C# ShapeCollection.Clear方法代码示例

        /// <summary>
        /// Modifies the first Polygon so that it is the result of both merged polygons.  
        /// This method assumes that the polygons collide and that both are drawn
        /// clockwise.
        /// </summary>
        /// <param name="polygon">The first polygon.  This one will be modified.</param>
        /// <param name="otherPolygon">The second polygon which will not be modified.</param>
        #endregion
        public static void Merge(Polygon polygon, Polygon otherPolygon)
        {
            // Vic says:  This is useful for debugging merging.  Don't remove it!!!
            bool shouldDebug = false;
            Segment[] firstSegments;
            Segment[] secondSegments;
            List<ContactPoint> contactPoints = GetContactPoints(polygon, otherPolygon, out firstSegments, out secondSegments);

#if !SILVERLIGHT && !WINDOWS_PHONE && !XBOX360 && !IOS && !MONODROID

            if (shouldDebug)
            {
                ShapeCollection sc = new ShapeCollection();
                sc.Polygons.Add(polygon);
                sc.Polygons.Add(otherPolygon);

                for (int i = 0; i < contactPoints.Count; i++)
                {
                    Circle circle = new Circle();
                    circle.Radius = .5f;
                    circle.Position = contactPoints[i].Position;

                    if (contactPoints[i].ContactType == ContactType.SegmentIntersection)
                    {
                        circle.Color = Color.Orange;
                    }
                    else
                    {
                        circle.Color = Color.Green;
                    }

                    sc.Circles.Add(circle);

                }



                FlatRedBall.Content.Math.Geometry.ShapeCollectionSave scs =
                    new FlatRedBall.Content.Math.Geometry.ShapeCollectionSave();

                scs.AddPolygonList(sc.Polygons);
                scs.AddCircleList(sc.Circles);

                string fileName = 
                    FlatRedBall.IO.FileManager.MyDocuments + "mergeTest.shcx";

                scs.Save(fileName);

                sc.Clear();
            }
#endif

            int firstPointToStartAt = GetPointToStartAt(polygon, otherPolygon);

            if (firstPointToStartAt == -1)
            {
                throw new NotImplementedException();
                // return a polygon that is the same shape as the rectangle
            }

            List<Vector3> thisVertices = GetAbsoluteVertices(firstSegments);
            List<Vector3> otherVertices = GetAbsoluteVertices(secondSegments);

            SetPointsFromContactPointsAndVertices(polygon, otherPolygon, contactPoints, firstPointToStartAt, thisVertices, otherVertices);
        }

//.........这里部分代码省略.........
                switch (imageFormat) {
                    case ImageFileFormat.Svg:
                        throw new NotImplementedException();

                    case ImageFileFormat.Emf:
                    case ImageFileFormat.EmfPlus:
                        // Create MetaFile and graphics context
                        IntPtr hdc = infoGraphics.GetHdc();
                        try {
                            Rectangle bounds = Rectangle.Empty;
                            bounds.Size = imageBounds.Size;
                            result = new Metafile(hdc, bounds, MetafileFrameUnit.Pixel,
                                                (imageFormat == ImageFileFormat.Emf) ? EmfType.EmfOnly : EmfType.EmfPlusDual,
                                                Name);
                        } finally {
                            infoGraphics.ReleaseHdc(hdc);
                        }
                        break;

                    case ImageFileFormat.Bmp:
                    case ImageFileFormat.Gif:
                    case ImageFileFormat.Jpeg:
                    case ImageFileFormat.Png:
                    case ImageFileFormat.Tiff:
                        int imgWidth = imageBounds.Width;
                        int imgHeight = imageBounds.Height;
                        if (dpi > 0 && dpi != infoGraphics.DpiX || dpi != infoGraphics.DpiY) {
                            scaleX = dpi / infoGraphics.DpiX;
                            scaleY = dpi / infoGraphics.DpiY;
                            imgWidth = (int)Math.Round(scaleX * imageBounds.Width);
                            imgHeight = (int)Math.Round(scaleY * imageBounds.Height);
                        }
                        result = new Bitmap(Math.Max(1, imgWidth), Math.Max(1, imgHeight));
                        ((Bitmap)result).SetResolution(dpi, dpi);
                        break;

                    default:
                        throw new NShapeUnsupportedValueException(typeof(ImageFileFormat), imageFormat);
                }

                // Draw diagram
                using (Graphics gfx = Graphics.FromImage(result)) {
                    GdiHelpers.ApplyGraphicsSettings(gfx, RenderingQuality.MaximumQuality);

                    // Fill background with background color
                    if (backgroundColor.A < 255) {
                        if (imageFormat == ImageFileFormat.Bmp || imageFormat == ImageFileFormat.Jpeg) {
                            // For image formats that do not support transparency, fill background with the RGB part of
                            // the given backgropund color
                            gfx.Clear(Color.FromArgb(255, backgroundColor));
                        } else if (backgroundColor.A > 0) {
                            // Skip filling background for meta files if transparency is 100%:
                            // Filling Background with Color.Transparent causes graphical glitches with many applications
                            gfx.Clear(backgroundColor);
                        }
                    } else {
                        // Graphics.Clear() does not work as expected for classic EMF (fills only the top left pixel
                        // instead of the whole graphics context).
                        if (imageFormat == ImageFileFormat.Emf) {
                            using (SolidBrush brush = new SolidBrush(backgroundColor))
                                gfx.FillRectangle(brush, gfx.ClipBounds);
                        } else gfx.Clear(backgroundColor);
                    }

                    // Transform graphics (if necessary)
                    gfx.TranslateTransform(-imageBounds.X, -imageBounds.Y, MatrixOrder.Prepend);
                    if (scaleX != 1 || scaleY != 1) gfx.ScaleTransform(scaleX, scaleY, MatrixOrder.Append);

                    // Draw diagram background
                    if (withBackground) DrawBackground(gfx, imageBounds);
                    // Draw diagram shapes
                    if (shapes == null) {
                        foreach (Shape shape in diagramShapes.BottomUp) shape.Draw(gfx);
                    } else {
                        // Add shapes to ShapeCollection (in order to maintain zOrder while drawing)
                        int cnt = (shapes is ICollection) ? ((ICollection)shapes).Count : -1;
                        ShapeCollection shapeCollection = new ShapeCollection(cnt);
                        foreach (Shape s in shapes) {
                            // Sort out duplicate references to shapes (as they can occur in the result of Diagram.FindShapes())
                            if (shapeCollection.Contains(s)) continue;
                            shapeCollection.Add(s, s.ZOrder);
                        }
                        // Draw shapes
                        foreach (Shape shape in shapeCollection.BottomUp)
                            shape.Draw(gfx);
                        shapeCollection.Clear();
                    }
                    // Reset transformation
                    gfx.ResetTransform();
                }
                // Restore original graphics settings
                HighQualityRendering = originalQualitySetting;
                UpdateBrushes();

                return result;
            } finally {
                if (disposeInfoGfx)
                    GdiHelpers.DisposeObject(ref infoGraphics);
            }
        }