LIBMAS/Annotation/FieldView/ViewOval.cs

using PaintDotNet.Annotation.Enum;
using PaintDotNet.Base.CommTool;
using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.Drawing;
using System.Drawing.Drawing2D;
using System.Globalization;
using System.Runtime.Serialization;
using System.Windows.Forms;

namespace PaintDotNet.Annotation.FieldView
{
    /// <summary>
    /// 椭圆形视场绘制
    /// </summary>
    public class ViewOval : ViewBase
    {
        #region Calculate
        List<Func<PointF>> m_ovalTemple;

        float _a;
        float _b;

        float _centerx;
        float _centery;

        float _angle = 0;

        readonly float _sqrt2 = (float)Math.Sqrt(2);

        public override double Width
        {
            get => _a * 2;
            set
            {
                _a = (float)value / 2;
                _centerx = Center.X;
                _centery = Center.Y;
                Points = CalculateCirclePoints();
            }
        }

        public override double Height
        {
            get => _b * 2;
            set
            {
                _b = (float)value / 2;
                _centerx = Center.X;
                _centery = Center.Y;
                Points = CalculateCirclePoints();
            }
        }

        void InitOvalTemplate()
        {
            m_ovalTemple = new List<Func<PointF>>();
            m_ovalTemple.Add(
                new Func<PointF>(() =>
                { return new PointF(-(_a / _sqrt2), -(_b / _sqrt2)); }));
            m_ovalTemple.Add(
                new Func<PointF>(() =>
                { return new PointF(0, -_b); }));
            m_ovalTemple.Add(
                new Func<PointF>(() =>
                { return new PointF((_a / _sqrt2), -(_b / _sqrt2)); }));
            m_ovalTemple.Add(
                new Func<PointF>(() =>
                { return new PointF(_a, 0); }));
            m_ovalTemple.Add(
                new Func<PointF>(() =>
                { return new PointF((_a / _sqrt2), (_b / _sqrt2)); }));
            m_ovalTemple.Add(
                new Func<PointF>(() =>
                { return new PointF(0, _b); }));
            m_ovalTemple.Add(
                new Func<PointF>(() =>
                { return new PointF(-(_a / _sqrt2), (_b / _sqrt2)); }));
            m_ovalTemple.Add(
                new Func<PointF>(() =>
                { return new PointF(-_a, 0); }));
        }

        List<PointF> CalculateCirclePoints()
        {
            List<PointF> points = new List<PointF>();
            foreach (var func in m_ovalTemple)
            {
                var p = func.Invoke();
                p = BasicCalculationHelper.GetAnglePoint(p, _lastCenter, _angle);
                points.Add(new PointF(p.X + _centerx, p.Y + _centery));
            }
            return points;
        }

        /// <summary>
        /// 当PointList被修改时,更新参数
        /// </summary>
        /// <param name="points"></param>
        void ReverseBuild(List<PointF> points)
        {
            _b = (float)(BasicCalculationHelper.GetDistance(points[1], points[5]) / 2);
            _a = (float)(BasicCalculationHelper.GetDistance(points[3], points[7]) / 2);
            _centerx = (points[1].X + points[5].X) / 2;
            _centery = (points[1].Y + points[5].Y) / 2;
            _angle = (float)BasicCalculationHelper.CalculateAngle(new PointF(_centerx, _centery), new PointF(_centerx + 100, _centery), points[3]);
        }

        public override double Getacreage()
        {
            var b = BasicCalculationHelper.GetDistance(Points[1], Points[5]) / 2;
            var a = BasicCalculationHelper.GetDistance(Points[3], Points[7]) / 2;
            return Math.PI * a * b;
        }
        #endregion

        #region Constructor
        public ViewOval()
        {
            this.objectType = DrawClass.View;
            this.drawToolType = DrawToolType.ViewOval;
            Rotatable = true;
            Initialize();
            InitOvalTemplate();
        }

        public ViewOval(int x, int y) : this()
        {
            for (int i = 0; i < 8; i++) AddPoint(x, y);
        }

        public ViewOval(List<PointF> points) : this()
        {
            ReverseBuild(points);
            Points = points;
        }
        #endregion

        public override PointF Center
        {
            get
            {
                var x = (Points[1].X + Points[5].X) / 2;
                var y = (Points[1].Y + Points[5].Y) / 2;
                return new PointF(x, y);
            }
            set { }
        }

        #region Handle
        public override int HandleCount => 9;

        public override PointF GetHandle(int handleNumber)
        {
            if (handleNumber > Points.Count)
            {
                var x = (Center.X + Points[3].X) / 2;
                var y = (Center.Y + Points[3].Y) / 2;
                return new PointF(x, y);
            }
            else
                return Points[handleNumber - 1];
        }

        public override Cursor GetHandleCursor(int handleNumber)
        {
            switch (handleNumber)
            {
                case 9:
                    return m_rotateCursor;
                default:
                    return m_resizeCursor;
            }
        }

        public override void MoveHandleTo(Point point, int handleNumber)
        {
            if (handleNumber == 9) MoveRotate(point);
            else if (handleNumber % 2 != 0)
                MoveCorner(point);
            else
                MoveEdage(point, handleNumber);
            OnPropertyChanged();
        }

        private void MoveCorner(Point point)
        {
            _centerx = Center.X;
            _centery = Center.Y;
            var p = BasicCalculationHelper.GetAnglePoint(point, new PointF(_centerx, _centery), -_angle);
            _a = Math.Abs(p.X - Center.X) * _sqrt2;
            _b = Math.Abs(p.Y - Center.Y) * _sqrt2;
            Points = CalculateCirclePoints();
        }

        protected override void MoveRotate(PointF point)
        {
            _centerx = Center.X;
            _centery = Center.Y;
            _angle = (float)BasicCalculationHelper.CalculateAngle(new PointF(_centerx, _centery), new PointF(_centerx + 100, _centery), point);
            Points = CalculateCirclePoints();
        }

        private void MoveEdage(Point point, int i)
        {
            var o = Points[(i + 3) % 8];
            var p = BasicCalculationHelper.GetAnglePoint(point, o, -_angle);
            var c = BasicCalculationHelper.GetAnglePoint(Center, o, -_angle);
            if (i % 4 == 0)
            {
                c.X = (p.X + o.X) / 2;
                _a = Math.Abs(p.X - o.X) / 2;
            }
            else
            {
                c.Y = (p.Y + o.Y) / 2;
                _b = Math.Abs(p.Y - o.Y) / 2;
            }
            c = BasicCalculationHelper.GetAnglePoint(c, o, _angle);
            _centerx = c.X;
            _centery = c.Y;

            Points = CalculateCirclePoints();
        }
        #endregion 

        #region Clone
        public override DrawObject Clone()
        {
            return Clone(ISurfaceBox);
        }

        public override DrawObject Clone(ISurfaceBox surfaceBox)
        {
            ViewOval drawRectangle = new ViewOval(Points);
            drawRectangle.ISurfaceBox = surfaceBox;
            drawRectangle.combineMode = this.combineMode;
            drawRectangle.Color = Color;
            drawRectangle.ID = ID;
            FillDrawObjectFields(drawRectangle);
            return drawRectangle;
        }
        #endregion
    }
}