C# Gdk.Rectangle.GetBottom方法代码示例

        private ColorBgra[] GetPixelsFromPoint(PointD point)
        {
            var doc = PintaCore.Workspace.ActiveDocument;
            var x = (int)point.X;
            var y = (int)point.Y;
            var size = SampleSize;
            var half = size / 2;

            // Short circuit for single pixel
            if (size == 1)
                return new ColorBgra[] { GetPixel (x, y) };

            // Find the pixels we need (clamp to the size of the image)
            var rect = new Gdk.Rectangle (x - half, y - half, size, size);
            rect.Intersect (new Gdk.Rectangle (Gdk.Point.Zero, doc.ImageSize));

            var pixels = new List<ColorBgra> ();

            for (int i = rect.Left; i <= rect.GetRight (); i++)
                for (int j = rect.Top; j <= rect.GetBottom (); j++)
                    pixels.Add (GetPixel (i, j));

            return pixels.ToArray ();
        }

		public static unsafe SurfaceDiff Create (ImageSurface original, ImageSurface updated_surf, bool force = false)
		{
			if (original.Width != updated_surf.Width || original.Height != updated_surf.Height) {
				// If the surface changed size, only throw an error if the user forced the use of a diff.
				if (force) {
					throw new InvalidOperationException ("SurfaceDiff requires surfaces to be same size.");
				} else {
					return null;
				}
			}

			// Cache some pinvokes
			var orig_width = original.Width;
			var orig_height = original.Height;

#if DEBUG_DIFF
			Console.WriteLine ("Original surface size: {0}x{1}", orig_width, orig_height);
			System.Diagnostics.Stopwatch timer = new System.Diagnostics.Stopwatch();
			timer.Start();
#endif

			// STEP 1 - Find the bounds of the changed pixels.
			var orig_ptr = (int*)original.DataPtr;
			var updated_ptr = (int*)updated_surf.DataPtr;

			DiffBounds diff_bounds = new DiffBounds (orig_width, orig_height);
			object diff_bounds_lock = new Object();

			// Split up the work among several threads, each of which processes one row at a time
			// and updates the bounds of the changed pixels it has seen so far. At the end, the
			// results from each thread are merged together to find the overall bounds of the changed
			// pixels.
			Parallel.For<DiffBounds>(0, orig_height, () => new DiffBounds (orig_width, orig_height),
                     		(row, loop, my_bounds) => {

					var offset = row * orig_width;
					var orig = orig_ptr + offset;
					var updated = updated_ptr + offset;
					bool change_in_row = false;

					for (int i = 0; i < orig_width; ++i) {
						if (*(orig++) != *(updated++)) {
							change_in_row = true;
							my_bounds.left = System.Math.Min(my_bounds.left, i);
							my_bounds.right = System.Math.Max(my_bounds.right, i);
						}				
					}

					if (change_in_row) {
						my_bounds.top = System.Math.Min(my_bounds.top, row);
						my_bounds.bottom = System.Math.Max(my_bounds.bottom, row);
					}

					return my_bounds;

			},	(my_bounds) => {
					lock (diff_bounds_lock) {
						diff_bounds.Merge (my_bounds);
					}
					return;
			});

			var bounds = new Gdk.Rectangle (diff_bounds.left, diff_bounds.top,
			                                diff_bounds.right - diff_bounds.left + 1,
			                                diff_bounds.bottom - diff_bounds.top + 1);

#if DEBUG_DIFF
			Console.WriteLine ("Truncated surface size: {0}x{1}", bounds.Width, bounds.Height);
#endif

			// STEP 2 - Create a bitarray of whether each pixel in the bounds has changed, and count
			// how many changed pixels we need to store.
			var bitmask = new BitArray (bounds.Width * bounds.Height);
			int index = 0;
			int num_changed = 0;

			int bottom = bounds.GetBottom ();
			int right = bounds.GetRight ();
			int bounds_x = bounds.X;
			int bounds_y = bounds.Y;

			for (int y = bounds_y; y <= bottom; ++y) {
				var offset = y * orig_width;
				var updated = updated_ptr + offset + bounds_x;
				var orig = orig_ptr + offset + bounds_x;

				for (int x = bounds_x; x <= right; ++x) {
					bool changed = *(orig++) != *(updated++);
					bitmask[index++] = changed;
					if (changed) {
						num_changed++;
					}
				}
			}			

			var savings = 100 - (float)num_changed / (float)(orig_width * orig_height) * 100;
#if DEBUG_DIFF
			Console.WriteLine ("Compressed bitmask: {0}/{1} = {2}%", num_changed, orig_height * orig_width, 100 - savings);
#endif

//.........这里部分代码省略.........