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Struggling to create a trajectory prediction in Unity with 2D physics simulation

I have a 2D brick breaker style game in Unity where you get to choose the angle of your shot before each turn with the mouse. I'd like to show an accurate trajectory prediction of what a ball will do while the player is aiming, up to maybe 200 frames of ball movement (for now). This involves potentially bouncing off the top, left, and right walls, and any bricks.
I'm using a physics simulation and line renderer to accomplish this but can't get it to work correctly.
It's supposed to copy the gun, walls, and bricks into a virtual Scene, launch a ball in the angle the player is aiming, simulate 200 frames of movement, and plot those in a line renderer.
Here is an abridged version of the game code, reduced to just focus on the aiming and physics simulation for the 1st turn. When I run it, it simply plots the 200 points of the line renderer in the same coordinates as the gun.
What am I doing wrong? Thank you!
using UnityEngine;
using UnityEngine.SceneManagement;
public class Aim3 : MonoBehaviour
{
private Vector3 gunPosScreenV3, aimPointScreenV3,
aimPointWorldV3, aimDirectionV3;
private Vector2 ballDirection, ballVelocity;
[SerializeField] private GameObject gun, walls, bricks;
Camera cam;
LineRenderer lr;
// For Physics Scene
private int maxPhysicsFrameIterations = 200;
private Scene simulationScene;
private PhysicsScene2D physicsScene;
[SerializeField] private GameObject ballPrefab;
private GameObject ghostObj;
void Start()
{
lr = GetComponent<LineRenderer>();
lr.enabled = true;
cam = Camera.main;
CreatePhysicsScene();
}
void Update()
{
DrawTrajectory();
}
// This is run once to create a duplicate of the game board for the physics simulation
private void CreatePhysicsScene()
{
simulationScene = SceneManager.CreateScene("Simulation", new CreateSceneParameters(LocalPhysicsMode.Physics2D));
physicsScene = simulationScene.GetPhysicsScene2D();
// Copy the gun to the simulated scene
ghostObj = Instantiate(gun.gameObject, gun.transform.position, gun.transform.rotation);
ghostObj.GetComponent<SpriteRenderer>().enabled = false;
SceneManager.MoveGameObjectToScene(ghostObj, simulationScene);
// Copy all the bricks to the simulated scene. These are stored under a parent Game Object that
// is attached in the editor
foreach (Transform obj in bricks.transform)
{
ghostObj = Instantiate(obj.gameObject, obj.position, obj.rotation);
ghostObj.GetComponent<SpriteRenderer>().enabled = false;
SceneManager.MoveGameObjectToScene(ghostObj, simulationScene);
}
// Copy the top, left, and right walls to the simulated scene. These are invisible and don't have sprites.
// These are stored under a parent Game Object that is attached in the editor
foreach (Transform obj in walls.transform)
{
ghostObj = Instantiate(obj.gameObject, obj.position, obj.rotation);
SceneManager.MoveGameObjectToScene(ghostObj, simulationScene);
}
} // CreatePhysicsScene
private void DrawTrajectory()
{
// Get the starting Screen position of the gun from the World position
gunPosScreenV3 = cam.WorldToScreenPoint(gun.transform.position);
gunPosScreenV3.z = 1;
// Get position of mouse in screen units
aimPointScreenV3 = Input.mousePosition;
// Get the position of the mouse in world units for aiming
aimPointWorldV3 = cam.ScreenToWorldPoint(aimPointScreenV3);
aimPointWorldV3.z = 1;
// Calculate the normalized direction of the aim point compared to the gun
aimDirectionV3 = (aimPointScreenV3 - gunPosScreenV3).normalized;
Physics2D.simulationMode = SimulationMode2D.Script;
// Instantiate the ball prefab for the simulation
ghostObj = Instantiate(ballPrefab, gun.transform.position, Quaternion.identity);
// Assign the ball's velocity
ballDirection = new Vector2(aimDirectionV3.x, aimDirectionV3.y);
ballVelocity = ballDirection * 20f;
ghostObj.GetComponent<Rigidbody2D>().velocity = ballVelocity;
SceneManager.MoveGameObjectToScene(ghostObj.gameObject, simulationScene);
lr.positionCount = maxPhysicsFrameIterations;
for (var i = 0; i < maxPhysicsFrameIterations; i++)
{
physicsScene.Simulate(Time.fixedDeltaTime);
//Physics2D.Simulate(Time.fixedDeltaTime);
lr.SetPosition(i, ghostObj.transform.position);
}
Destroy(ghostObj);
Physics2D.simulationMode = SimulationMode2D.Update;
} // DrawTrajectory
}

You use aimPointScreenV3 but it appears to never be initialized/calculated.

