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How can I set the newPositions distance to be shorter closer to the original squadMembers positions?

I have 3 formations:
In each formation I'm calculating new positions to move to and add them to the List newPositions.
private void FormationTriangle()
{
newpositions = new List<Vector3>();
int height = Mathf.CeilToInt((Mathf.Sqrt(8 * squadMembers.Count + 1f) - 1f) / 2);
int slots = (int)(height * (height + 1f) / 2f);
float verticalModifier = 1.25f; // * 1.25f to increase horizontal space
float horizontalModifier = 0.8f; // * 0.8f to decrease "vertical" space
float width = 0.5f * (height - 1f);
Vector3 startPos = new Vector3(width * horizontalModifier, 0f, (float)(height - 1f) * verticalModifier);
int finalRowCount = height - slots + squadMembers.Count;
for (int rowNum = 0; rowNum < height && newpositions.Count < squadMembers.Count; rowNum++)
{
for (int i = 0; i < rowNum + 1 && newpositions.Count < squadMembers.Count; i++)
{
float xOffset = 0f;
if (rowNum + 1 == height)
{
// If we're in the last row, stretch it ...
if (finalRowCount != 1)
{
// Unless there's only one item in the last row.
// If that's the case, leave it centered.
xOffset = Mathf.Lerp(
rowNum / 2f,
-rowNum / 2f,
i / (finalRowCount - 1f)
) * horizontalModifier;
}
}
else
{
xOffset = (i - rowNum / 2f) * horizontalModifier;
}
float yOffset = (float)rowNum * verticalModifier;
Vector3 position = new Vector3(
startPos.x + xOffset, 0f, startPos.y - yOffset);
newpositions.Add(position);
}
}
move = true;
formation = Formation.Square;
}
private Vector3 FormationSquarePositionCalculation(int index) // call this func for all your objects
{
float posX = (index % columns) * gaps;
float posY = (index / columns) * gaps;
return new Vector3(posX, posY);
}
private void FormationSquare()
{
newpositions = new List<Vector3>();
quaternions = new List<Quaternion>();
for (int i = 0; i < squadMembers.Count; i++)
{
Vector3 pos = FormationSquarePositionCalculation(i);
//squadMembers[i].transform.position = new Vector3(transform.position.x + pos.x, 0, transform.position.y + pos.y);
squadMembers[i].transform.Rotate(new Vector3(0, -90, 0));
newpositions.Add(new Vector3(transform.position.x + pos.x, 0, transform.position.y + pos.y));
}
move = true;
squareFormation = true;
formation = Formation.Circle;
}
private Vector3 FormationCirclePositionCalculation(Vector3 center, float radius, int index, float angleIncrement)
{
float ang = index * angleIncrement;
Vector3 pos;
pos.x = center.x + radius * Mathf.Sin(ang * Mathf.Deg2Rad);
pos.z = center.z + radius * Mathf.Cos(ang * Mathf.Deg2Rad);
pos.y = center.y;
return pos;
}
private void FormationCircle()
{
newpositions = new List<Vector3>();
quaternions = new List<Quaternion>();
Vector3 center = transform.position;
float radius = (float)circleRadius / 2;
float angleIncrement = 360 / (float)numberOfSquadMembers;
for (int i = 0; i < numberOfSquadMembers; i++)
{
Vector3 pos = FormationCirclePositionCalculation(center, radius, i, angleIncrement);
var rot = Quaternion.LookRotation(center - pos);
if (Terrain.activeTerrain == true)
pos.y = Terrain.activeTerrain.SampleHeight(pos);
pos.y = pos.y + yOffset;
newpositions.Add(pos);
quaternions.Add(rot);
}
move = true;
squareFormation = false;
formation = Formation.Triangle;
}
Then I'm moving the squadMembers to the newPositions:
private void MoveToNextFormation()
{
if (randomSpeed == false)
{
if (step.Length > 0)
step[0] = moveSpeed * Time.deltaTime;
}
for (int i = 0; i < squadMembers.Count; i++)
{
squadMembers[i].transform.LookAt(newpositions[i]);
if (Vector3.Distance(squadMembers[i].transform.position, newpositions[i]) > 30f)
{
if (randomSpeed == true)
{
squadMembers[i].transform.position =
Vector3.MoveTowards(squadMembers[i].transform.position, newpositions[i], step[i]);
}
else
{
squadMembers[i].transform.position =
Vector3.MoveTowards(squadMembers[i].transform.position, newpositions[i], step[0]);
}
}
if (Vector3.Distance(squadMembers[i].transform.position, newpositions[i]) < threshold)
{
if (squareFormation == true)
{
Vector3 degrees = new Vector3(0, 0, 0);
Quaternion quaternion = Quaternion.Euler(degrees);
squadMembers[i].transform.rotation = Quaternion.Slerp(squadMembers[i].transform.rotation, quaternion, rotateSpeed * Time.deltaTime);
}
else
{
squadMembers[i].transform.rotation = Quaternion.Slerp(squadMembers[i].transform.rotation, quaternions[i], rotateSpeed * Time.deltaTime);
}
}
}
}
But if I want that the squadMembers will not move at all but will change to the next formation on the same position they are ? Or maybe to move just a little bit for example to distance 20 or 5 or 30 or 300 ?
I tried to add a distance check for the move:
if (Vector3.Distance(squadMembers[i].transform.position, newpositions[i]) > 30f)
So they are changing to the next formation when the distance more then 30.
But then the formation is not looking good. If for example it's the square formation the formation after they finished moving looks like a wave.
Screenshot example:
Wave formation

