Cairo.Context.SetSourceRGB C# (CSharp) Метод

        public void SetSourceRGB(double r, double g, double b)
        {
            CheckDisposed ();
            NativeMethods.cairo_set_source_rgb (handle, r, g, b);
        }

        private void OnDrawPage(object obj, Gtk.DrawPageArgs args)
        {
            PrintContext context = args.Context;

            Cairo.Context cr    = context.CairoContext;
            double        width = context.Width;

            cr.Rectangle(0, 0, width, headerHeight);
            cr.SetSourceRGB(0.8, 0.8, 0.8);
            cr.FillPreserve();

            cr.SetSourceRGB(0, 0, 0);
            cr.LineWidth = 1;
            cr.Stroke();

            Pango.Layout layout = context.CreatePangoLayout();

            Pango.FontDescription desc = Pango.FontDescription.FromString("sans 14");
            layout.FontDescription = desc;

            layout.SetText(fileName);
            layout.Width     = (int)width;
            layout.Alignment = Pango.Alignment.Center;

            int layoutWidth, layoutHeight;

            layout.GetSize(out layoutWidth, out layoutHeight);
            double textHeight = (double)layoutHeight / (double)pangoScale;

            cr.MoveTo(width / 2, (headerHeight - textHeight) / 2);
            Pango.CairoHelper.ShowLayout(cr, layout);

            string pageStr = String.Format("{0}/{1}", args.PageNr + 1, numPages);

            layout.SetText(pageStr);
            layout.Alignment = Pango.Alignment.Right;

            cr.MoveTo(width - 2, (headerHeight - textHeight) / 2);
            Pango.CairoHelper.ShowLayout(cr, layout);

            layout = null;
            layout = context.CreatePangoLayout();

            desc      = Pango.FontDescription.FromString("mono");
            desc.Size = (int)(fontSize * pangoScale);
            layout.FontDescription = desc;

            cr.MoveTo(0, headerHeight + headerGap);
            int line = args.PageNr * linesPerPage;

            for (int i = 0; i < linesPerPage && line < numLines; i++)
            {
                layout.SetText(lines[line]);
                Pango.CairoHelper.ShowLayout(cr, layout);
                cr.RelMoveTo(0, fontSize);
                line++;
            }
            (cr as IDisposable).Dispose();
            layout = null;
        }