示例

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class Test : MonoBehaviour
{
    public CanvasRenderer canvasRenderer;
    public Color color;
    public Rect clipRect;

    void OnGUI()
    {
        //设置颜色
        canvasRenderer.SetColor(color);
        //设置裁剪区域
        canvasRenderer.EnableRectClipping(clipRect);
    }
}

运行测试