[C#/WINFORM] 오각형(Pentagram) 그리기

TestProject.zip

다운로드

▶ MainForm.cs

using System;
using System.Drawing;
using System.Windows.Forms;

namespace TestProject
{
    /// <summary>
    /// 메인 폼
    /// </summary>
    public partial class MainForm : Form
    {
        //////////////////////////////////////////////////////////////////////////////////////////////////// Field
        ////////////////////////////////////////////////////////////////////////////////////////// Private

        #region Field

        /// <summary>
        /// 파란색 펜
        /// </summary>
        private Pen bluePen;

        /// <summary>
        /// 빨간색 펜
        /// </summary>
        private Pen redPen;

        #endregion

        //////////////////////////////////////////////////////////////////////////////////////////////////// Constructor
        ////////////////////////////////////////////////////////////////////////////////////////// Public

        #region 생성자 - MainForm()

        /// <summary>
        /// 생성자
        /// </summary>
        public MainForm()
        {
            InitializeComponent();

            this.bluePen = new Pen(Brushes.Blue);
            this.redPen  = new Pen(Brushes.Red );

            SetStyle(ControlStyles.ResizeRedraw | ControlStyles.UserPaint | ControlStyles.AllPaintingInWmPaint, true);

            UpdateStyles();
        }

        #endregion

        //////////////////////////////////////////////////////////////////////////////////////////////////// Method
        ////////////////////////////////////////////////////////////////////////////////////////// Protected

        #region 배경 페인트시 처리하기 - OnPaintBackground(e)

        /// <summary>
        /// 배경 페인트시 처리하기
        /// </summary>
        /// <param name="e">이벤트 인자</param>
        protected override void OnPaintBackground(PaintEventArgs e)
        {
            e.Graphics.Clear(Color.White);
        }

        #endregion
        #region 페인트시 처리하기 - OnPaint(e)

        /// <summary>
        /// 페인트시 처리하기
        /// </summary>
        /// <param name="e">이벤트 인자</param>
        protected override void OnPaint(PaintEventArgs e)
        {
            DrawPentagram(e.Graphics);
        }

        #endregion

        ////////////////////////////////////////////////////////////////////////////////////////// Private

        #region 라디안 구하기 - GetRadian(degree)

        /// <summary>
        /// 라디안 구하기
        /// </summary>
        /// <param name="degree">도</param>
        /// <returns>라디안</returns>
        private double GetRadian(double degree)
        {
            return Math.PI * degree / 180.0;
        }

        #endregion
        #region 원 그리기 - DrawCircle(graphics, pen, centerX, centerY, radius)

        /// <summary>
        /// 원 그리기
        /// </summary>
        /// <param name="graphics">그래픽스</param>
        /// <param name="pen">펜</param>
        /// <param name="centerX">중심 X 좌표</param>
        /// <param name="centerY">중심 Y 좌표</param>
        /// <param name="radius">반경</param>
        private void DrawCircle(Graphics graphics, Pen pen, int centerX, int centerY, int radius)
        {
            Rectangle rectangle = new Rectangle(centerX - radius, centerY - radius, radius * 2, radius * 2);

            graphics.DrawEllipse(pen, rectangle);
        }

        #endregion
        #region 오각형 그리기 - DrawPentagram(graphics, pointArray)

        /// <summary>
        /// 오각형 그리기
        /// </summary>
        /// <param name="graphics">그래픽스</param>
        /// <param name="pointArray">포인트 배열</param>
        private void DrawPentagram(Graphics graphics, Point[] pointArray)
        {
            Point startPoint = pointArray[0];

            int offset = 2;

            for(int i = 0; i < pointArray.Length; i++)
            {
                Point endPoint = pointArray[offset % 5];

                graphics.DrawLine(Pens.Red, startPoint, endPoint);

                startPoint = endPoint;

                offset += 2;
            }
        }

        #endregion
        #region 오각형 그리기 - DrawPentagram(graphics)

        /// <summary>
        /// 오각형 그리기
        /// </summary>
        /// <param name="graphics">그래픽스</param>
        private void DrawPentagram(Graphics graphics)
        {
            Point[] pointArray = new Point[5];

            int centerX = Width  / 2;
            int centerY = Height / 2;

            int radius = 200;

            DrawCircle(graphics, this.bluePen, centerX, centerY, radius);

            DrawCircle(graphics, this.redPen, centerX, centerY - radius, 10);

            double yPosition = Math.Cos(GetRadian(72)) * radius;

            int lastDegree = 90 - 72;

            double xPosition = Math.Cos(GetRadian(lastDegree)) * radius;

            DrawCircle(graphics, this.redPen, centerX - (int)xPosition, centerY - (int)yPosition, 10);

            pointArray[0] = new Point(centerX, centerY - radius);
            pointArray[1] = new Point(centerX - (int)xPosition, centerY - (int)yPosition);

            graphics.DrawLine(redPen, pointArray[0], pointArray[1]);

            xPosition = Math.Cos(GetRadian(72 - lastDegree)) * radius;

            lastDegree = 90 - (72 - lastDegree);

            yPosition = Math.Cos(GetRadian(lastDegree)) * radius;

            DrawCircle(graphics, redPen, centerX - (int)xPosition, centerY + (int)yPosition, 10);

            pointArray[2] = new Point(centerX - (int)xPosition, centerY + (int)yPosition);

            graphics.DrawLine(redPen, pointArray[1], pointArray[2]);

            yPosition = Math.Cos(GetRadian(72 - lastDegree)) * radius;

            xPosition = Math.Sin(GetRadian(lastDegree)) * radius;

            DrawCircle(graphics, redPen, centerX + (int)xPosition, centerY + (int)yPosition, 10);

            pointArray[3] = new Point(centerX + (int)xPosition, centerY + (int)yPosition);

            graphics.DrawLine(redPen, pointArray[2], pointArray[3]);

            lastDegree = 72 - (90 - lastDegree);

            xPosition = Math.Cos(GetRadian(lastDegree)) * radius;
            yPosition = Math.Sin(GetRadian(lastDegree)) * radius;

            DrawCircle(graphics, redPen, centerX + (int)xPosition, centerY - (int)yPosition, 10);

            pointArray[4] = new Point(centerX + (int)xPosition, centerY - (int)yPosition);

            graphics.DrawLine(redPen, pointArray[3], pointArray[4]);

            graphics.DrawLine(redPen, pointArray[4], pointArray[0]);

            DrawPentagram(graphics, pointArray);
        }

        #endregion
    }
}