Working with Watermark

Add Watermark in a DWG

Sometimes you want to add some watermarks to drawings to indicate what purpose of the drawings or who created them. Aspose.CAD for .NET allows you to add a watermark in a DWG file. This can be done through creating a Text or MText entity with a specific text height, rotation, style, adjustments and such should be adjusted as well to give a good look. For this, the API provides CadMText and CadText classes.

Sample Code

The code below shows how to achieve the same goal using Aspose.CAD for .NET

            // The path to the documents directory.
            string MyDir = RunExamples.GetDataDir_DWGDrawings();
            

           using(CadImage cadImage = (CadImage)Image.Load(MyDir + "Drawing11.dwg")) {

                //add new MTEXT
                CadMText watermark = new CadMText();
                watermark.Text = "Watermark message";
                watermark.InitialTextHeight = 40;
                watermark.InsertionPoint = new Cad3DPoint(300, 40);
                watermark.LayerName = "0";
                cadImage.BlockEntities["*Model_Space"].AddEntity(watermark);

                // or add more simple entity like Text
                CadText text = new CadText();
                text.DefaultValue = "Watermark text";
                text.TextHeight = 40;
                text.FirstAlignment = new Cad3DPoint(300, 40);
                text.LayerName = "0";
                cadImage.BlockEntities["*Model_Space"].AddEntity(text);

                // export to pdf
                CadRasterizationOptions rasterizationOptions = new CadRasterizationOptions();
                rasterizationOptions.PageWidth = 1600;
                rasterizationOptions.PageHeight = 1600;
                rasterizationOptions.Layouts = new[] { "Model" };
                PdfOptions pdfOptions = new PdfOptions();
                pdfOptions.VectorRasterizationOptions = rasterizationOptions;
                cadImage.Save(MyDir + "AddWatermark_out.pdf", pdfOptions);

            }