[函数名称]
哈哈镜效果函数 WriteableBitmap DistortingMirrorProcess(WriteableBitmap src, int x, int y)
[算法说明]
哈哈镜效果图像实际上是一种图像形变特效而已，对于这个特效，我们可以通过三角变换来实现。
1，对于哈哈镜效果变换，首先它有两个参数，原点坐标和特效影响因子。
对于图像中的像素点P(x,y)，假设原点坐标为X，Y，那么，根据三角函数变换可以得到：
当前像素P的相对坐标cX,cY:
////// Distorting mirror process. /// /// The source image. /// Origin of coordinates in x direction. /// Origin of coordinates in y direction. ///public static WriteableBitmap DistortingMirrorProcess(WriteableBitmap src, int x, int y)哈哈镜特效 { if (src != null) { int w = src.PixelWidth; int h = src.PixelHeight; WriteableBitmap srcImage = new WriteableBitmap(w, h); byte[] temp = src.PixelBuffer.ToArray(); byte[] tempMask = (byte[])temp.Clone(); int radius = 0; double theta = 0; int tX = 0; int tY = 0; int mapX = 0; int mapY = 0; int mapR=0; for (int j = 0; j < h; j++) { for (int i = 0; i < w; i++) { tX = i - x; tY = j - y; theta = Math.Atan2((double)tY, (double)tX); radius = (int)Math.Sqrt((double)(tX * tX + tY * tY)); mapR = (int)(Math.Sqrt((double)radius * 100)); mapX = x + (int)(mapR * Math.Cos(theta)); mapY = y + (int)(mapR * Math.Sin(theta)); temp[i * 4 + j * w * 4] = tempMask[mapX * 4 + mapY * w * 4]; temp[i * 4 + 1 + j * w * 4] = tempMask[mapX * 4 + 1 + mapY * w * 4]; temp[i * 4 + 2 + j * w * 4] = tempMask[mapX * 4 + 2 + mapY * w * 4]; } } Stream sTemp = srcImage.PixelBuffer.AsStream(); sTemp.Seek(0, SeekOrigin.Begin); sTemp.Write(temp, 0, w * 4 * h); return srcImage; } else { return null; } }
[图像效果]
