Optimizing Interop Plotting to PDF - C#

[grindstaffp]

Like many here before, I am needing to essentially batch plot a set of drawings to PDF. I originally thought I would be using ObjectARX to do this but then found that ObjectARX projects are typically addins for AutoCAD. My second thought was to take advantage of accoreconsole but I am not sure my use case fits necessarily works since accoreconsole expects a script to do anything. This would probably be my preferred method of saving my drawings to PDF so if there is a way to use accoreconsole I am open to suggestion.

So far I have functional code that sends a set of drawings to AutoCAD through COM and gives me PDF files. I have a few problems however:

1. I cannot figure out how to prevent the resulting PDF from being opened.
2. Once all of the drawings are processed and I quit AutoCAD, the first file processed asks if I want to save changes. What type of object to I need for "object SaveChanges" when calling Close() on a document?
3. The process is relatively slow. To process 32 files takes around 2 minutes. I am using a single instance of AutoCAD so the slowdown shouldn't be occurring there. Obviously using Interop is never going to be the quickest but maybe there's a way to speed this up?

Code for reference:

static void Main(string[] args)
        {
            Type acType = Type.GetTypeFromProgID("AutoCAD.Application.23");
            AutoCAD.AcadApplication acApp = null; //new AutoCAD.AcadApplication();

            try
            {
                acApp = (AutoCAD.AcadApplication)Marshal.GetActiveObject("AutoCAD.Application");
            }
            catch
            {
                acApp = new AutoCAD.AcadApplication();
                //AutoCAD.AcadApplication acApp = (AutoCAD.AcadApplication)Activator.CreateInstance(acType, true);
            }

            acApp.Visible = false;

            AutoCAD.AcadDocument acDoc = null;

            string dwgDir = @"H:\Development\C#\Misc\44OP-257468\44OP-257468\MDT\";
            var dwgs = Directory.EnumerateFiles(dwgDir, "*.dwg");
            foreach (var dwg in dwgs)
            {
                FileInfo dwgInfo = new FileInfo(dwg);
                string outputFile = String.Format("G:\\temp\\{0}.pdf", dwgInfo.Name);
                acDoc = acApp.Documents.Open(dwg);
                    
                while (!acApp.GetAcadState().IsQuiescent)
                {
                    System.Threading.Thread.Sleep(25);
                }

                acDoc.ActiveSpace = AutoCAD.Common.AcActiveSpace.acModelSpace;

                var acPlotCfg = acDoc.PlotConfigurations;
                acPlotCfg.Add("PDF", true); // If second parameter is not true, exception is caused by acDoc.ActiveLayout.CopyFrom(PlotConfig);
                AutoCAD.Common.AcadPlotConfiguration PlotConfig = acPlotCfg.Item("PDF");
                PlotConfig.ConfigName = "DWG To PDF.pc3";
                PlotConfig.CanonicalMediaName = "ANSI_expand_A_(8.50_x_11.00_Inches)";
                PlotConfig.PlotHidden = true;
                PlotConfig.StandardScale = AutoCAD.Common.AcPlotScale.acScaleToFit;
                PlotConfig.PlotType = AutoCAD.Common.AcPlotType.acExtents;
                PlotConfig.PaperUnits = AutoCAD.Common.AcPlotPaperUnits.acInches;
                PlotConfig.PlotRotation = AutoCAD.Common.AcPlotRotation.ac90degrees;
                PlotConfig.CenterPlot = false;
                PlotConfig.PlotWithLineweights = true;
                PlotConfig.PlotWithPlotStyles = true;
                //PlotConfig.StyleSheet = "acad.ctb";
                PlotConfig.RefreshPlotDeviceInfo();

                acDoc.ActiveLayout.CopyFrom(PlotConfig);    // Need to have this or resulting PDF does not seem to apply the PlotConfig.
                acDoc.SetVariable("BACKGROUNDPLOT", 0);
                acDoc.Plot.QuietErrorMode = true;
                acDoc.Plot.PlotToFile(outputFile, PlotConfig.ConfigName);

                acDoc.Close(false, null);

                Console.WriteLine(String.Format("PDF Created For: {0}", dwgInfo.Name));
            }
            acApp.Quit();

            Console.WriteLine("Done");
            Console.ReadLine();
        }

One thought I had that may or may not have any performance benefit at all would be to create an ObjectARX add-in that builds on the concepts of this example code. My thought is that perhaps I could send the add-in a list of drawings, output folder and filenames, and page orientation information and handle the plot that way.

Another thought would be to automate accoreconsole as I mentioned above. This *may* be the best option as I could spawn a bunch of instances and process files concurrently.

Any direction of which way to go is much appreciated.

[_gile]

Did you try using the Core Console?

[grindstaffp]

I have used the core console and manually created a pdf running through the PLOT command but I am unsure of how to automate the use of core console without providing it a script to run. If I want to provide different output directories based on a given project I don't know a way to do that.

Any pointers?

[_gile]

If the use of .bat file(s) (as in the Kean example) does not suit you, you can call AutoLISP expressions from the script file or, if you prefer, create a custom .NET command (with only references to accoremgd.dll and acbdmgd.dll), NETLOAD it and run it from the script.