C# -- GraphicsPath.Flatten() 사용하기

C# -- GraphicsPath.Flatten() 사용하기

참고 : https://docs.microsoft.com/ko-kr/dotnet/api/system.drawing.drawing2d.graphicspath.flatten?view=netframework-4.7.2

        https://www.c-sharpcorner.com/UploadFile/mahesh/understanding-and-using-graphics-paths-in-gdi/

GraphicsPath.Flatten (System.Drawing.Drawing2D.Matrix matrix, float flatness);

flatness 

-- 곡선과 flattend 근사값 사이의 최대 허용 오차.

-- default = 0.25

-- 값이 작을수록, line segment 갯수가 증가함.

< 참고 >

Matrix.Translate (float offsetX, float offsetY)

https://docs.microsoft.com/ko-kr/dotnet/api/system.drawing.drawing2d.matrix.translate?view=netframework-4.7.2

-- 예 --

Matrix.Translate(100, 0)  --> x 축으로 100 이동

Matrix.Translate(0, 100)  --> y 축으로 100 이동

Matrix.Translate(100, 100)  --> x, y 축으로각각 100 이동

  https://docs.microsoft.com/ko-kr/dotnet/api/system.drawing.drawing2d.graphicspath.transform?view=netframework-4.7.2

      --> Matrix 사용법

      

< 결과 >

< 소스 >

--

	using System;
	using System.Collections.Generic;
	using System.ComponentModel;
	using System.Data;
	using System.Drawing;
	using System.Drawing.Drawing2D;
	using System.Linq;
	using System.Text;
	using System.Threading.Tasks;
	using System.Windows.Forms;
	namespace graphicspath_test1
	{
	public partial class Form1 : Form
	{
	public Form1()
	{
	InitializeComponent();
	}
	private void Form1_Load(object sender, EventArgs e)
	{
	}
	private void Form1_Paint(object sender, PaintEventArgs e)
	{
	var g = e.Graphics;
	Point[] points =
	{
	new Point(40,200),
	new Point(80,300),
	new Point(120,250),
	new Point(80,200),
	new Point(120,150),
	new Point(80,100)
	};
	using (GraphicsPath gPath = new GraphicsPath())
	using (Pen pen = new Pen(Color.Red, 3))
	{
	Matrix mx = new Matrix();
	mx.Translate(0, 20f); // y축으로 20 이동
	Matrix mx2 = new Matrix();
	mx2.Translate(20, 20f); // x축, y축으로 각각 20 이동
	gPath.AddCurve(points); // 곡선
	g.DrawPath(pen, gPath);
	pen.Color = Color.Green;
	gPath.Flatten(mx); // flatness default = 0.25
	g.DrawPath(pen, gPath);
	gPath.Reset(); // 기존 data 삭제
	pen.Color = Color.Blue;
	gPath.AddLines(points); // 직선
	g.DrawPath(pen, gPath);
	for(int i= 0; i < points.Length; i++)
	{
	points[i].Offset(150, 0); // x 축으로 150 이동
	}
	gPath.Reset(); // 기존 data 삭제
	pen.Color = Color.Red;
	gPath.AddCurve(points);
	g.DrawPath(pen, gPath);
	pen.Color = Color.Green;
	gPath.Flatten(mx2, 5); // flatness = 5
	g.DrawPath(pen, gPath);
	for (int i = 0; i < points.Length; i++)
	{
	points[i].Offset(150, 0); // x 축으로 150 이동
	}
	gPath.Reset(); // 기존 data 삭제
	gPath.AddCurve(points);
	gPath.Flatten(mx, 10); // flatness = 10
	g.DrawPath(pen, gPath);
	for (int i = 0; i < points.Length; i++)
	{
	points[i].Offset(150, 0); // x 축으로 150 이동
	}
	gPath.Reset(); // 기존 data 삭제
	gPath.AddCurve(points);
	gPath.Flatten(mx, 20); // flatness = 20
	g.DrawPath(pen, gPath);
	}
	}
	}
	}

view raw graphicspath_flatten_test.cs hosted with ❤ by GitHub