I'm on .net framework 4.8 in my WPF app and I have two usages on RDLC. 1st is a fully fetched ReportViewer that uses a DataTable from postgres, 2nd is just a LocalReport with small number of parameters rendered as EMF and printed directly with use of default printer.

They both have what would seem to be rendering issues, but just on monitors that have recommended scaling (RS) >100%. The outcome is squashing of letters vertically and adding some extra space in between (I can provide samples as soon as I get access to client machine again). If I just increase scaling on my 100% RS monitor, everything prints out just fine. If I replace the >100% RS monitor with a 1080p 100% RS one, again, everything prints out fine. Printouts on machines with monitors with >100% RS come out always messed up irrelevant of the scaling I set in Windows. Issues can be quickly reproduced with just 'Print Layout' view in ReportViewer, exporting to PDF produces same results.

Since I have ReportViewer and a direct printout of LocalReport I was able to try out several different approaches:

• Making the app DPIAware / not aware / true/PM etc. (also included manifest, App.config and App.xaml changes)
• Putting the ReportViewer in ViewBox
• Using DpiX/Y and PrintDpiX/Y on DeviceInfo
• ScaleTransform and DrawImageUnscaled on PrintPage callback with and without the DeviceInfo changes
• countless printer options in Windows

Client machines run on either latest Windows 10 or close to latest and are rather empty otherwise.

Does it ring any bells? Any idea for potential fix?

I would love to use RDLC in my app, for the simplicity of development and usage, but those issues are really a no go for the technology.

Code

No preview printout

Used to print a single document directly without preview from parameters.

    class CytologiaPrinter : IDisposable
    {
        private static readonly ILog log = LogManager.GetLogger(typeof(CytologiaPrinter));
        private int m_currentPageIndex;
        private IList<Stream> m_streams;

        private int WizytaID;
        private CytologiaAnkieta Cytologia;

        public CytologiaPrinter(int wizytaID)
        {
            WizytaID = wizytaID;
        }

        public CytologiaPrinter(CytologiaAnkieta cytologia)
        {
            Cytologia = cytologia;
        }

        public void Print()
        {
            try
            {
                CytologiaAnkieta cytologia;
                if (Cytologia == null)
                {
                    cytologia = DBCommunication.fetchCytologia(WizytaID);
                }
                else
                {
                    cytologia = Cytologia;
                }
                if (cytologia != null && cytologia.AnkietaNumer != null && cytologia.AnkietaNumer.Length > 0)
                {
                    LocalReport report = new LocalReport();
                    var cytologie = new List<CytologiaAnkieta>();
                    cytologie.Add(cytologia);
                    ReportDataSource reportDataSource = new ReportDataSource("DataSet1", cytologie);
                    report.DataSources.Add(reportDataSource);
                    report.ReportEmbeddedResource = "Suplement.CytologiaAnkieta.rdlc";

                    var parameters = new List<ReportParameter>();
                    //parameters.Add(...); //setting all parameters omitted for demo
                    report.SetParameters(parameters);
                    m_currentPageIndex = 0;
                    Print(cytologia);
                }
            }
            catch (Exception ex)
            {
                log.Error("Error (" + ex.Message + "), stack:" + ex.StackTrace);
            }
        }

        private Stream CreateStream(string name, string fileNameExtension, Encoding encoding, string mimeType, bool willSeek)
        {
            Stream stream = new MemoryStream();
            m_streams.Add(stream);
            return stream;
        }

        private void Export(LocalReport report)
        {
            string deviceInfo =
              @"<DeviceInfo>
                <OutputFormat>EMF</OutputFormat>
                <PageWidth>29.7cm</PageWidth>
                <PageHeight>21cm</PageHeight>
                <MarginTop>1cm</MarginTop>
                <MarginLeft>1cm</MarginLeft>
                <MarginRight>1cm</MarginRight>
                <MarginBottom>1cm</MarginBottom>
            </DeviceInfo>"; //printing in landscape
            Warning[] warnings;
            m_streams = new List<Stream>();
            report.Render("Image", deviceInfo, CreateStream,
               out warnings);
            if (warnings != null && warnings.Length > 0)
            {
                foreach (var warn in warnings)
                {
                    log.Warn("Cytologia printing issues: " + warn.Message);
                }
            }
            foreach (Stream stream in m_streams)
                stream.Position = 0;
        }

        private void PrintPage(object sender, PrintPageEventArgs ev)
        {
            Metafile pageImage = new
               Metafile(m_streams[m_currentPageIndex]);
            
            Rectangle adjustedRect = new Rectangle(
                ev.PageBounds.Left - (int)ev.PageSettings.HardMarginX,
                ev.PageBounds.Top - (int)ev.PageSettings.HardMarginY,
                ev.PageBounds.Width,
                ev.PageBounds.Height);

            ev.Graphics.FillRectangle(Brushes.White, adjustedRect);

            ev.Graphics.DrawImage(pageImage, adjustedRect);

            m_currentPageIndex++;
            ev.HasMorePages = m_currentPageIndex < m_streams.Count;
        }

        private void Print(CytologiaAnkieta cytologia)
        {
            if (m_streams == null || m_streams.Count == 0)
                throw new Exception("Error: no stream to print.");
            PrintDocument printDoc = new PrintDocument();
            printDoc.DefaultPageSettings.Landscape = true;

            if (!printDoc.PrinterSettings.IsValid)
            {
                throw new Exception("Error: cannot find the default printer.");
            }
            else
            {
                printDoc.PrintPage += new PrintPageEventHandler(PrintPage);
                m_currentPageIndex = 0;
                printDoc.Print();
            }
        }

        public void Dispose()
        {
            if (m_streams != null)
            {
                foreach (Stream stream in m_streams)
                    stream.Close();
                m_streams = null;
            }
        }
    }

Preview WinForms

Xaml

xmlns:rv="clr-namespace:Microsoft.Reporting.WinForms;assembly=Microsoft.ReportViewer.WinForms"
...
<WindowsFormsHost DockPanel.Dock="Bottom" Margin="0 0 0 0" >
    <rv:ReportViewer x:Name="RVDemo"/>
</WindowsFormsHost>

C# code part

        private void RaportGenerate_Click(object sender, RoutedEventArgs e)
        {
            RVDemo.Reset();
            ReportDataSource reportDataSource = new ReportDataSource("Ankiety", DBCommunication.fetchCytologiaAnkietyReport(...));
            RVDemo.LocalReport.DataSources.Add(reportDataSource);
            RVDemo.LocalReport.ReportEmbeddedResource = "Suplement.Cytologie.rdlc";
            var parameters = new List<ReportParameter>();
            //parameters.Add(...); // omitted for demo
            RVDemo.LocalReport.SetParameters(parameters);

            RVDemo.RefreshReport();
        }