Axiom.Media.NearestResampler.Scale C# (CSharp) Method

		static public void Scale( PixelBox src, PixelBox dst, int elementSize )
		{
			// assert(src.format == dst.format);
			// srcdata stays at beginning, pdst is a moving pointer
			//byte* srcdata = (byte*)src.Data;
			//byte* pdst = (byte*)dst.Data;
			int dstOffset = 0;

			// sx_48,sy_48,sz_48 represent current position in source
			// using 16/48-bit fixed precision, incremented by steps
			ulong stepx = ( (ulong)src.Width << 48 ) / (ulong)dst.Width;
			ulong stepy = ( (ulong)src.Height << 48 ) / (ulong)dst.Height;
			ulong stepz = ( (ulong)src.Depth << 48 ) / (ulong)dst.Depth;

			// note: ((stepz>>1) - 1) is an extra half-step increment to adjust
			// for the center of the destination pixel, not the top-left corner
			ulong sz_48 = ( stepz >> 1 ) - 1;
			for ( uint z = (uint)dst.Front; z < dst.Back; z++, sz_48 += stepz )
			{
				uint srczoff = (uint)( sz_48 >> 48 ) * (uint)src.SlicePitch;

				ulong sy_48 = ( stepy >> 1 ) - 1;
				for ( uint y = (uint)dst.Top; y < dst.Bottom; y++, sy_48 += stepy )
				{
					uint srcyoff = (uint)( sy_48 >> 48 ) * (uint)src.RowPitch;

					ulong sx_48 = ( stepx >> 1 ) - 1;
					for ( uint x = (uint)dst.Left; x < dst.Right; x++, sx_48 += stepx )
					{
						Memory.Copy( src.Data, dst.Data, (int)( elementSize * ( (uint)( sx_48 >> 48 ) + srcyoff + srczoff ) ), dstOffset, elementSize );
						dstOffset += elementSize;
					}
					dstOffset += elementSize * dst.RowSkip;
				}
				dstOffset += elementSize * dst.SliceSkip;
			}
		}