hi. i have some CAD mathematics equations that lead to draw close shape. how i can make a 3d mesh from it in unity ? it must be completely automatic system .any idea?
Your solution will be in two steps:

convert your equations to Vector3 coordinates. The example you show looks like it has two straight lines which would need a Vector3 at each end, but the curved ones would require you to split them up. Maybe you could solve for a x coordinate at 5 or 6 spots along the curve to get those points?

Add a GameObject to your scene with a MeshRenderer component and MeshFilter component added to it. Then dynamically create a mesh object with the coordinates you found in part one. This script should get you started:
using UnityEngine;
[RequireComponent(typeof(MeshFilter))]
[RequireComponent(typeof(MeshRenderer))]public class DynamicSquare : MonoBehaviour {
private Vector3[] vertices; private int[] triangles; // private Vector2[] uvs; // if you want to add uv coordinates void Start () { /* The vertex indicies look like this, with these triangles * 3  0 *  / *  /  *  /  * /  * 2  1 */ // the 4 vertices making up our square counterclockwise from top right vertices = new Vector3[4]; vertices[0] = new Vector3(1, 1, 0); vertices[1] = new Vector3(1, 0, 0); vertices[2] = new Vector3(0, 0, 0); vertices[3] = new Vector3(0, 1, 0); // list of index locations for the vertices making up each triangle triangles = new int[6]; triangles[0] = 0; triangles[1] = 1; triangles[2] = 2; triangles[3] = 0; triangles[4] = 2; triangles[5] = 3; Mesh mesh = new Mesh(); mesh.vertices = vertices; mesh.triangles = triangles; //mesh.uvs = uvs; //< If you want to create uvs to map to a texture mesh.name = "DynamicSquareMesh"; GetComponent<MeshFilter>().mesh = mesh; }
}