Unity: Knockback my player along the Y-axis

I don't think the Y-axis for my code is working. Iv'e tried increasing the yForceToAdd and the localScale.y but (when I collide with the object that has this script attached to it) my player only goes (when I collide at the top of the object) X=1, Y=1 or X=-1, Y=1 and not X=0, Y=1 as well. the same problem with the bottom of my object X=0, Y=-1 doesn't seem to work either. can someone help with this problem?
public float xForceToAdd;
public float yForceToAdd;
void OnTriggerEnter2D(Collider2D other) {
if (other.gameObject.tag == "Player")
{
//Store the vector 2 of the location where the initial hit happened;
Vector2 initialHitPoint = new Vector2(other.gameObject.transform.position.x, other.gameObject.transform.position.y);
float xForce = 0;
float yForce = 0;
//Grab our collided with objects rigibody
Rigidbody2D rigidForForce = other.gameObject.GetComponent < Rigidbody2D > ();
//Determine left right center of X hit
if (initialHitPoint.x > (this.transform.position.x + (this.transform.localScale.x / 3)))
{
xForce = 1;
}
else if (initialHitPoint.x < (this.transform.position.x - (this.transform.localScale.x / 3)))
{
xForce = -1;
}
else
{
xForce = 0;
}
if (initialHitPoint.y > (this.transform.position.y + (this.transform.localScale.y / 3)))
{
yForce = 1;
}
else if (initialHitPoint.y < (this.transform.position.y - (this.transform.localScale.y / 3)))
{
yForce = -1;
}
else
{
yForce = 0;
}
rigidForForce.velocity = new Vector2(xForce * xForceToAdd, yForce * yForceToAdd);
}
}

The logic in computing the margins where the hit is being registered is wrong. For example in this.transform.localScale.y / 3, the localScale.y with probably give you 1.0f, but what you meant inside the expression (this.transform.position.y + (this.transform.localScale.y / 3) is that you want the y-center of the object, plus one-third of it's height. However, this.transform.localScale.y will only give you a "multiplier" so to say. In a unscaled object, transfomr.localScale will be 1.0, so you would be adding transform.position.y + (1.0f / 3), which is probably not what you want. You must multipliy this with the actual height of the object to get what you want. This can be done by either relying on the Sprite or a Collider, e.g. a BoxCollider2D. Modified logic (I also divided by 3f instead of by 3 to make it a more accurate floating point division..):
public float xForceToAdd;
public float yForceToAdd;
void OnTriggerEnter2D(Collider2D other) {
if (other.gameObject.tag == "Player")
{
//Store the vector 2 of the location where the initial hit happened;
Vector2 initialHitPoint = new Vector2(other.gameObject.transform.position.x, other.gameObject.transform.position.y);
float xForce = 0;
float yForce = 0;
//Grab our collided with objects rigibody
Rigidbody2D rigidForForce = other.gameObject.GetComponent < Rigidbody2D > ();
//Get the width and height of this object by looking up the size of the box collider
//Alternatively, use constant values here or rely on the Sprite.
float width = GetComponent<BoxCollider2D>().size.x;
float height = GetComponent<BoxCollider2D>().size.y;
//Determine left right center of X hit
if (initialHitPoint.x > (this.transform.position.x + width * (this.transform.localScale.x / 3f)))
xForce = 1;
else if (initialHitPoint.x < (this.transform.position.x - width* (this.transform.localScale.x / 3f)))
xForce = -1;
else
xForce = 0;
if (initialHitPoint.y > (this.transform.position.y + height * (this.transform.localScale.y / 3f)))
yForce = 1;
else if (initialHitPoint.y < (this.transform.position.y - height * (this.transform.localScale.y / 3f)))
yForce = -1;
else
yForce = 0;
Debug.Log(string.Format("Hit Point X: {0}. Left Boundary: {1} Right Boundary: {2}, xForce = {3}", initialHitPoint.x, (this.transform.position.x - width*this.transform.localScale.x / 3f), (this.transform.position.x + width * (this.transform.localScale.x / 3f)), xForce));
rigidForForce.velocity = new Vector2(xForce * xForceToAdd, yForce * yForceToAdd);
}
}