Found the answer. Just needed to add the velocity to the ball after moving it to the simulated scene.
SceneManager.MoveGameObjectToScene(ghostObj.gameObject, simulationScene);
ghostObj.GetComponent<Rigidbody2D>().velocity = ballVelocity;

Pan Tool Algorithm being very jumpy

Looking for a bit of help to see how I can make this algorithm a little better. So I have some code for a pan tool that moves the camera based on the user dragging the mouse to move the camera around. However it is really jumpy unless it is done in really short drags. I.e. the objects in the scene appear to vibrate, which is more likely to be the camera and canvas 'vibrating' rather than the objects themselves.
The code works by toggling a dragging boolean using the SystemEvent methods OnPointerDown and OnPointerUp and assigns a MouseStart Vector3 in world coordinates and also a CameraStart Vector3.
public void OnPointerDown(PointerEventData EventData)
{
if (!dragging)
{
dragging = true;
MouseStart = new Vector3(Camera.main.ScreenToWorldPoint(Input.mousePosition).x, Camera.main.ScreenToWorldPoint(Input.mousePosition).y, 0f);
CameraStart = TheCamera.transform.position;
}
}
public void OnPointerUp(PointerEventData EventData)
{
if (dragging)
{
dragging = false;
}
}
Then in the update loop while the dragging variable is true, xChange and yChange float values are determined based on the current mouse position compared to the original mouse position, the camera position is then adjusted according to these. My thought process was that because it is relative to a fixed MouseStart (because it is only changed in the single frame where the pointer is clicked and dragging = 0) that if I were to drag and then say keep the mouse still, there would be no change in coordinates as it'd be repeatedly putting the Camera in the same position. The full code looks like this:
private bool dragging;
private string CurrentTool;
private ButtonController[] DrawingTools;
public Camera TheCamera;
public Vector3 MouseStart;
public Vector3 CameraStart;
public float sensitivity;
// Use this for initialization
void Start () {
TheCamera = FindObjectOfType<Camera>();
DrawingTools = FindObjectsOfType<ButtonController>();
}
// Update is called once per frame
void Update () {
for (int i = 0; i < DrawingTools.Length; i++)
{
if (DrawingTools[i].Pressed)
{
CurrentTool = DrawingTools[i].gameObject.name;
}
}
if (dragging && CurrentTool == "PanTool Button")
{
float xChange;
float yChange;
Vector3 MousePosition = Camera.main.ScreenToWorldPoint(Input.mousePosition);
if (MousePosition.x > MouseStart.x)
{
xChange = -Mathf.Abs(MousePosition.x - MouseStart.x);
}
else
{
xChange = Mathf.Abs(MousePosition.x - MouseStart.x);
}
if (MousePosition.y > MouseStart.y)
{
yChange = -Mathf.Abs(MousePosition.y - MouseStart.y);
}
else
{
yChange = Mathf.Abs(MousePosition.y - MouseStart.y);
}
TheCamera.transform.position = new Vector3(CameraStart.x + xChange*sensitivity, CameraStart.y + yChange*sensitivity, CameraStart.z);
}
}
public void OnPointerDown(PointerEventData EventData)
{
if (!dragging)
{
dragging = true;
MouseStart = new Vector3(Camera.main.ScreenToWorldPoint(Input.mousePosition).x, Camera.main.ScreenToWorldPoint(Input.mousePosition).y, 0f);
CameraStart = TheCamera.transform.position;
}
}
public void OnPointerUp(PointerEventData EventData)
{
if (dragging)
{
dragging = false;
}
}
Any help is appreciated, thanks.
EDIT: Just to clarify this is a 2d environment

This is happening because the Camera from which you are determining the world position of the mouse is being updated every frame according to the world position of the mouse, which causes a feedback loop (and therefore noise + jitter).
You can reduce noise from the feedback loop by smoothing the Camera's movement over time (effectively a low pass), or try to remove the feedback loop entirely by altering your calculations so the camera position and target position (mouse) don't rely on each other - although I'm not sure how to go about that if it's actually possible for your intent.
Check out Vector3.SmoothDamp.
Gradually changes a vector towards a desired goal over time.
The vector is smoothed by some spring-damper like function, which will
never overshoot. The most common use is for smoothing a follow camera.

