void OnCanvasViewPaintSurface(object sender, SkiaSharp.Views.Forms.SKPaintSurfaceEventArgs args)
        {
            SkiaSharp.SKImageInfo info    = args.Info;
            SkiaSharp.SKSurface   surface = args.Surface;
            SkiaSharp.SKCanvas    canvas  = surface.Canvas;
            canvas.Clear();
            SkiaSharp.SKRect bounds;
            SkiaSharp.SKPath path = SkiaSharp.SKPath.ParseSvgPathData((string)this.Resources["PathString"]);
            path.GetTightBounds(out bounds);
            SkiaSharp.SKPaint paint = new SkiaSharp.SKPaint
            {
                Style       = SkiaSharp.SKPaintStyle.Stroke,
                Color       = SkiaSharp.SKColors.Black,
                StrokeWidth = 10,
                StrokeCap   = SkiaSharp.SKStrokeCap.Round,
                StrokeJoin  = SkiaSharp.SKStrokeJoin.Round
            };
            canvas.Translate(info.Width / 2, info.Height / 2);

            canvas.Scale(info.Width / (bounds.Width + paint.StrokeWidth),
                         info.Height / (bounds.Height + paint.StrokeWidth));

            canvas.Translate(-bounds.MidX, -bounds.MidY);

            canvas.DrawPath(path, paint);
        }
Example #2
0
        /// <summary>
        /// 生成二维码(320*320)
        /// </summary>
        /// <param name="text">文本内容</param>
        /// <param name="format">保存格式</param>
        /// <param name="logoImgae">Logo图片(缩放到真实二维码区域尺寸的1/6)</param>
        /// <param name="keepWhiteBorderPixelVal">白边处理(负值表示不做处理,最大值不超过真实二维码区域的1/10)</param>
        /// <returns></returns>
        public static byte[] QRCoder(string text, SkiaSharp.SKEncodedImageFormat format, byte[] logoImgae = null, int keepWhiteBorderPixelVal = -1)
        {
            byte[] reval        = null;
            int    width        = 320;
            int    height       = 320;
            var    qRCodeWriter = new ZXing.QrCode.QRCodeWriter();
            var    hints        = new Dictionary <ZXing.EncodeHintType, object>();

            hints.Add(ZXing.EncodeHintType.CHARACTER_SET, "utf-8");
            hints.Add(ZXing.EncodeHintType.QR_VERSION, 8);
            hints.Add(ZXing.EncodeHintType.ERROR_CORRECTION, ZXing.QrCode.Internal.ErrorCorrectionLevel.Q);
            var bitMatrix = qRCodeWriter.encode(text, ZXing.BarcodeFormat.QR_CODE, width, height, hints);
            var w         = bitMatrix.Width;
            var h         = bitMatrix.Height;
            var sKBitmap  = new SkiaSharp.SKBitmap(w, h);

            int blackStartPointX = 0;
            int blackStartPointY = 0;
            int blackEndPointX   = w;
            int blackEndPointY   = h;

            #region --绘制二维码(同时获取真实的二维码区域起绘点和结束点的坐标)--
            var sKCanvas     = new SkiaSharp.SKCanvas(sKBitmap);
            var sKColorBlack = SkiaSharp.SKColor.Parse("000000");
            var sKColorWihte = SkiaSharp.SKColor.Parse("ffffff");
            sKCanvas.Clear(sKColorWihte);
            bool blackStartPointIsNotWriteDown = true;
            for (var y = 0; y < h; y++)
            {
                for (var x = 0; x < w; x++)
                {
                    var flag = bitMatrix[x, y];
                    if (flag)
                    {
                        if (blackStartPointIsNotWriteDown)
                        {
                            blackStartPointX = x;
                            blackStartPointY = y;
                            blackStartPointIsNotWriteDown = false;
                        }
                        blackEndPointX = x;
                        blackEndPointY = y;
                        sKCanvas.DrawPoint(x, y, sKColorBlack);
                    }
                    else
                    {
                        //sKCanvas.DrawPoint(x, y, sKColorWihte);//不用绘制(背景是白色的)
                    }
                }
            }
            sKCanvas.Dispose();
            #endregion

            int qrcodeRealWidth  = blackEndPointX - blackStartPointX;
            int qrcodeRealHeight = blackEndPointY - blackStartPointY;

