Curved plane for Unity

CurvedPlane.cs

using UnityEngine;

[RequireComponent(typeof(MeshFilter))]
[RequireComponent(typeof(MeshRenderer))]
public class CurvedPlane : MonoBehaviour
{
    private class MeshData
    {
        public Vector3[] Vertices { get; set; }
        public Vector2[] Uvs { get; set; }
        public int[] Triangles { get; set; }
    }

    [SerializeField] private float height = 1f;
    [SerializeField] private float radius = 2f;
    
    [SerializeField] [Range(1, 1024)] private int numSegments = 32;
    [SerializeField] [Range(0f, 360f)] private float curvatureDegrees = 60f;
    
    [SerializeField] private bool useArc = true;
    [SerializeField] private bool flipNormals = false;

    private MeshData plane;

    void Start()
    {
        Generate();
    }

    void OnValidate()
    {
        Generate();
    }

    [ContextMenu("Generate")]
    public void Generate()
    {
        GenerateScreen();
        UpdateMeshFilter();
    }

    private void UpdateMeshFilter()
    {
        var filter = GetComponent<MeshFilter>();
        var mesh = new Mesh
        {
            vertices = plane.Vertices,
            uv = plane.Uvs,
            triangles = plane.Triangles
        };
        mesh.RecalculateNormals();
        mesh.RecalculateBounds();
        filter.mesh = mesh;
    }

    private void GenerateScreen()
    {
        plane = new MeshData
        {
            Vertices = new Vector3[(numSegments + 2) * 2],
            Uvs = new Vector2[(numSegments + 2) * 2],
            Triangles = new int[numSegments * 6]
        };

        int i, j;
        for (i = j = 0; i < numSegments + 1; i++)
        {
            GenerateVertexPair(ref i, ref j);
            if (i < numSegments)
            {
                GenerateLeftTriangle(ref i, ref j);
                GenerateRightTriangle(ref i, ref j);
            }
        }
    }

    private void GenerateVertexPair(ref int i, ref int j)
    {
        float amt = ((float)i) / numSegments;
        float arcDegrees = curvatureDegrees * Mathf.Deg2Rad;
        float theta = -0.5f + amt;

        var x = useArc ? Mathf.Sin(theta * arcDegrees) * radius : (-0.5f * radius) + (amt * radius);
        var z = Mathf.Cos(theta * arcDegrees) * radius;

        plane.Vertices[i] = new Vector3(x, height / 2f, z);
        plane.Vertices[i + numSegments + 1] = new Vector3(x, -height / 2f, z);

        plane.Uvs[i] = new Vector2(amt, 1f);
        plane.Uvs[i + numSegments + 1] = new Vector2(amt, 0f);
    }

    private void GenerateLeftTriangle(ref int i, ref int j)
    {
        plane.Triangles[j++] = i;
        plane.Triangles[j++] = flipNormals ? i + numSegments + 1 : i + 1;
        plane.Triangles[j++] = flipNormals ? i + 1 : i + numSegments + 1;
    }

    private void GenerateRightTriangle(ref int i, ref int j)
    {
        plane.Triangles[j++] = i + 1;
        plane.Triangles[j++] = flipNormals ? i + numSegments + 1 : i + numSegments + 2;
        plane.Triangles[j++] = flipNormals ? i + numSegments + 2 : i + numSegments + 1;
    }
}

I would suggest adding UVs to it.
You would just need to ad a uv array in the Mesh Data Set class, fill it like this after you set the vertices:

plane.UVs[i] = new Vector2(i / (float)numSegments, 1);
plane.UVs[i + numSegments + 1] = new Vector2(i / (float)numSegments, 0);

and then attach it to the mesh.