利用WPF绘制轮廓并保存为图片

1.前言

WPF作为显示工具也挺好用，用C#开发应用软件会比较省力，当然也有其缺点，如在对效率要求较高的情况下有性能问题，本文记录用WPF绘制轮廓并保存为图片相关内容。

显示效果也还不错，满足调试使用了，

2.代码

private static void DrawCurve(DrawingContext drawingContext, Pen pen, ICurve iCurve){if(iCurve is HLine2d){var point0 = iCurve.GetEndPoint(0);var point1 = iCurve.GetEndPoint(1);drawingContext.DrawLine(pen, new Point(point0.X, point0.Y), new Point(point1.X, point1.Y));}else if(iCurve is HArc2d){var point0 = iCurve.GetEndPoint(0);var point1 = iCurve.GetEndPoint(1);var pt0 = new Point(point0.X, point0.Y);var pt1 = new Point(point1.X, point1.Y);var hArc = iCurve as HArc2d;Point center = new Point(hArc.Center.X, hArc.Center.Y);bool bLarge = hArc.Large;bool bClockWise = !hArc.ClockWise;  //窗体坐标系为左手double radius = hArc.Radius;PathFigure figure = new PathFigure() { StartPoint = pt0, IsFilled = false };PathGeometry path = new PathGeometry();path.Figures.Add(figure);SweepDirection dirSweep = bClockWise ? SweepDirection.Clockwise : SweepDirection.Counterclockwise;ArcSegment line = new ArcSegment(pt1, new Size(radius, radius), 0.0, bLarge, dirSweep, true);figure.Segments.Add(line);drawingContext.DrawGeometry(null, pen, path);}}

public static System.Drawing.Bitmap ConvertPatternToBitmap2(List<ICurve> lstICurve, List<List<ICurve>> lstIHatchProfile,System.Windows.Size imageSize, double? dLengthLabel = null, double? dWidthLabel = null){var curvesTemp = new List<ICurve>();curvesTemp.AddRange(lstICurve);lstIHatchProfile?.ForEach(s => { curvesTemp.AddRange(s); });//  获取满布居中转换矩阵var matTrans = CurveUtils.GetScaleMatrix(curvesTemp, new Size(imageSize.Width, imageSize.Height - 12));//  转换到满布居中HMatrix3 mat = new HMatrix3();mat.M00 = matTrans.Value.M11;mat.M01 = matTrans.Value.M12;mat.M10 = matTrans.Value.M21;mat.M11 = matTrans.Value.M22;mat.M02 = matTrans.Value.OffsetX;mat.M12 = matTrans.Value.OffsetY;lstICurve = CurveUtils.CreateTransform(lstICurve, mat);for (int cntItem = 0; cntItem < lstIHatchProfile.Count; cntItem++){lstIHatchProfile[cntItem] = CurveUtils.CreateTransform(lstIHatchProfile[cntItem], mat);}//  创建虚拟画布DrawingVisual drawingVisual = new DrawingVisual();DrawingContext drawingContext = drawingVisual.RenderOpen();Rect rect = new Rect(new Point(0, 0), imageSize);drawingContext.DrawRectangle(Brushes.White, (Pen)null, rect);Pen pen = new Pen(Brushes.Black, 2);foreach (var icurve in lstICurve){DrawCurve(drawingContext, pen, icurve);}int cntPro = -1;foreach (var profile in lstIHatchProfile){DrawProfile(drawingContext, Brushes.LightBlue, pen, profile);var boundBox = CurveUtils.GetBoundBox(profile);var dir = boundBox.MaxPoint - boundBox.MinPoint;double fontSize = Math.Max(15.0, Math.Min(dir.X, dir.Y) * 0.2);DrawText(drawingContext, (++cntPro).ToString(), boundBox.Center, fontSize);}DrawLabel(drawingContext, dLengthLabel, dWidthLabel, imageSize);drawingContext.Close();//截虚拟画布并生成为本地图片文件RenderTargetBitmap bmp = new RenderTargetBitmap((int)imageSize.Width, (int)imageSize.Height, 96, 96, PixelFormats.Pbgra32);bmp.Render(drawingVisual);BitmapEncoder encoder = new JpegBitmapEncoder();encoder.Frames.Add(BitmapFrame.Create(bmp));using (MemoryStream stream = new MemoryStream()){encoder.Save(stream);return new System.Drawing.Bitmap(stream);}}