Camera.rect

Description

Where on the screen is the camera rendered in normalized coordinates.

The values in rect range from zero (left/bottom) to one (right/top).

using UnityEngine;

// Change the width of the viewport each time space key is pressed

public class ExampleClass : MonoBehaviour
{
    private Camera cam;

    void Start()
    {
        cam = Camera.main;
    }

    void Update()
    {
        if (Input.GetKey("space"))
        {
            // choose the margin randomly
            float margin = Random.Range(0.0f, 0.3f);
            // setup the rectangle
            cam.rect = new Rect(margin, 0.0f, 1.0f - margin * 2.0f, 1.0f);
        }
    }
}