Rotating a circle with mouse with direction

I am rotating a circle with a mouse but I want there to be a limit on how far the circle can be rotated. (Lets say 3 full times). When it reaches it's limit it can no longer be turned in that same direction, but the opposite direction it can be. I got it stopping after the max turns but now I'm trying to find the direction and every time my mouse passes the x-axis of the circle the direction changes because atan2 gives me the angle relative to the x-axis. So the new mouse position is in one quadrant and the last position is in another quadrant so subtracting these angles doesn't give me what I want. Did I explain this well? Any suggestions?
private void HelmPb_MouseMove(object sender, MouseEventArgs e)
{
if ((e.Button != MouseButtons.Left) || _dontTurn) return;
double angle = OffsetAngle();
Point temp = MousePosition;
float degrees = Convert.ToSingle(angle - _offsetAngle);
float diff = _lastHelmAngle - degrees;
float absDiff = Math.Abs(diff) % 360;
if (absDiff > 180) absDiff = 360 - absDiff;
double angle1 = Math.Atan2(_lastHelmPoint.Y, _lastHelmPoint.X);
if (angle1 < 0) angle1 += 2*Math.PI;
double angle2 = Math.Atan2(temp.Y, temp.X);
if (angle2 < 0) angle2 += 2*Math.PI;
double direction = angle1 - angle2;
direction = direction*(180/Math.PI);
_deltaHelmTurn += Convert.ToSingle(absDiff);
if (_deltaHelmTurn >= (_maxHelmTurn*360.0))
{
if (direction > 0 && _lastHelmDirection > 0)
{
_deltaHelmTurn = Convert.ToSingle(_maxHelmTurn*360.0);
degrees = Convert.ToSingle(_maxHelmTurn*360.0)%360;
}
}
_lastHelmDirection = direction;
_lastHelmPoint = MousePosition;
_lastHelmAngle = Convert.ToSingle(degrees);
_sameHelmRotation = Convert.ToSingle(degrees);
HelmPb.Image.Dispose();
WaterDepthPlot.Update();
HelmPb.Image = RotateImage(_originalHelmImage, -degrees);
HelmPb.Update();
}
private double OffsetAngle()
{
int helmXMid = HelmPb.PointToScreen(Point.Empty).X + (HelmPb.Width / 2);
int helmYMid = HelmPb.PointToScreen(Point.Empty).Y + (HelmPb.Height / 2);
double angle = AngleFromPoints(MousePosition, new Point(helmXMid, helmYMid));
return angle;
}
private double AngleFromPoints(Point pt1, Point pt2)
{
Point p = new Point(pt1.X - pt2.X, pt1.Y - pt2.Y);
double alpha;
if (p.Y == 0) alpha = p.X > 0 ? 0d : 180d;
else
{
double f = 1d * p.X / (Math.Sqrt(p.X * p.X + p.Y * p.Y));
alpha = Math.Acos(f) * 180d / Math.PI;
if (p.Y > 0) alpha = 360d - alpha;
}
return alpha;
}

The direction of rotation between two vectors is equivalent to the sign of their cross product.
//Returns 1 for CCW, -1 for CW, 0 for no change
private int Direction(Point from, Point to)
{
double cross = (from.x * to.y) - (from.y * to.x);
return Math.Sign(cross);
}

