[C#/WINFORM] 비교차 스타 그리기

TestProject.zip

다운로드

▶ MainForm.cs

using System;
using System.Drawing;
using System.Drawing.Drawing2D;
using System.Windows.Forms;

namespace TestProject
{
    /// <summary>
    /// 메인 폼
    /// </summary>
    public partial class MainForm : Form
    {
        //////////////////////////////////////////////////////////////////////////////////////////////////// Constructor
        ////////////////////////////////////////////////////////////////////////////////////////// Public

        #region 생성자 - MainForm()

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

            ResizeRedraw = true;

            #region 이벤트를 설정한다.

            Paint += Form_Paint;

            #endregion
        }

        #endregion

        //////////////////////////////////////////////////////////////////////////////////////////////////// Method
        ////////////////////////////////////////////////////////////////////////////////////////// Private
        //////////////////////////////////////////////////////////////////////////////// Event

        #region 폼 페인트시 처리하기 - Form_Paint(sender, e)

        /// <summary>
        /// 폼 페인트시 처리하기
        /// </summary>
        /// <param name="sender">이벤트 발생자</param>
        /// <param name="e">이벤트 인자</param>
        private void Form_Paint(object sender, PaintEventArgs e)
        {
            e.Graphics.SmoothingMode = SmoothingMode.AntiAlias;

            int width  = (int)(ClientRectangle.Width  * 0.9);
            int height = (int)(ClientRectangle.Height * 0.9);

            int size = (width > height) ? height : width;

            Rectangle rectangle = new Rectangle((int)((ClientRectangle.Width - size) / 2d), (int)((ClientRectangle.Height - size) / 2d), size, size);

            PointF[] pointArray = GetStarPointArray(5, rectangle);

            e.Graphics.DrawPolygon(Pens.Blue, pointArray);

            e.Graphics.DrawRectangle(Pens.Red, rectangle);
        }

        #endregion

        //////////////////////////////////////////////////////////////////////////////// Function

        #region 스타 포인트 배열 구하기 - GetStarPointArray(vertexCount, boundRectangle)

        /// <summary>
        /// 스타 포인트 배열 구하기
        /// </summary>
        /// <param name="vertexCount">꼭지점 카운트</param>
        /// <param name="boundRectangle">테두리 사각형</param>
        /// <returns>스타 포인트 배열</returns>
        private PointF[] GetStarPointArray(int vertexCount, Rectangle boundRectangle)
        {
            PointF[] pointArray = new PointF[2 * vertexCount];

            double rx1 = boundRectangle.Width / 2;
            double ry1 = boundRectangle.Height / 2;
            double rx2 = rx1 * 0.5;
            double ry2 = ry1 * 0.5;
            double cx  = boundRectangle.X + rx1;
            double cy  = boundRectangle.Y + ry1;

            double theta  = -Math.PI / 2;
            double dtheta = Math.PI / vertexCount;

            for(int i = 0; i < 2 * vertexCount; i += 2)
            {
                pointArray[i] = new PointF
                (
                    (float)(cx + rx1 * Math.Cos(theta)),
                    (float)(cy + ry1 * Math.Sin(theta))
                );

                theta += dtheta;

                pointArray[i + 1] = new PointF
                (
                    (float)(cx + rx2 * Math.Cos(theta)),
                    (float)(cy + ry2 * Math.Sin(theta))
                );

                theta += dtheta;
            }

            return pointArray;
        }

        #endregion
    }
}