Issues with transform.Rotate in Unity

I have been working on programming a graph in Unity that rotates based on head movement. I have been having multiple issues with the rotation aspect of it.
A sample of the Autowalk class, which I am using to find the angle that the graph needs to rotate based on where the user is facing:
public class AutoWalk : MonoBehaviour {
//VR head
private Transform vrHead;
//angular displacement from normal
public float xAng, yAng, zAng;
//previous values
public float xOrig, yOrig, zOrig;
// Use this for initialization
void Start () {
//Find the VR head
vrHead = Camera.main.transform;
//finding the initial direction
Vector3 orig = vrHead.TransformDirection(Vector3.forward);
xOrig = orig.x;
yOrig = orig.y;
zOrig = orig.z;
}
// Update is called once per frame
void Update () {
//find the forward direction
Vector3 forward = vrHead.TransformDirection(Vector3.forward);
float xForward = forward.x;
float yForward = forward.y;
float zForward = forward.z;
//find the angle between the initial and current direction
xAng = Vector3.Angle(new Vector3(xOrig, 0, 0), new Vector3(xForward, 0, 0));
yAng = Vector3.Angle(new Vector3(0, yOrig, 0), new Vector3(0, yForward, 0));
zAng = Vector3.Angle(new Vector3(0, 0, zOrig), new Vector3(0, 0, zForward));
//set new original angle
xOrig = xAng;
yOrig = yAng;
zOrig = zAng;
}
From there I go to the ReadingPoints class, which contains all of the points on the graphs (spheres) and axes (stretched out cubes):
public class ReadingPoints : MonoBehaviour {
// Update is called once per frame
void Update () {
float xAngl = GameObject.Find("GvrMain").GetComponent<AutoWalk>().xAng;
float yAngl = GameObject.Find("GvrMain").GetComponent<AutoWalk>().yAng;
float zAngl = GameObject.Find("GvrMain").GetComponent<AutoWalk>().zAng;
if ((xAngl != prevXAngl) || (yAngl!=prevYAngl) || (zAngl!=prevZAngl))
{
//rotate depending on the angle from normal
foreach (GameObject o in allObjects)
{
o.transform.Rotate(new Vector3(xAngl, yAngl, zAngl), Space.World);
prevXAngl = xAngl;
prevYAngl = yAngl;
prevZAngl = zAngl;
}
}
allObjects, as the name implies, contains the points and the axes.
Anyway, the first issue that is upon running the program is that the graph appears to be torn apart.
How the graph is supposed to look (this is what it looks like when o.transform.Rotate(...) is commented out)
Here is how it actually looks :( Also, the graph does not rotate when I move, and I have no idea why (I thought I might be using the Rotate function improperly but perhaps I also didn't find the correct angles?). Any ideas of what went wrong are much appreciated, thank you!

First of all I think you should start using Quaternions (https://docs.unity3d.com/ScriptReference/Quaternion.html)
Secondly; while you rotate a object with a Camera attached its line of view will change and eventually the object(Graph) will be out of view. If you want as much of the full graph as possible to remain in view of camera as long as possible. You should give the Quaternion of the graph the opposite rotation of that applied to your Camera or the object it is attached to.
Make sure your all elements of your graph are children of a central gameobject in your graph, and only manipulate that point.

How can i create an in-game system that lets me draw lines with the cursor that can act as walkable terrain

