C#，计算几何，计算机图形学（Computer Graphics）洪水填充算法（Flood Fill Algorithm）与源代码

1 泛洪填充算法(Flood Fill Algorithm)

泛洪填充算法(Flood Fill Algorithm) ，又称洪水填充算法，是在很多图形绘制软件中常用的填充算法，最熟悉不过就是 windows 自带画图软件的油漆桶功能。

2 源程序

using System;

using System.Collections;

using System.Collections.Generic;

namespace Legalsoft.Truffer.Algorithm

{

/// <summary>

/// 洪水填充算法

/// </summary>

public static partial class Algorithm_Gallery

{

private static void Fill_4Directions(int $,$ screen, int x, int y, int prevC, int newC)

{

int M = screen.GetLength(0);

int N = screen.GetLength(1);

if (x < 0 || x >= M || y < 0 || y >= N)

{

return;

}

if (screen $x, y$ != prevC)

{

return;

}

screen $x, y$ = newC;

Fill_4Directions(screen, x + 1, y, prevC, newC);

Fill_4Directions(screen, x - 1, y, prevC, newC);

Fill_4Directions(screen, x, y + 1, prevC, newC);

Fill_4Directions(screen, x, y - 1, prevC, newC);

}

public static void Flood_Fill(int $,$ screen, int x, int y, int newC)

{

int prevC = screen $x, y$ ;

if (prevC == newC)

{

return;

}

Fill_4Directions(screen, x, y, prevC, newC);

}

3 代码格式

cs 复制代码

using System;
using System.Collections;
using System.Collections.Generic;

namespace Legalsoft.Truffer.Algorithm
{
    /// <summary>
    /// 洪水填充算法
    /// </summary>
    public static partial class Algorithm_Gallery
    {
        private static void Fill_4Directions(int[,] screen, int x, int y, int prevC, int newC)
        {
            int M = screen.GetLength(0);
            int N = screen.GetLength(1);

            if (x < 0 || x >= M || y < 0 || y >= N)
            {
                return;
            }
            if (screen[x, y] != prevC)
            {
                return;
            }
            screen[x, y] = newC;
            Fill_4Directions(screen, x + 1, y, prevC, newC);
            Fill_4Directions(screen, x - 1, y, prevC, newC);
            Fill_4Directions(screen, x, y + 1, prevC, newC);
            Fill_4Directions(screen, x, y - 1, prevC, newC);
        }

        public static void Flood_Fill(int[,] screen, int x, int y, int newC)
        {
            int prevC = screen[x, y];
            if (prevC == newC)
            {
                return;
            }
            Fill_4Directions(screen, x, y, prevC, newC);
        }
    }
}