)?
Here is my script of character's moving right and left
void MovementRight()
{
_character.transform.Translate (Vector2.right 100f Time.deltaTime);
}
void MovementLeft()
{
_character.transform.Translate (Vector3.left 100f Time.deltaTime);
}

I would suggest you handle animations with Animator, and make the horizontal animation to be handled by a float variable in Animator, (so when it is -1 animate walking left, and 1 animate walking right).
So you will need to make 3 scripts.
//This will handle the animator getting the speed of the character from MovingHandler
AnimationHandler.cs
//This will actually move the character based on input handler
MovingHandler.cs
//Here you will hear to inputs
InputHandler.cs
And to make suere the character won't move outside the screen you will need to get the screenbounds on MovingHandler and make a check before moving the character, if it is in the same spot in x as the bounds of the screen you will make a return; also if it is going to the left and the character is <= than left bound then return; and the same on the right bound >= then return;
Something like this:
Transform charTransform;
float leftHorizontalBound;
float rightHorizontalBound;
void Start()
{
charTransform = this.transform;
leftHorizontalBound = camera.ViewportToWorldPoint (new Vector3 (0,0, camera.nearClipPlane)).x;
rightHorizontalBound= camera.ViewportToWorldPoint (new Vector3 (1,0, camera.nearClipPlane)).x;
}
void Update()
{
if(charTransform.position.x <= leftHorizontalBound)
{
charTransform.position = new vector2(leftHorizontalBound + 0.1f);
return;
}
if(charTransform.position.x >= rightHorizontalBound)
{
charTransform.position = new vector2(rightHorizontalBound - 0.1f);
return;
}
//MAKE HERE YOUR MOVEMENT BASED ON INPUT.
}
Dont use that code just use the idea, since i didn't test it, i just code it here.
I hope it helped.

Jump animation using animation class

I need a little help in my little 2D game I want to create in XNA. I had almost no knowledge of programming before I got interested in XNA and C#, so maybe my problem is simple, but I just can't figure it out.
So basically, I have a base class, and I created an additional class Animation for animating sprites. I implemented some methods so that when the player presses "right" it would change the animation's current texture and increment X by a number of xf; anyway, the main idea is that I'm using just one instance of my class (basically, one object of type animation which changes its texture and properties based on what key is pressed).
So, I had no problems making it run right or left. Works out pretty well. The big problem started when I wanted to implement the jump sprite. So I created the 6 frames necessary for the sprite, but to animate it I have virtually no idea how to do it.
The only thing it does right now is to loop through the frames of the sprite, but the position (both .X and .Y) remain the same. The thing is, I have a Vector2 position which holds the animation's current position, and it's fine with running because I simply increment it. However, when it comes to jumping, I want it to increment .X, but the .Y should be decremented (thus going up) until frame number 3; after frame number 3, until the last frame, I want the .Y position to go down (thus fall) with the corresponding animations (erm, frames).
So, basically, I don't know how to modify the .X and .Y so that it would display the frames that I need in the time I need. I don't know if you really understood what I'm trying to say; basically when I press the "up" key, it loops through the frames but the position remains the same.
My idea was to use a reference to the actual Vector2 position which holds the animation's current position and pass it to the method in the other Animation.cs class, namely the PlayAnimJump, and modify the position after each frame and return it to the actual Game1.cs by reference. Even if I would do that (though I fail to see what good it would be), it wouldn't be updating the position as it should. So, any ideas?
Here is the code for the PlayAnimJump method from the Animation class:
public void PlayAnimJump(GameTime gameTime)
{
elapsed += (float)gameTime.ElapsedGameTime.Seconds;
sourceRect = new Rectangle(currentFrame * frameWidth, 0, frameWidth, frameHeight);
currentFrame = 0;
if (elapsed >= frameTime)
{
if (currentFrame <=3)
{
if (looping)
{
currentFrame++;
}
}
else if (currentFrame > 3)
{
currentFrame++;
}
elapsed = 0;
}
}
The default constructor for that class:
public Animation(ContentManager Content,string asset,float frameSpeed, int numbOfFrames, bool looping,Vector2 positionIT)
{
this.assetName = asset;
this.frameTime = frameSpeed;
this.numbOfFrames = numbOfFrames;
this.looping = looping;
this.animation = Content.Load<Texture2D>(asset);
frameWidth=(animation.Width / numbOfFrames);
frameHeight=animation.Height;
position = positionIT;
}
Here is the code (from the main) when the up key is pressed:
else if (up)
{
check = animation1.GetAsset();
if (check == "eright")
{
animation1.SetFrameSpeed(0.8f);
animation1.SetNumbOfFrames(6);
animation1.ChangeTexture(Content, "SarimCumVreJiorjica");
animation1.PlayAnimJump(gameTime);
/*position1.x +=2f;
position1.Y -=2f;
*/
}
So, I'm not sure how, but I'm supposed to change position1 according to the frame that's displayed by the animation in that second. Am I missing something?

If your animation class had a reference to the object that you wanted to move (i.e the object holding the position field) then you could modify it within the animation class, within the PlayAnimJump method.
Or, to reduce coupling, you could just have PlayAnimJump return a variable indicating how far into the jump you are (maybe a percentage of the jump, from 0 to 1). Then, you could use the percentage outside to set the objects position. So, if the jump is halfway done, the return value would be 0.5f, which you could use in an equation to determine the players y position. An example equation would be:
float percent = animation1.PlayAnimJump(gameTime);
float y = Math.Sin(percent * Math.PI) * maxJumpHeight;
player.positon.y = y;
This uses a sine wave to determine the players height throughout the jump animation. You would just need to write the code that determines the percentage of the way through the jump (currentFrame) in the PlayAnimJump method and return it.