Hi im creating a 2D platformer, and i want to be able to draw for example lines ingame (playmode) with my cursor (like paint) that can act as walkable terrain. Im pretty new to coding and c# which im using, and im having a really hard time imagining how this can be achieved let alone if its possible? Would appreciate if you guys could give me some ideas and maybe could help me push it in the right direction. Thanks!
EDIT:
So i got got some code now which makes me being able to draw in playmode. The question now is how i can implement a type of collider to this? Maybe each dot can represent a little square or something? How can i go through with it? Heres some code. Thanks.
using UnityEngine;
using System.Collections;
using System.Collections.Generic;
public class DrawLine : MonoBehaviour
{
private LineRenderer line;
private bool isMousePressed;
private List<Vector3> pointsList;
private Vector3 mousePos;
// Structure for line points
struct myLine
{
public Vector3 StartPoint;
public Vector3 EndPoint;
};
// -----------------------------------
void Awake()
{
// Create line renderer component and set its property
line = gameObject.AddComponent<LineRenderer>();
line.material = new Material(Shader.Find("Particles/Additive"));
line.SetVertexCount(0);
line.SetWidth(0.1f,0.1f);
line.SetColors(Color.green, Color.green);
line.useWorldSpace = true;
isMousePressed = false;
pointsList = new List<Vector3>();
}
// -----------------------------------
void Update ()
{
// If mouse button down, remove old line and set its color to green
if(Input.GetMouseButtonDown(0))
{
isMousePressed = true;
line.SetVertexCount(0);
pointsList.RemoveRange(0,pointsList.Count);
line.SetColors(Color.green, Color.green);
}
else if(Input.GetMouseButtonUp(0))
{
isMousePressed = false;
}
// Drawing line when mouse is moving(presses)
if(isMousePressed)
{
mousePos = Camera.main.ScreenToWorldPoint(Input.mousePosition);
mousePos.z=0;
if (!pointsList.Contains (mousePos))
{
pointsList.Add (mousePos);
line.SetVertexCount (pointsList.Count);
line.SetPosition (pointsList.Count - 1, (Vector3)pointsList [pointsList.Count - 1]);
}
}
}
}

Regarding means and tools:
Input.mousePosition
Input.GetKey, Input.GetKeyDown, Input.GetKeyUp
Line renderer manual
Line renderer scripting API
Regarding general idea:
Your script may use Input.GetKey to trigger the feature functionality (keyboard key, for example).
When the feature is activated the script awaits of mouse button to be clicked by the means of Input.GetKeyUp and when the event happens it must capture current mouse position using Input.mousePosition.
Only two points are necessary to build a segment of line, so when the script detects input of the second point it may create game object that will represent a piece of walkable terrain.
Visually such an object may be represented with line renderer. To enable iteraction with other game objects (like player character) it is usually enough to enhance object with a collider component (presumably, with a BoxCollider).
Regarding of how-to-add-a-collider:
GameObject CreateLineCollider(Vector3 point1, Vector3 point2, float width)
{
GameObject obj = new GameObject("LineCollider");
obj.transform.position = (point1+point2)/2;
obj.transform.right = (point2-point1).normalized;
BoxCollider boxCollider = obj.AddComponent<BoxCollider>();
boxCollider.size = new Vector3( (point2-point1).magnitude, width, width );
return obj;
}
You can add collider to object with line renderer but you still must orient it properly.
Example of integration in your code:
void Update ()
{
...
// Drawing line when mouse is moving(presses)
if(isMousePressed)
{
mousePos = Camera.main.ScreenToWorldPoint(Input.mousePosition);
mousePos.z=0;
if (!pointsList.Contains (mousePos))
{
pointsList.Add (mousePos);
line.SetVertexCount (pointsList.Count);
line.SetPosition (pointsList.Count - 1, (Vector3)pointsList [pointsList.Count - 1]);
const float ColliderWidth = 0.1f;
Vector3 point1 = pointsList[pointsList.Count - 2];
Vector3 point2 = pointsList[pointsList.Count - 1];
GameObject obj = new GameObject("SubCollider");
obj.transform.position = (point1+point2)/2;
obj.transform.right = (point2-point1).normalized;
BoxCollider boxCollider = obj.AddComponent<BoxCollider>();
boxCollider.size = new Vector3( (point2-point1).magnitude, ColliderWidth , ColliderWidth );
obj.transform.parent = this.transform;
}
}
}

Move Camera Over Terrain Using Touch Input in Unity 3D

I am new to Unity and I am trying to figure out how to move the camera over a map/terrain using touch input. The camera would be looking down at the terrain with a rotation of (90,0,0). The terrain is on layer 8. I have had no problem getting it moving with keyboard, now I am trying to move to touch and it is very different if you want to keep expected usage on iOS.
The best example I can think of on a built in iOS app is Maps where the user would touch the screen and that point on the map would stay under the finger as long as the finger stayed on the screen. So as the user moves their finger the map appears to be moving with the finger. I have not been able to find examples that show how to do it this way. I have seen may examples of moving the camera or character with the mouse but they don't seem to translate well to this style.
Also posted on Unity3D Answers:
http://answers.unity3d.com/questions/283159/move-camera-over-terrain-using-touch-input.html

