Class.FastBitmap

/*******************************************************************************
 * FastBitmap.cs
 * A fast implementation of System.Drawing.Bitmap class.
 * -----------------------------------------------------------------------------
 * Project: DIG+ Image Library (ABANDONED)
 * Author: Conmajia
 * Url: conmajia@gmail.com
 * Initiate: 9th July, 2012
 * Version: 1.0.0.0
 * History:
 *      9th July, 2012
 *      Initiated.
 * ****************************************************************************/
using System;
using System.Collections.Generic;
using System.Text;
using System.Drawing.Imaging;
using System.Drawing;

namespace Conmajia.Drawing.Image
{
    /// <summary>
    /// 增强位图类。
    /// </summary>
    /// <remarks>
    /// 高性能 Bitmap 类。
    /// 为DIG+（数字智能游戏）项目设计，目前已废弃。
    /// By Conmajia
    /// </remarks>
    public class FastBitmap : IDisposable, ICloneable
    {
        #region 字段
        internal Bitmap _bitmap;
        BitmapData _bitmapData;
        #endregion

        #region 构造与析构
        private FastBitmap() { }

        public FastBitmap(Bitmap bitmap)
        {
            _bitmap = bitmap;
        }
        
        public FastBitmap(int width, int height, PixelFormat format)
        {
            _bitmap = new Bitmap(width, height, format);
        }

        ~FastBitmap()
        {
            Dispose(false);
        }

        public void Dispose()
        {
            GC.SuppressFinalize(this);
            Dispose(true);
        }

        protected virtual void Dispose(bool disposing)
        {
            Unlock();
            if (disposing)
            {
                _bitmap.Dispose();
            }
        }
        #endregion

        #region 方法
        public object Clone()
        {
            FastBitmap clone = new FastBitmap();
            clone._bitmap = (Bitmap)_bitmap.Clone();
            return clone;
        }

        public int Width
        {
            get { return _bitmap.Width; }
        }

        public int Height
        {
            get { return _bitmap.Height; }
        }

        public void Lock()
        {
            _bitmapData = _bitmap.LockBits(
                new Rectangle(0, 0, _bitmap.Width, _bitmap.Height),
                ImageLockMode.ReadWrite,
                _bitmap.PixelFormat
                );
        }

        unsafe public Color GetPixel(int x, int y)
        {
            if (_bitmapData.PixelFormat == PixelFormat.Format32bppArgb)
            {
                byte* b = (byte*)_bitmapData.Scan0 + (y * _bitmapData.Stride) + (x * 4);
                return Color.FromArgb(*(b + 3), *(b + 2), *(b + 1), *b);
            }
            else if (_bitmapData.PixelFormat == PixelFormat.Format24bppRgb)
            {
                byte* b = (byte*)_bitmapData.Scan0 + (y * _bitmapData.Stride) + (x * 3);
                return Color.FromArgb(*(b + 2), *(b + 1), *b);
            }
            return Color.Empty;
        }

        unsafe public void SetPixel(int x, int y, Color c)
        {
            if (_bitmapData.PixelFormat == PixelFormat.Format32bppArgb)
            {
                byte* b = (byte*)_bitmapData.Scan0 + (y * _bitmapData.Stride) + (x * 4);
                *b = c.B;
                *(b + 1) = c.G;
                *(b + 2) = c.R;
                *(b + 3) = c.A;
            }
            else if (_bitmapData.PixelFormat == PixelFormat.Format24bppRgb)
            {
                byte* b = (byte*)_bitmapData.Scan0 + (y * _bitmapData.Stride) + (x * 3);
                *b = c.B;
                *(b + 1) = c.G;
                *(b + 2) = c.R;
            }
        }

        public Byte GetIntensity(int x, int y)
        {
            Color c = GetPixel(x, y);
            return (byte)((c.R * 0.30 + c.G * 0.59 + c.B * 0.11) + 0.5);
        }

        public void Unlock()
        {
            if (_bitmapData != null)
            {
                _bitmap.UnlockBits(_bitmapData);
                _bitmapData = null;
            }
        }

        public void Save(string filename, ImageFormat format)
        {
            _bitmap.Save(filename, format);
        }

        public void Save(string filename)
        {
            _bitmap.Save(filename);
        }
        #endregion
    }
}