protected override unsafe void BicubicFitSurfaceChecked(SurfaceBase source, Rectangle dstRoi) { Rectangle roi = Rectangle.Intersect(dstRoi, Bounds); IntPtr rColCacheIP = ImageSurfaceMemory.Allocate(4 * (ulong)roi.Width * (ulong)sizeof(double)); double *rColCache = (double *)rColCacheIP.ToPointer(); int srcWidth = source.Width; int srcHeight = source.Height; long srcStride = source.Stride; // Precompute and then cache the value of R() for each column for (int dstX = roi.Left; dstX < roi.Right; ++dstX) { double srcColumn = (double)(dstX * (srcWidth - 1)) / (double)(width - 1); double srcColumnFloor = Math.Floor(srcColumn); double srcColumnFrac = srcColumn - srcColumnFloor; for (int m = -1; m <= 2; ++m) { int index = (m + 1) + ((dstX - roi.Left) * 4); double x = m - srcColumnFrac; rColCache[index] = BicubicUtil.R(x); } } // Set this up so we can cache the R()'s for every row double *rRowCache = stackalloc double[4]; for (int dstY = roi.Top; dstY < roi.Bottom; ++dstY) { double srcRow = (double)(dstY * (srcHeight - 1)) / (double)(height - 1); double srcRowFloor = (double)Math.Floor(srcRow); double srcRowFrac = srcRow - srcRowFloor; int srcRowInt = (int)srcRow; ColorBgra16 *dstPtr = (ColorBgra16 *)GetPointAddressUnchecked(roi.Left, dstY); // Compute the R() values for this row for (int n = -1; n <= 2; ++n) { double x = srcRowFrac - n; rRowCache[n + 1] = BicubicUtil.R(x); } // See Perf Note below //int nFirst = Math.Max(-srcRowInt, -1); //int nLast = Math.Min(source.height - srcRowInt - 1, 2); for (int dstX = roi.Left; dstX < roi.Right; dstX++) { double srcColumn = (double)(dstX * (srcWidth - 1)) / (double)(width - 1); double srcColumnFloor = Math.Floor(srcColumn); int srcColumnInt = (int)srcColumn; double blueSum = 0; double greenSum = 0; double redSum = 0; double alphaSum = 0; double totalWeight = 0; // See Perf Note below //int mFirst = Math.Max(-srcColumnInt, -1); //int mLast = Math.Min(source.width - srcColumnInt - 1, 2); ColorBgra16 *srcPtr = (ColorBgra16 *)source.GetPointAddressUnchecked(srcColumnInt - 1, srcRowInt - 1); for (int n = -1; n <= 2; ++n) { int srcY = srcRowInt + n; for (int m = -1; m <= 2; ++m) { // Perf Note: It actually benchmarks faster on my system to do // a bounds check for every (m,n) than it is to limit the loop // to nFirst-Last and mFirst-mLast. // I'm leaving the code above, albeit commented out, so that // benchmarking between these two can still be performed. if (source.IsVisible(srcColumnInt + m, srcY)) { double w0 = rColCache[(m + 1) + (4 * (dstX - roi.Left))]; double w1 = rRowCache[n + 1]; double w = w0 * w1; blueSum += srcPtr->B * w * srcPtr->A; greenSum += srcPtr->G * w * srcPtr->A; redSum += srcPtr->R * w * srcPtr->A; alphaSum += srcPtr->A * w; totalWeight += w; } ++srcPtr; } srcPtr = (ColorBgra16 *)((byte *)(srcPtr - 4) + srcStride); } double alpha = alphaSum / totalWeight; double blue; double green; double red; if (alpha == 0) { blue = 0; green = 0; red = 0; } else { blue = blueSum / alphaSum; green = greenSum / alphaSum; red = redSum / alphaSum; // add 0.5 to ensure truncation to ulong results in rounding alpha += 0.5; blue += 0.5; green += 0.5; red += 0.5; } dstPtr->Bgra = (ulong)blue + ((ulong)green << 16) + ((ulong)red << 32) + ((ulong)alpha << 48); ++dstPtr; } // for (dstX... } // for (dstY... ImageSurfaceMemory.Free(rColCacheIP); }