Doom-like angle based sprite changing

So, i'm trying to make a first person game that used the same sprite mechanics as games like Doom, Duke Nukem and etc.
So far, i can identify the angle I'm at in relation to static objects, but not to rotating ones. I have some "enemies" that change rotation and start following me, but calculating the tangent angle (Mathf.Atan2) doesn't take the enemy's rotation in consideration.
Here's the code i'm using so far, which works perfectly for objects that dont rotate:
int GetAngleIndex()
{
var dir = cam.transform.position - transform.parent.forward;
var enemyAngle = Mathf.Atan2(dir.z, dir.x) * Mathf.Rad2Deg;
if (enemyAngle < 0.0f)
enemyAngle += 360;
Debug.Log("Angle from the player is: " + enemyAngle);
if (enemyAngle >= 292.5f && enemyAngle < 337.5f)
return 8;
else if (enemyAngle >= 22.5f && enemyAngle < 67.5f)
return 2;
else if (enemyAngle >= 67.5f && enemyAngle < 112.5f)
return 3;
else if (enemyAngle >= 112.5f && enemyAngle < 157.5f)
return 4;
else if (enemyAngle >= 157.5f && enemyAngle < 202.5f)
return 5;
else if (enemyAngle >= 202.5f && enemyAngle < 247.5f)
return 6;
else if (enemyAngle >= 247.5f && enemyAngle < 292.5f)
return 7;
else if (enemyAngle >= 337.5f || enemyAngle < 22.5f)
return 1;
else return 0;
}
I've searched for hours and I can't find a solution to this :(

You say your [only] problem is that it doesn't take their rotation into account - I'm guessing that means that you're not having trouble billboarding your sprites, and your rotation works when they're facing forward. To that end:
The dot product of vectors a and b is equal to cos(theta)*magnitude(a)*magnitude(b). So if a is the vector from the camera to the object:
var a = cam.transform.position - transform.parent.position
and b is the object's forward:
var b = transform.parent.forward
and we know that a and b both have magnitude 1
a.Normalize();
//b is already normalized
then we know that this is equal to cos(theta), where theta is the angle between them.
var theta = Mathf.Acos(Vector3.Dot(a, b)) * Mathf.Rad2Deg;
However. Theta is the shortest necessary angle - so it will be from 0 to 180. Given your switch table up there, we know that when we're hoping to go around the wrong way, we'll be in the wrong position. so to fix that:
if (a.x * a.z < 0)
theta = 360.0f - theta;
then we just plug it in and go. Here's the full file in my project:
using UnityEngine;
public class spriteAngler : MonoBehaviour
{
public Transform toFace;
public SpriteRenderer toManipulate;
public Sprite[] mySprites;
private float theta;
private Vector3 a;
void Update()
{
toManipulate.sprite = mySprites[GetAngleIndex()];
}
int GetAngleIndex()
{
a = toFace.position - transform.position;
a.Normalize();
var b = transform.forward;
theta = Mathf.Acos(Vector3.Dot(a, b)) * Mathf.Rad2Deg;
if (a.x * a.z < 0)
theta = 360.0f - theta;
if (theta >= 292.5f && theta < 337.5f)
return 7;
else if (theta >= 22.5f && theta < 67.5f)
return 1;
else if (theta >= 67.5f && theta < 112.5f)
return 2;
else if (theta >= 112.5f && theta < 157.5f)
return 3;
else if (theta >= 157.5f && theta < 202.5f)
return 4;
else if (theta >= 202.5f && theta < 247.5f)
return 5;
else if (theta >= 247.5f && theta < 292.5f)
return 6;
else if (theta >= 337.5f || theta < 22.5f)
return 0;
else return 0;
}
private Rect guiPos = new Rect(0, 0, 720, 30);
void OnGUI()
{
GUI.Label(guiPos, "Angle from the Player is: " + theta + " and forward=" + transform.forward + " and vectorToTarget=" + a);
}
}
and if that needs a little more context, here's my project: https://github.com/AdamRGrey/22623013
I'd recommend hitting play but watching the scene window instead of the game window.

Maybe I'm not understanding the exact effect you're trying to create here (And if so please provide more information such as screenshots in your post), but you should be able to simply use Transform.LookAt(). These are typically called Billboard Sprites.
Example:
Transform.LookAt(Camera.main.transform.position, Vector3.up)

I guess what you are mentioning is the concept of Billboards.
Here is a sample in unity wiki for creating Billboards that always face Camera, go ahead and give it a try.
http://wiki.unity3d.com/index.php?title=CameraFacingBillboard