Below should be what you need. Note that it's tricky to get a 1 to 1 correspondence between finger/cursor and the terrain when using a perspective camera. If you change your camera to orthographic, the script below should give you a perfect map between finger/cursor position and map movement. With perspective you'll notice a slight offset.
You could also do this with ray tracing but I've found that route to be sloppy and not as intuitive.
Camera settings for testing (values are pulled from the inspector so apply them there):
Position: 0,20,0
Orientation: 90,0,0
Projection: Perspective/Orthographic
using UnityEngine;
using System.Collections;
public class ViewDrag : MonoBehaviour {
Vector3 hit_position = Vector3.zero;
Vector3 current_position = Vector3.zero;
Vector3 camera_position = Vector3.zero;
float z = 0.0f;
// Use this for initialization
void Start () {
}
void Update(){
if(Input.GetMouseButtonDown(0)){
hit_position = Input.mousePosition;
camera_position = transform.position;
}
if(Input.GetMouseButton(0)){
current_position = Input.mousePosition;
LeftMouseDrag();
}
}
void LeftMouseDrag(){
// From the Unity3D docs: "The z position is in world units from the camera." In my case I'm using the y-axis as height
// with my camera facing back down the y-axis. You can ignore this when the camera is orthograhic.
current_position.z = hit_position.z = camera_position.y;
// Get direction of movement. (Note: Don't normalize, the magnitude of change is going to be Vector3.Distance(current_position-hit_position)
// anyways.
Vector3 direction = Camera.main.ScreenToWorldPoint(current_position) - Camera.main.ScreenToWorldPoint(hit_position);
// Invert direction to that terrain appears to move with the mouse.
direction = direction * -1;
Vector3 position = camera_position + direction;
transform.position = position;
}
}

I've come up with this script (I have appended it to the camera):
private Vector2 worldStartPoint;
void Update () {
// only work with one touch
if (Input.touchCount == 1) {
Touch currentTouch = Input.GetTouch(0);
if (currentTouch.phase == TouchPhase.Began) {
this.worldStartPoint = this.getWorldPoint(currentTouch.position);
}
if (currentTouch.phase == TouchPhase.Moved) {
Vector2 worldDelta = this.getWorldPoint(currentTouch.position) - this.worldStartPoint;
Camera.main.transform.Translate(
-worldDelta.x,
-worldDelta.y,
0
);
}
}
}
// convert screen point to world point
private Vector2 getWorldPoint (Vector2 screenPoint) {
RaycastHit hit;
Physics.Raycast(Camera.main.ScreenPointToRay(screenPoint), out hit);
return hit.point;
}

Pavel's answer helped me a lot, so wanted to share my solution with the community in case it helps others. My scenario is a 3D world with an orthographic camera. A top-down style RTS I am working on. I want pan and zoom to work like Google Maps, where the mouse always stays at the same spot on the map when you pan and zoom. This script achieves this for me, and hopefully is robust enough to work for others' needs. I haven't tested it a ton, but I commented the heck out of it for beginners to learn from.
using UnityEngine;
// I usually attach this to my main camera, but in theory you can attach it to any object in scene, since it uses Camera.main instead of "this".
public class CameraMovement : MonoBehaviour
{
private Vector3 MouseDownPosition;
void Update()
{
// If mouse wheel scrolled vertically, apply zoom...
// TODO: Add pinch to zoom support (touch input)
if (Input.mouseScrollDelta.y != 0)
{
// Save location of mouse prior to zoom
var preZoomPosition = getWorldPoint(Input.mousePosition);
// Apply zoom (might want to multiply Input.mouseScrollDelta.y by some speed factor if you want faster/slower zooming
Camera.main.orthographicSize = Mathf.Clamp(Camera.main.orthographicSize + Input.mouseScrollDelta.y, 5, 80);
// How much did mouse move when we zoomed?
var delta = getWorldPoint(Input.mousePosition) - preZoomPosition;
// Rotate camera to top-down (right angle = 90) before applying adjustment (otherwise we get "slide" in direction of camera angle).
// TODO: If we allow camera to rotate on other axis we probably need to adjust that also. At any rate, you want camera pointing "straight down" for this part to work.
var rot = Camera.main.transform.localEulerAngles;
Camera.main.transform.localEulerAngles = new Vector3(90, rot.y, rot.z);
// Move the camera by the amount mouse moved, so that mouse is back in same position now.
Camera.main.transform.Translate(delta.x, delta.z, 0);
// Restore camera rotation
Camera.main.transform.localEulerAngles = rot;
}
// When mouse is first pressed, just save location of mouse/finger.
if (Input.GetMouseButtonDown(0))
{
MouseDownPosition = getWorldPoint(Input.mousePosition);
}
// While mouse button/finger is down...
if (Input.GetMouseButton(0))
{
// Total distance finger/mouse has moved while button is down
var delta = getWorldPoint(Input.mousePosition) - MouseDownPosition;
// Adjust camera by distance moved, so mouse/finger stays at exact location (in world, since we are using getWorldPoint for everything).
Camera.main.transform.Translate(delta.x, delta.z, 0);
}
}
// This works by casting a ray. For this to work well, this ray should always hit your "ground". Setup ignore layers if you need to ignore other colliders.
// Only tested this with a simple box collider as ground (just one flat ground).
private Vector3 getWorldPoint(Vector2 screenPoint)
{
RaycastHit hit;
Physics.Raycast(Camera.main.ScreenPointToRay(screenPoint), out hit);
return hit.point;
}
}

