Project/Assets/Standard Assets/Scripts/TextureExtension.cs

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

public static class TextureExtension
{
	public struct Point
	{
		public short x;
		public short y;
		public Point(short aX, short aY) { x = aX; y = aY; }
		public Point(int aX, int aY) : this((short)aX, (short)aY) { }
	}
	
	public static void FloodFillArea(this Texture2D aTex, int aX, int aY, Color aFillColor)
	{
		int w = aTex.width;
		int h = aTex.height;
		Color[] colors = aTex.GetPixels();
		Color refCol = colors[aX + aY * w];
		Queue<Point> nodes = new Queue<Point>();
		nodes.Enqueue(new Point(aX, aY));
		while (nodes.Count > 0)
		{
			Point current = nodes.Dequeue();
			for (int i = current.x; i < w; i++)
			{
				Color C = colors[i + current.y * w];
				if (C != refCol || C == aFillColor)
					break;
				colors[i + current.y * w] = aFillColor;
				if (current.y + 1 < h)
				{
					C = colors[i + current.y * w + w];
					if (C == refCol && C != aFillColor)
						nodes.Enqueue(new Point(i, current.y + 1));
				}
				if (current.y - 1 >= 0)
				{
					C = colors[i + current.y * w - w];
					if (C == refCol && C != aFillColor)
						nodes.Enqueue(new Point(i, current.y - 1));
				}
			}
			for (int i = current.x - 1; i >= 0; i--)
			{
				Color C = colors[i + current.y * w];
				if (C != refCol || C == aFillColor)
					break;
				colors[i + current.y * w] = aFillColor;
				if (current.y + 1 < h)
				{
					C = colors[i + current.y * w + w];
					if (C == refCol && C != aFillColor)
						nodes.Enqueue(new Point(i, current.y + 1));
				}
				if (current.y - 1 >= 0)
				{
					C = colors[i + current.y * w - w];
					if (C == refCol && C != aFillColor)
						nodes.Enqueue(new Point(i, current.y - 1));
				}
			}
		}
		aTex.SetPixels(colors);
	}
	
	public static void FloodFillBorder(this Texture2D aTex, int aX, int aY, Color aFillColor, Color aBorderColor)
	{
		int w = aTex.width;
		int h = aTex.height;
		Color[] colors = aTex.GetPixels();
		byte[] checkedPixels = new byte[colors.Length];
		Color refCol = aBorderColor;
		Queue<Point> nodes = new Queue<Point>();
		nodes.Enqueue(new Point(aX, aY));
		while (nodes.Count > 0)
		{
			Point current = nodes.Dequeue();
			
			for (int i = current.x; i < w; i++)
			{
				if (checkedPixels[i + current.y * w] > 0 || colors[i + current.y * w] == refCol)
					break;
				colors[i + current.y * w] = aFillColor;
				checkedPixels[i + current.y * w] = 1;
				if (current.y + 1 < h)
				{
					if (checkedPixels[i + current.y * w + w] == 0 && colors[i + current.y * w + w] != refCol)
						nodes.Enqueue(new Point(i, current.y + 1));
				}
				if (current.y - 1 >= 0)
				{
					if (checkedPixels[i + current.y * w - w] == 0 && colors[i + current.y * w - w] != refCol)
						nodes.Enqueue(new Point(i, current.y - 1));
				}
			}
			for (int i = current.x - 1; i >= 0; i--)
			{
				if (checkedPixels[i + current.y * w] > 0 || colors[i + current.y * w] == refCol)
					break;
				colors[i + current.y * w] = aFillColor;
				checkedPixels[i + current.y * w] = 1;
				if (current.y + 1 < h)
				{
					if (checkedPixels[i + current.y * w + w] == 0 && colors[i + current.y * w + w] != refCol)
						nodes.Enqueue(new Point(i, current.y + 1));
				}
				if (current.y - 1 >= 0)
				{
					if (checkedPixels[i + current.y * w - w] == 0 && colors[i + current.y * w - w] != refCol)
						nodes.Enqueue(new Point(i, current.y - 1));
				}
			}
		}
		aTex.SetPixels(colors);
	}
}