ComponentFactory.Krypton.Toolkit.RenderGlassHelpers.DrawBackGlassBasic C# (CSharp) Method

        private static RectangleF DrawBackGlassBasic(RectangleF drawRect,
                                                     Color color1,
                                                     Color color2,
                                                     Color glassColor1,
                                                     Color glassColor2,
                                                     float factorX,
                                                     float factorY,
                                                     VisualOrientation orientation,
                                                     Graphics g,
                                                     float glassPercent,
                                                     ref IDisposable memento)
        {
            // Cannot draw a zero length rectangle
            if ((drawRect.Width > 0) && (drawRect.Height > 0))
            {
                bool generate = true;
                MementoBackGlassBasic cache;

                // Access a cache instance and decide if cache resources need generating
                if ((memento == null) || !(memento is MementoBackGlassBasic))
                {
                    if (memento != null)
                        memento.Dispose();

                    cache = new MementoBackGlassBasic(drawRect, color1, color2,
                                                      glassColor1, glassColor2,
                                                      factorX, factorY,
                                                      orientation, glassPercent);
                    memento = cache;
                }
                else
                {
                    cache = (MementoBackGlassBasic)memento;
                    generate = !cache.UseCachedValues(drawRect, color1, color2,
                                                      glassColor1, glassColor2,
                                                      factorX, factorY,
                                                      orientation, glassPercent);
                }

                // Do we need to generate the contents of the cache?
                if (generate)
                {
                    // Dispose of existing values
                    cache.Dispose();

                    // Draw entire area in a solid color
                    cache.totalBrush = new SolidBrush(color1);

                    int length;

                    if (VerticalOrientation(orientation))
                        length = (int)(drawRect.Height * glassPercent);
                    else
                        length = (int)(drawRect.Width * glassPercent);

                    RectangleF glassRect;

                    // Create rectangles that covers the glassy area
                    switch (orientation)
                    {
                        case VisualOrientation.Left:
                            glassRect = new RectangleF(drawRect.X, drawRect.Y, length, drawRect.Height);
                            break;
                        case VisualOrientation.Right:
                            glassRect = new RectangleF(drawRect.Right - length, drawRect.Y, length, drawRect.Height);
                            break;
                        case VisualOrientation.Bottom:
                            glassRect = new RectangleF(drawRect.X, drawRect.Bottom - length, drawRect.Width, length);
                            break;
                        case VisualOrientation.Top:
                        default:
                            glassRect = new RectangleF(drawRect.X, drawRect.Y, drawRect.Width, length);
                            break;
                    }

                    // Gradient rectangle is always a little bigger to prevent tiling at edges
                    RectangleF glassGradientRect = new RectangleF(glassRect.X - 1, glassRect.Y - 1, glassRect.Width + 2, glassRect.Height + 2);

                    // Cannot draw a zero length rectangle
                    if ((glassGradientRect.Width > 0) && (glassGradientRect.Height > 0))
                    {
                        cache.glassBrush = new LinearGradientBrush(glassGradientRect, glassColor1, glassColor2, AngleFromOrientation(orientation));
                        cache.glassRect = glassRect;
                    }
                }

                g.FillRectangle(cache.totalBrush, drawRect);

                if (cache.glassBrush != null)
                {
                    g.FillRectangle(cache.glassBrush, cache.glassRect);
                    return cache.glassRect;
                }
            }

            return RectangleF.Empty;
        }