            #region -- 处理白边 --
            if (keepWhiteBorderPixelVal > -1)//指定了边框宽度
            {
                var borderMaxWidth = (int)Math.Floor((double)qrcodeRealWidth / 10);
                if (keepWhiteBorderPixelVal > borderMaxWidth)
                {
                    keepWhiteBorderPixelVal = borderMaxWidth;
                }
                var nQrcodeRealWidth  = width - keepWhiteBorderPixelVal - keepWhiteBorderPixelVal;
                var nQrcodeRealHeight = height - keepWhiteBorderPixelVal - keepWhiteBorderPixelVal;

                var sKBitmap2 = new SkiaSharp.SKBitmap(width, height);
                var sKCanvas2 = new SkiaSharp.SKCanvas(sKBitmap2);
                sKCanvas2.Clear(sKColorWihte);
                //二维码绘制到临时画布上时无需抗锯齿等处理(避免文件增大)
                sKCanvas2.DrawBitmap(
                    sKBitmap,
                    new SkiaSharp.SKRect
                {
                    Location = new SkiaSharp.SKPoint {
                        X = blackStartPointX, Y = blackStartPointY
                    },
                    Size = new SkiaSharp.SKSize {
                        Height = qrcodeRealHeight, Width = qrcodeRealWidth
                    }
                },
                    new SkiaSharp.SKRect
                {
                    Location = new SkiaSharp.SKPoint {
                        X = keepWhiteBorderPixelVal, Y = keepWhiteBorderPixelVal
                    },
                    Size = new SkiaSharp.SKSize {
                        Width = nQrcodeRealWidth, Height = nQrcodeRealHeight
                    }
                });

                blackStartPointX = keepWhiteBorderPixelVal;
                blackStartPointY = keepWhiteBorderPixelVal;
                qrcodeRealWidth  = nQrcodeRealWidth;
                qrcodeRealHeight = nQrcodeRealHeight;

                sKCanvas2.Dispose();
                sKBitmap.Dispose();
                sKBitmap = sKBitmap2;
            }
            #endregion

            #region -- 绘制LOGO --
            if (logoImgae != null && logoImgae.Length > 0)
            {
                SkiaSharp.SKBitmap sKBitmapLogo = SkiaSharp.SKBitmap.Decode(logoImgae);
                if (!sKBitmapLogo.IsEmpty)
                {
                    var sKPaint2 = new SkiaSharp.SKPaint
                    {
                        FilterQuality = SkiaSharp.SKFilterQuality.None,
                        IsAntialias   = true
                    };
                    var logoTargetMaxWidth  = (int)Math.Floor((double)qrcodeRealWidth / 6);
                    var logoTargetMaxHeight = (int)Math.Floor((double)qrcodeRealHeight / 6);
                    var qrcodeCenterX       = (int)Math.Floor((double)qrcodeRealWidth / 2);
                    var qrcodeCenterY       = (int)Math.Floor((double)qrcodeRealHeight / 2);
                    var logoResultWidth     = sKBitmapLogo.Width;
                    var logoResultHeight    = sKBitmapLogo.Height;
                    if (logoResultWidth > logoTargetMaxWidth)
                    {
                        var r = (double)logoTargetMaxWidth / logoResultWidth;
                        logoResultWidth  = logoTargetMaxWidth;
                        logoResultHeight = (int)Math.Floor(logoResultHeight * r);
                    }
                    if (logoResultHeight > logoTargetMaxHeight)
                    {
                        var r = (double)logoTargetMaxHeight / logoResultHeight;
                        logoResultHeight = logoTargetMaxHeight;
                        logoResultWidth  = (int)Math.Floor(logoResultWidth * r);
                    }
                    var pointX = qrcodeCenterX - (int)Math.Floor((double)logoResultWidth / 2) + blackStartPointX;
                    var pointY = qrcodeCenterY - (int)Math.Floor((double)logoResultHeight / 2) + blackStartPointY;

                    var sKCanvas3 = new SkiaSharp.SKCanvas(sKBitmap);
                    var sKPaint   = new SkiaSharp.SKPaint
                    {
                        FilterQuality = SkiaSharp.SKFilterQuality.Medium,
                        IsAntialias   = true
                    };
                    sKCanvas3.DrawBitmap(
                        sKBitmapLogo,
                        new SkiaSharp.SKRect
                    {
                        Location = new SkiaSharp.SKPoint {
                            X = 0, Y = 0
                        },
                        Size = new SkiaSharp.SKSize {
                            Height = sKBitmapLogo.Height, Width = sKBitmapLogo.Width
                        }
                    },
                        new SkiaSharp.SKRect
                    {
                        Location = new SkiaSharp.SKPoint {
                            X = pointX, Y = pointY
                        },
                        Size = new SkiaSharp.SKSize {
                            Height = logoResultHeight, Width = logoResultWidth
                        }
                    }, sKPaint);
                    sKCanvas3.Dispose();
                    sKPaint.Dispose();
                    sKBitmapLogo.Dispose();
                }
                else
                {
                    sKBitmapLogo.Dispose();
                }
            }
            #endregion

            SkiaSharp.SKImage sKImage = SkiaSharp.SKImage.FromBitmap(sKBitmap);
            sKBitmap.Dispose();
            var data = sKImage.Encode(format, 75);
            sKImage.Dispose();
            reval = data.ToArray();
            data.Dispose();

            return(reval);
        }