protected override unsafe void BicubicFitSurfaceUnchecked(SurfaceBase source, Rectangle dstRoi) { Rectangle roi = Rectangle.Intersect(dstRoi, Bounds); IntPtr rColCacheIP = ImageSurfaceMemory.Allocate(4 * (ulong)roi.Width * (ulong)sizeof(double)); double *rColCache = (double *)rColCacheIP.ToPointer(); int srcWidth = source.Width; int srcHeight = source.Height; long srcStride = source.Stride; // Precompute and then cache the value of R() for each column for (int dstX = roi.Left; dstX < roi.Right; ++dstX) { double srcColumn = (double)(dstX * (srcWidth - 1)) / (double)(width - 1); double srcColumnFloor = Math.Floor(srcColumn); double srcColumnFrac = srcColumn - srcColumnFloor; for (int m = -1; m <= 2; ++m) { int index = (m + 1) + ((dstX - roi.Left) * 4); double x = m - srcColumnFrac; rColCache[index] = BicubicUtil.R(x); } } // Set this up so we can cache the R()'s for every row double *rRowCache = stackalloc double[4]; for (int dstY = roi.Top; dstY < roi.Bottom; ++dstY) { double srcRow = (double)(dstY * (srcHeight - 1)) / (double)(height - 1); double srcRowFloor = Math.Floor(srcRow); double srcRowFrac = srcRow - srcRowFloor; int srcRowInt = (int)srcRow; ColorBgra16 *dstPtr = (ColorBgra16 *)GetPointAddressUnchecked(roi.Left, dstY); // Compute the R() values for this row for (int n = -1; n <= 2; ++n) { double x = srcRowFrac - n; rRowCache[n + 1] = BicubicUtil.R(x); } rColCache = (double *)rColCacheIP.ToPointer(); ColorBgra16 *srcRowPtr = (ColorBgra16 *)source.GetRowAddressUnchecked(srcRowInt - 1); for (int dstX = roi.Left; dstX < roi.Right; dstX++) { double srcColumn = (double)(dstX * (srcWidth - 1)) / (double)(width - 1); double srcColumnFloor = Math.Floor(srcColumn); int srcColumnInt = (int)srcColumn; double blueSum = 0; double greenSum = 0; double redSum = 0; double alphaSum = 0; double totalWeight = 0; ColorBgra16 *srcPtr = srcRowPtr + srcColumnInt - 1; for (int n = 0; n <= 3; ++n) { double w0 = rColCache[0] * rRowCache[n]; double w1 = rColCache[1] * rRowCache[n]; double w2 = rColCache[2] * rRowCache[n]; double w3 = rColCache[3] * rRowCache[n]; double a0 = srcPtr[0].A; double a1 = srcPtr[1].A; double a2 = srcPtr[2].A; double a3 = srcPtr[3].A; alphaSum += (a0 * w0) + (a1 * w1) + (a2 * w2) + (a3 * w3); totalWeight += w0 + w1 + w2 + w3; blueSum += (a0 * srcPtr[0].B * w0) + (a1 * srcPtr[1].B * w1) + (a2 * srcPtr[2].B * w2) + (a3 * srcPtr[3].B * w3); greenSum += (a0 * srcPtr[0].G * w0) + (a1 * srcPtr[1].G * w1) + (a2 * srcPtr[2].G * w2) + (a3 * srcPtr[3].G * w3); redSum += (a0 * srcPtr[0].R * w0) + (a1 * srcPtr[1].R * w1) + (a2 * srcPtr[2].R * w2) + (a3 * srcPtr[3].R * w3); srcPtr = (ColorBgra16 *)((byte *)srcPtr + srcStride); } double alpha = alphaSum / totalWeight; double blue; double green; double red; if (alpha == 0) { blue = 0; green = 0; red = 0; } else { blue = blueSum / alphaSum; green = greenSum / alphaSum; red = redSum / alphaSum; // add 0.5 to ensure truncation to ulong results in rounding alpha += 0.5; blue += 0.5; green += 0.5; red += 0.5; } dstPtr->Bgra = (ulong)blue + ((ulong)green << 16) + ((ulong)red << 32) + ((ulong)alpha << 48); ++dstPtr; rColCache += 4; } // for (dstX... } // for (dstY... ImageSurfaceMemory.Free(rColCacheIP); }