Example #1
0
        protected override void OnPaint(PaintEventArgs pe)
        {
            //these settings aren't even needed for good perf, but they are helpful
            pe.Graphics.InterpolationMode  = InterpolationMode.Low;
            pe.Graphics.CompositingQuality = CompositingQuality.HighSpeed;
            pe.Graphics.SmoothingMode      = SmoothingMode.HighSpeed;

            if (image != null)
            {
                //draw empty area, if it exists, in an optimized way.
                if (AutoScrollPosition.X == 0)
                {
                    int emptyRightAreaWidth = Width - image.Bitmap.Width;
                    if (emptyRightAreaWidth > 0)
                    {
                        Rectangle fillRect = new Rectangle(image.Bitmap.Width, 0, emptyRightAreaWidth, Height);
                        fillRect.Intersect(pe.ClipRectangle);
                        pe.Graphics.FillRectangle(SystemBrushes.Control, fillRect);
                    }
                }

                if (AutoScrollPosition.Y == 0)
                {
                    int emptyRightAreaHeight = Height - image.Bitmap.Height;
                    if (emptyRightAreaHeight > 0)
                    {
                        Rectangle fillRect = new Rectangle(0, image.Bitmap.Height, Width, emptyRightAreaHeight);
                        fillRect.Intersect(pe.ClipRectangle);
                        pe.Graphics.FillRectangle(SystemBrushes.Control, fillRect);
                    }
                }

                //calculate the visible area of the bitmap
                Rectangle bitmapRect        = new Rectangle(AutoScrollPosition.X, AutoScrollPosition.Y, image.Bitmap.Width, image.Bitmap.Height);
                Rectangle visibleClientRect = bitmapRect;
                visibleClientRect.Intersect(pe.ClipRectangle);
                if (visibleClientRect.Width == 0 || visibleClientRect.Height == 0)
                {
                    return;
                }
                Rectangle visibleBitmapRect = visibleClientRect;
                visibleBitmapRect.Offset(-AutoScrollPosition.X, -AutoScrollPosition.Y);

                //draw bitmap
                if (newMethod)
                {
                    using (EditableBitmap section = image.CreateView(visibleBitmapRect))
                        pe.Graphics.DrawImageUnscaled(section.Bitmap, visibleClientRect.Location);
                }
                else //normal method
                {
                    pe.Graphics.DrawImage(image.Bitmap, visibleClientRect, visibleBitmapRect, GraphicsUnit.Pixel);
                }
            }
            else //if no bitmap just fill with background color
            {
                pe.Graphics.FillRectangle(SystemBrushes.Control, pe.ClipRectangle);
            }
        }
Example #2
0
        protected void Dispose(bool disposing)
        {
            if (disposed)
            {
                return;
            }

            bitmap.Dispose();
            byteArray.ReleaseReference();
            disposed = true;

            //Set managed object refs to null if explicitly disposing, so that they can be cleaned up by the GC.
            if (disposing)
            {
                owner  = null;
                bitmap = null;
            }
        }
Example #3
0
        /// <summary>
        /// Creates an <see cref="EditableBitmap"/> as a view on a section of an existing <see cref="EditableBitmap"/>.
        /// </summary>
        /// <param name="source"></param>
        /// <param name="viewArea"></param>
        protected EditableBitmap(EditableBitmap source, Rectangle viewArea)
        {
            owner           = source;
            pixelFormatSize = source.pixelFormatSize;
            byteArray       = source.byteArray;
            byteArray.AddReference();
            stride = source.stride;

            try
            {
                startOffset = source.startOffset + (stride * viewArea.Y) + (viewArea.X * pixelFormatSize);
                bitmap      = new Bitmap(viewArea.Width, viewArea.Height, stride, source.Bitmap.PixelFormat,
                                         (IntPtr)(((int)byteArray.bitPtr) + startOffset));
            }
            finally
            {
                if (bitmap == null)
                {
                    byteArray.ReleaseReference();
                }
            }
        }