public PixelReference(Map parent, int row, int column) { this._parent = parent; _ncolors = parent.BytesPerPixel; _offset = (parent.RowOffset(row) + column) * _ncolors; _blueOffset = parent.BlueOffset; _greenOffset = parent.GreenOffset; _redOffset = parent.RedOffset; }
public PixelReference(Map parent, int row, int column) { this._parent = parent; _ncolors = parent.BytesPerPixel; _offset = (parent.RowOffset(row) + column) * _ncolors; _blueOffset = parent.BlueOffset; _greenOffset = parent.GreenOffset; _redOffset = parent.RedOffset; }
/// <summary> Fill this image from another source at reduced resolution. Pixel /// averaging will be used. /// /// </summary> /// <param name="src">image map to reduce /// </param> /// <param name="subsample">rate to subsample /// </param> /// <param name="pdr">target bounds /// </param> public virtual void Downsample(Map src, int subsample, Rectangle pdr) { Rectangle rect = new Rectangle(0, 0, ((src.ImageWidth + subsample) - 1) / subsample, ((src.ImageHeight + subsample) - 1) / subsample); if (pdr != null) { if ((pdr.Right < rect.Right) || (pdr.Bottom < rect.Bottom) || (pdr.Left > rect.Left) || (pdr.Top > rect.Top)) { throw new ArgumentException("Specified rectangle overflows destination PixelMap"); } rect = pdr; } Init(rect.Height, rect.Width, null); int sy = rect.Bottom * subsample; int sxz = rect.Right * subsample; int sidx = src.RowOffset(sy); int didx = 0; PixelReference sptr = src.CreateGPixelReference(0); PixelReference dptr = CreateGPixelReference(0); for (int y = 0; y < ImageHeight; y++) { int sx = sxz; for (int x = ImageWidth; x-- > 0; dptr.IncOffset()) { int r = 0; int g = 0; int b = 0; int s = 0; int kidx = sidx; int lsy = sy + subsample; if (lsy > src.ImageHeight) { lsy = src.ImageHeight; } int lsx = sx + subsample; if (lsx > src.ImageWidth) { lsx = src.ImageWidth; } for (int rsy = sy; rsy < lsy; rsy++) { sptr.SetOffset(kidx + sx); if (!IsRampNeeded) { for (int rsx = lsx - sx; rsx-- > 0; sptr.IncOffset()) { r += sptr.Red; g += sptr.Green; b += sptr.Blue; s++; } } else { for (int rsx = lsx - sx; rsx-- > 0; sptr.IncOffset()) { Pixel pix = src.PixelRamp(sptr); r += pix.Red; g += pix.Green; b += pix.Blue; s++; } } kidx += src.GetRowSize(); } if (s >= _invmap.Length) { dptr.SetBGR(b / s, g / s, r / s); } else { dptr.SetBGR(((b * _invmap[s]) + 32768) >> 16, ((g * _invmap[s]) + 32768) >> 16, ((r * _invmap[s]) + 32768) >> 16); } sx += subsample; } sy += subsample; sidx += src.RowOffset(subsample); dptr.SetOffset(didx += GetRowSize()); } }
/// <summary> Set the map image pixel we are refering to. /// /// </summary> /// <param name="row">vertical position /// </param> /// <param name="column">horizontal position /// </param> public void SetOffset(int row, int column) { _offset = (_parent.RowOffset(row) + column) * _ncolors; }
/// <summary> Fill this image from another source at reduced resolution. Pixel /// averaging will be used. /// /// </summary> /// <param name="src">image map to reduce /// </param> /// <param name="subsample">rate to subsample /// </param> /// <param name="pdr">target bounds /// </param> public virtual void Downsample(Map src, int subsample, Rectangle pdr) { Rectangle rect = new Rectangle(0, 0, ((src.ImageWidth + subsample) - 1) / subsample, ((src.ImageHeight + subsample) - 1) / subsample); if (pdr != null) { if ((pdr.Right < rect.Right) || (pdr.Bottom < rect.Bottom) || (pdr.Left > rect.Left) || (pdr.Top > rect.Top)) { throw new ArgumentException("Specified rectangle overflows destination PixelMap"); } rect = pdr; } Init(rect.Height, rect.Width, null); int sy = rect.Bottom * subsample; int sxz = rect.Right * subsample; int sidx = src.RowOffset(sy); int didx = 0; PixelReference sptr = src.CreateGPixelReference(0); PixelReference dptr = CreateGPixelReference(0); for (int y = 0; y < ImageHeight; y++) { int sx = sxz; for (int x = ImageWidth; x-- > 0; dptr.IncOffset()) { int r = 0; int g = 0; int b = 0; int s = 0; int kidx = sidx; int lsy = sy + subsample; if (lsy > src.ImageHeight) { lsy = src.ImageHeight; } int lsx = sx + subsample; if (lsx > src.ImageWidth) { lsx = src.ImageWidth; } for (int rsy = sy; rsy < lsy; rsy++) { sptr.SetOffset(kidx + sx); if (!IsRampNeeded) { for (int rsx = lsx - sx; rsx-- > 0; sptr.IncOffset()) { r += sptr.Red; g += sptr.Green; b += sptr.Blue; s++; } } else { for (int rsx = lsx - sx; rsx-- > 0; sptr.IncOffset()) { Pixel pix = src.PixelRamp(sptr); r += pix.Red; g += pix.Green; b += pix.Blue; s++; } } kidx += src.GetRowSize(); } if (s >= _invmap.Length) { dptr.SetBGR(b / s, g / s, r / s); } else { dptr.SetBGR(((b * _invmap[s]) + 32768) >> 16, ((g * _invmap[s]) + 32768) >> 16, ((r * _invmap[s]) + 32768) >> 16); } sx += subsample; } sy += subsample; sidx += src.RowOffset(subsample); dptr.SetOffset(didx += GetRowSize()); } }