Collision response and elastic impulse in XNA 4.0

I know there are physic plugins for C# or XNA, but I want to create my own, so I can learn about the topic.
My problems are the following:
I try to apply an elastic impulse to my character with the right angle and velocity. The velocity is calculated the right way, the angle is not and distorts the results!
The next problem is, that my character gets into a shaking mode, though it should stand still. I know where the problem comes from, but I don't know how to fix it (edit: do I have to consider the penetration depth for that?)
The IPhysicsObject inherits the most important informations, the Vector2[] has the collisionPoint at index 0 and the penetration depth at index 1.
I have tried to work with this but yeah.. I don't know
public void ElasticImpulse(IPhysicsObject Object, Vector2[] _colPos)
{
//this function is down below
if (checkCollidingObjects(m_cCharacter, Object))
return;
//this List is like this declined:
//public static List<IPhysicsObject[]> CollidingObjects = new List<IPhysicsObject[]>();
//this list contains every pair of objects, that collided this frame, it is cleared after all physics and game logic is done.
CollidingObjects.Add(new IPhysicsObject[] { m_cCharacter, Object });
//deltavelocity is the velocity between two frames
Vector2 v1 = Velocity - DeltaVelocity;
float lv1 = (float)Math.Sqrt(v1.X * v1.X + v1.Y * v1.Y);
float m1 = Mass;
float k1 = Damping;
Vector2 v2 = Object.Physik.Velocity - Object.Physik.DeltaVelocity;
float lv2 = (float)Math.Sqrt(v2.X * v2.X + v2.Y * v2.Y);
float m2 = Object.Mass;
float k2 = Object.Physik.Damping;
Vector2 colDir1 = _colPos[0] - m_cCharacter.Position;
Vector2 colDir2 = _colPos[0] - Object.Position;
colDir1.Normalize();
colDir2.Normalize();
Vector2 colNorm1 = new Vector2(colDir1.Y, -colDir1.X);
Vector2 colNorm2 = new Vector2(colDir2.Y, -colDir2.X);
float ldir1 = (float)Math.Sqrt(colNorm1.X * colNorm1.X + colNorm1.Y * colNorm1.Y);
float ldir2 = (float)Math.Sqrt(colNorm2.X * colNorm2.X + colNorm2.Y * colNorm2.Y);
float pi = MathHelper.Pi;
//float angle1 = pi - ((v1.X * colNorm1.X + v2.Y * colNorm1.Y) / (lv1 * ldir1)) / v1.Length();
float angle1 = pi - (float)Math.Acos(((v1.X * colNorm1.X + v2.Y * colNorm1.Y) / (lv1 * ldir1)) / v1.Length());
angle1 = (float.IsNaN(angle1)) ? 0 : angle1;
//float angle2 = pi - ((v2.X * colNorm2.X + v2.Y * colNorm2.Y) / (lv2 * ldir1)) / v2.Length();
float angle2 = pi - (float)Math.Acos(((v2.X * colNorm2.X + v2.Y * colNorm2.Y) / (lv2 * ldir1)) / v2.Length());
angle2 = (float.IsNaN(angle2)) ? 0 : angle2;
//calculating the new velocities u 1/2. Got this formula out of the wiki link i posted above (took the german wiki version)
Vector2 u1 = (m1 * v1 + m2 * v2 - (m2 * (v1 - v2) * k2)) / (m1 + m2) - v1;
Vector2 u2 = (m1 * v1 + m2 * v2 - (m1 * (v2 - v1) * k1)) / (m1 + m2) - v2;
//transform the new velocities by the correct angle
Vector2 newV1 = new Vector2(
u1.X * (float)Math.Cos(angle1) - u1.Y * (float)Math.Sin(angle1),
u1.X * (float)Math.Sin(angle1) + u1.Y * (float)Math.Cos(angle1));
Vector2 newV2 = new Vector2(
u2.X * (float)Math.Cos(angle2) - u2.Y * (float)Math.Sin(angle2),
u2.X * (float)Math.Sin(angle2) + u2.Y * (float)Math.Cos(angle2));
newV1 = new Vector2(
(float.IsNaN(newV1.X)) ? 0 : newV1.X,
(float.IsNaN(newV1.Y)) ? 0 : newV1.Y);
newV2 = new Vector2(
(float.IsNaN(newV2.X)) ? 0 : newV2.X,
(float.IsNaN(newV2.Y)) ? 0 : newV2.Y);
AddForce(newV1);
Object.Physik.AddForce(newV2);
}
bool checkCollidingObjects(IPhysicsObject obj1, IPhysicsObject obj2)
{
if (CollidingObjects.Count > 0)
{
int a = CollidingObjects.FindIndex(x => (x[0] == obj1 && x[1] == obj2) ||
(x[1] == obj1 && x[0] == obj2));
return a != -1;
}
return false;
}