How do I restrict object movement in the Y-Axis 3D

Questions & Answers
1

I want to move my object along the X-Z plane only and restrit the Y-axis. Here is my code:

Vector3 mousePosition;
    
    private Vector3 GetMousePos()
    {
        return Camera.main.WorldToScreenPoint(transform.position);
    }

    private void OnMouseDown()
    {
        mousePosition = Input.mousePosition - GetMousePos();
    }

    private void OnMouseDrag()
    {
        transform.position = Camera.main.ScreenToWorldPoint(Input.mousePosition - mousePosition);
    }

Any ideas how I can restrict it?

2

Hi Matthewman96. One way would be like the below:

Vector3 mousPosition = GetMousePos(); 
mouseposition.x = 0;
mouseposition.z = 0;`

Then, the mousPosition value will be (0, REAL_VALUE, 0) I hope it helps.

Or maybe like below:

private Vector3 GetMousePos()
{
    Vector3 pos = Camera.main.WorldToScreenPoint(transform.position);
    pos.x = 0;
    pos.z = 0;
    return pos;
}
3

Hi,

You can use Math:

First, you already have Two Point: the camera pos, and a point caculate by Camera.main.ScreenToWorldPoint and Input.mousePosition and a z-depth but 0.

Then you can get the line equation of these two point.

Finally, you can use a particular Y values to get the point you want from the line equation.

4

Or,

if you have a plane with a Y-value you want to restrict. Then you can use Camera.man.ScreenPointToRay() to get the collision pos. That pos will be your wanted.