Based on the answer from Pavel, I simplified the script and removed the unlovely "jump" when touch with more then one finger and release the second finger:
private bool moreThenOneTouch = false;
private Vector3 worldStartPoint;
void Update() {
Touch currentTouch;
// only work with one touch
if (Input.touchCount == 1 && !moreThenOneTouch) {
currentTouch = Input.GetTouch(0);
if (currentTouch.phase == TouchPhase.Began) {
this.worldStartPoint = Camera.main.ScreenToWorldPoint(currentTouch.position);
}
if (currentTouch.phase == TouchPhase.Moved) {
Vector3 worldDelta = Camera.main.ScreenToWorldPoint(currentTouch.position) - this.worldStartPoint;
Camera.main.transform.Translate(
-worldDelta.x,
-worldDelta.y,
0
);
}
}
if (Input.touchCount > 1) {
moreThenOneTouch = true;
} else {
moreThenOneTouch = false;
if(Input.touchCount == 1)
this.worldStartPoint = Camera.main.ScreenToWorldPoint(Input.GetTouch(0).position);
}
}

using UnityEngine;
// I usually attach this to my main camera, but in theory you can attach it to any object in scene, since it uses Camera.main instead of "this".
public class CameraMovement : MonoBehaviour
{
private Vector3 MouseDownPosition;
void Update()
{
// If mouse wheel scrolled vertically, apply zoom...
// TODO: Add pinch to zoom support (touch input)
if (Input.mouseScrollDelta.y != 0)
{
// Save location of mouse prior to zoom
var preZoomPosition = getWorldPoint(Input.mousePosition);
// Apply zoom (might want to multiply Input.mouseScrollDelta.y by some speed factor if you want faster/slower zooming
Camera.main.orthographicSize = Mathf.Clamp(Camera.main.orthographicSize + Input.mouseScrollDelta.y, 5, 80);
// How much did mouse move when we zoomed?
var delta = getWorldPoint(Input.mousePosition) - preZoomPosition;
// Rotate camera to top-down (right angle = 90) before applying adjustment (otherwise we get "slide" in direction of camera angle).
// TODO: If we allow camera to rotate on other axis we probably need to adjust that also. At any rate, you want camera pointing "straight down" for this part to work.
var rot = Camera.main.transform.localEulerAngles;
Camera.main.transform.localEulerAngles = new Vector3(90, rot.y, rot.z);
// Move the camera by the amount mouse moved, so that mouse is back in same position now.
Camera.main.transform.Translate(delta.x, delta.z, 0);
// Restore camera rotation
Camera.main.transform.localEulerAngles = rot;
}
// When mouse is first pressed, just save location of mouse/finger.
if (Input.GetMouseButtonDown(0))
{
MouseDownPosition = getWorldPoint(Input.mousePosition);
}
// While mouse button/finger is down...
if (Input.GetMouseButton(0))
{
// Total distance finger/mouse has moved while button is down
var delta = getWorldPoint(Input.mousePosition) - MouseDownPosition;
// Adjust camera by distance moved, so mouse/finger stays at exact location (in world, since we are using getWorldPoint for everything).
Camera.main.transform.Translate(delta.x, delta.z, 0);
}
}
// This works by casting a ray. For this to work well, this ray should always hit your "ground". Setup ignore layers if you need to ignore other colliders.
// Only tested this with a simple box collider as ground (just one flat ground).
private Vector3 getWorldPoint(Vector2 screenPoint)
{
RaycastHit hit;
Physics.Raycast(Camera.main.ScreenPointToRay(screenPoint), out hit);
return hit.point;
}
}