Neuerstellung

- Quelle: https://github.com/oxyplot/oxyplot

Source/OxyPlot.SkiaSharp/PdfExporter.cs

@@ -0,0 +1,71 @@
+// --------------------------------------------------------------------------------------------------------------------
+// <copyright file="PdfExporter.cs" company="OxyPlot">
+//   Copyright (c) 2020 OxyPlot contributors
+// </copyright>
+// --------------------------------------------------------------------------------------------------------------------
+
+namespace OxyPlot.SkiaSharp
+{
+    using global::SkiaSharp;
+    using System.IO;
+
+    /// <summary>
+    /// Provides functionality to export plots to pdf using the SkiaSharp renderer.
+    /// </summary>
+    public class PdfExporter : IExporter
+    {
+        /// <summary>
+        /// Gets or sets the export height (in points, where 1 point equals 1/72 inch).
+        /// </summary>
+        public float Height { get; set; }
+
+        /// <summary>
+        /// Gets or sets the export width (in points, where 1 point equals 1/72 inch).
+        /// </summary>
+        public float Width { get; set; }
+
+        /// <summary>
+        /// Gets or sets a value indicating whether text shaping should be used when rendering text.
+        /// </summary>
+        public bool UseTextShaping { get; set; } = true;
+
+        /// <summary>
+        /// Exports the specified model to a file.
+        /// </summary>
+        /// <param name="model">The model.</param>
+        /// <param name="path">The path.</param>
+        /// <param name="width">The width (points).</param>
+        /// <param name="height">The height (points).</param>
+        public static void Export(IPlotModel model, string path, float width, float height)
+        {
+            using var stream = File.OpenWrite(path);
+            Export(model, stream, width, height);
+        }
+
+        /// <summary>
+        /// Exports the specified model to a stream.
+        /// </summary>
+        /// <param name="model">The model.</param>
+        /// <param name="stream">The output stream.</param>
+        /// <param name="width">The width (points).</param>
+        /// <param name="height">The height (points).</param>
+        public static void Export(IPlotModel model, Stream stream, float width, float height)
+        {
+            var exporter = new PdfExporter { Width = width, Height = height };
+            exporter.Export(model, stream);
+        }
+
+        /// <inheritdoc/>
+        public void Export(IPlotModel model, Stream stream)
+        {
+            using var document = SKDocument.CreatePdf(stream);
+            using var pdfCanvas = document.BeginPage(this.Width, this.Height);
+            using var context = new SkiaRenderContext { RenderTarget = RenderTarget.VectorGraphic, SkCanvas = pdfCanvas, UseTextShaping = this.UseTextShaping };
+            const float dpiScale = 72f / 96;
+            context.DpiScale = dpiScale;
+            model.Update(true);
+            pdfCanvas.Clear(model.Background.ToSKColor());
+            model.Render(context, new OxyRect(0, 0, this.Width / dpiScale, this.Height / dpiScale));
+        }
+    }
+}