Formula of the frуefall for Y coordinate is
y = g * t ^ 2 / 2 + v0 * t + y0
Characters jump from height y0 vith start velocity v0 by Y axis and gravity gradually slows down and starts to fall.
Calculate deltaY using following formula
deltaY = g * t ^ 2 / 2 + v0 * t
First show the frame on which the character is pushed off the ground, then the frame on which it rises until it reaches the peak of the jump. Once the sign change deltaY from + to - show how the character change pose for fall. Something like that.

Calculating/Predicting a way

I'm just starting with physics, so I'm not always sure about what I'm doing. It's a 2D project but I'm using 3D physical objects like SphereCollider etc..
What I have:
Objects floating in space and affecting each other through gravity:
protected virtual IEnumerator OnTriggerStay(Collider other) {
yield return new WaitForFixedUpdate();
if(other.attachedRigidbody) {
Vector3 offsetVector = this.transform.position - other.transform.position;
float distance = offsetVector.magnitude;
float gravityForce = (other.rigidbody.mass * mass) / Mathf.Pow(distance, 2);
// Clamp gravity.
if(gravityForce > 1.0F) {
gravityForce = 1.0F;
}
other.attachedRigidbody.constantForce.force = offsetVector.normalized * gravityForce;
}
}
There are controllable objects on which the player can click and drag a line away from the object in order to give it a force (shoot) in the opposite direction.
What I want to achieve:
The player should see a rough prediction of the way while aiming. That means that the way-prediction needs to take in account the current velocity, the force which would be applied when the player release the mouse button and the gravity of the surrounding objects.
What I have tried so far:
For testing purposes I just save the computed/predicted positions in an array and draw those positions in OnDrawGizmos().
I wrote a method which returns the gravity influence for a certain position called computeGravityForPosition(Vector3 position).
And thats how I try to calculate the positions:
private void drawWayPrediction() {
Vector3 pos = this.transform.position;
// The offsetVector for the shooting action.
Vector3 forceVector = pos - Camera.main.ScreenToWorldPoint(Input.mousePosition);
forceVector.z = 0.0F;
// The predicted momentum scaled up to increase the strength.
Vector3 force = (forceVector.normalized * forceVector.magnitude);
// 1. I guess that this is wrong, but don't know how to do it properly.
momentum = this.rigidbody.velocity + force;
for(int i = 0; i < predictionPoints.Length; i++) {
float t = i * Time.fixedDeltaTime;
momentum += computeGravityForPosition(pos);
pos += momentum * t * t;
predictionPoints[i] = pos;
}
}
At the beginning, when the objects just slowly approaching each other it looks okay. After the first shot, the prediction is completely wrong. I guess it is because of 1. in the code. Just adding the force to the velocity is probably horrible wrong.
Thank you very much for your time.
EDIT:
I removed seemingly unnessecary parts.
I still think that the main problem lays in 1. in the code. I just don't know how to mix up the current movement of the object (from which I only have the current velocity as far as I know the physics engine of unity) with the new created force:
Vector3 forceVector = pos - Camera.main.ScreenToWorldPoint(Input.mousePosition);
Vector3 force = (forceVector.normalized * forceVector.magnitude);

So if you are using a new version of unity probably above 2018, you can use the nice method
Physics.Simulate(dt); // delta time, dt, is the amount of time to simulate.
https://docs.unity3d.com/ScriptReference/Physics.Simulate.html
https://docs.unity3d.com/2018.3/Documentation/ScriptReference/PhysicsScene.Simulate.html
By using this function you can manually advance the simulation.
This method should be applied to a different physics scene.
Therefore I suggest that when you click you will simulate a few physics steps (the more you will simulate the more accurate indication the player will get),
with every step you store the position of the object and when you are done simulating draw a line between all the points.
In my opinion, it should run quite fast if done correctly.
The code should look something like this:
public PhysicsScene physicsScene;
GameObject actualBall;
GameObject simulatedBall;
OnClick() {
simulatedBall.SetPosition(actualBall.transform.position);
if (!physicsScene.IsValid())
return; // do nothing if the physics Scene is not valid.
for (int i=0; i < 10; i++) {
physicsScene.Simulate(Time.fixedDeltaTime);
// store the position.
myPoints.append(simulatedBall.rb.position);
}
// draw a line from the stored points.
}
In addition there is this video that I hope will help, good luck
https://www.youtube.com/watch?v=GLu1T5Y2SSc
I hope I answered your question and if not tell me :)

Disclaimer : Unfortunately I suck at math so can't provide any code for the calculations.
Now that the legal stuff is out of the way :)
In my opinion you are looking at this all wrong. What you need is to calculate the curve (path of the objects trajectory) and then simply plot the curve in OnDrawGizmos with a line renderer.
You don't need to simulate the behaviour of the object. Not only is this a LOT faster but it's also simpler in terms of TimeScale shenanigans. By changing the TimeScale you are also affecting the TimeScale of your trajectory simulation which will most likely look and feel weird.
By doing a basic trajectory calculation you will not have this issue.
PS: This link might help.