Assets/Scripts/RoomBuilding/PolygonValidator.cs - master - GeekNerd/ServerModelingProject

Assets/Scripts/RoomBuilding/PolygonValidator.cs
122 строки4 KB
Gorney-Alex
Init
30 май 2026, 19:05
30 май 2026, 19:053cdcc49
using System.Collections.Generic;
using UnityEngine;

namespace RoomBuilding
{
    public class PolygonValidator
    {
        public const float MinArea = 14f;
        public const float MinEdgeLength = 0.1f;

        public bool Validate(IReadOnlyList<Vector2> vertices, out string error)
        {
            error = string.Empty;

            if (vertices == null || vertices.Count < 3)
            {
                error = "Polygon must have at least 3 vertices.";
                return false;
            }

            for (int i = 0; i < vertices.Count; i++)
            {
                var a = vertices[i];
                var b = vertices[(i + 1) % vertices.Count];
                if ((b - a).magnitude <= MinEdgeLength)
                {
                    error = $"Degenerate edge detected at index {i}.";
                    return false;
                }
            }

            if (HasSelfIntersections(vertices))
            {
                error = "Polygon has self intersections.";
                return false;
            }

            var area = Mathf.Abs(SignedPolygonArea(vertices));
            if (area <= MinArea)
            {
                error = $"Polygon area is too small: {area:F2} m2.";
                return false;
            }

            return true;
        }

        public static float SignedPolygonArea(IReadOnlyList<Vector2> vertices)
        {
            float area = 0f;
            for (int i = 0; i < vertices.Count; i++)
            {
                var a = vertices[i];
                var b = vertices[(i + 1) % vertices.Count];
                area += a.x * b.y - b.x * a.y;
            }

            return area * 0.5f;
        }

        public static bool IsPointInPolygon(IReadOnlyList<Vector2> polygon, Vector2 point)
        {
            bool inside = false;
            for (int i = 0, j = polygon.Count - 1; i < polygon.Count; j = i++)
            {
                var pi = polygon[i];
                var pj = polygon[j];
                bool intersects =
                    ((pi.y > point.y) != (pj.y > point.y)) &&
                    (point.x < (pj.x - pi.x) * (point.y - pi.y) / (pj.y - pi.y + 1e-6f) + pi.x);

                if (intersects)
                {
                    inside = !inside;
                }
            }

            return inside;
        }

        private static bool HasSelfIntersections(IReadOnlyList<Vector2> vertices)
        {
            for (int i = 0; i < vertices.Count; i++)
            {
                var a1 = vertices[i];
                var a2 = vertices[(i + 1) % vertices.Count];

                for (int j = i + 1; j < vertices.Count; j++)
                {
                    if (Mathf.Abs(i - j) <= 1 || (i == 0 && j == vertices.Count - 1))
                    {
                        continue;
                    }

                    var b1 = vertices[j];
                    var b2 = vertices[(j + 1) % vertices.Count];
                    if (SegmentsIntersect(a1, a2, b1, b2))
                    {
                        return true;
                    }
                }
            }

            return false;
        }

        private static bool SegmentsIntersect(Vector2 p1, Vector2 p2, Vector2 q1, Vector2 q2)
        {
            float o1 = Orientation(p1, p2, q1);
            float o2 = Orientation(p1, p2, q2);
            float o3 = Orientation(q1, q2, p1);
            float o4 = Orientation(q1, q2, p2);

            return o1 * o2 < 0f && o3 * o4 < 0f;
        }

        private static float Orientation(Vector2 a, Vector2 b, Vector2 c)
        {
            return (b.x - a.x) * (c.y - a.y) - (b.y - a.y) * (c.x - a.x);
        }
    }
}