/// <summary>
/// Start/Continue progressive rendering for specified page
/// </summary>
/// <param name="page">Pdf page object</param>
/// <param name="pageRect">Actual page's rectangle. </param>
/// <param name="pageRotate">Page orientation: 0 (normal), 1 (rotated 90 degrees clockwise), 2 (rotated 180 degrees), 3 (rotated 90 degrees counter-clockwise).</param>
/// <param name="renderFlags">0 for normal display, or combination of flags defined above.</param>
/// <param name="useProgressiveRender">True for use progressive render</param>
/// <returns>Null if page still painting, PdfBitmap object if page successfully rendered.</returns>
internal bool RenderPage(PdfPage page, Rectangle pageRect, PageRotate pageRotate, RenderFlags renderFlags, bool useProgressiveRender)
{
if (!this.ContainsKey(page))
{
ProcessNew(page); //Add new page into collection
if (PaintBackground != null)
{
PaintBackground(this, new EventArgs <Rectangle>(pageRect));
}
}
if ((renderFlags & (RenderFlags.FPDF_THUMBNAIL | RenderFlags.FPDF_HQTHUMBNAIL)) != 0)
{
this[page].status = ProgressiveRenderingStatuses.RenderDone + 4;
}
else if (!useProgressiveRender)
{
this[page].status = ProgressiveRenderingStatuses.RenderDone + 3;
}
PdfBitmap bitmap = this[page].Bitmap;
bool ret = ProcessExisting(bitmap ?? CanvasBitmap, page, pageRect, pageRotate, renderFlags);
if (bitmap != null)
{
Pdfium.FPDFBitmap_CompositeBitmap(CanvasBitmap.Handle, pageRect.X, pageRect.Y, pageRect.Width, pageRect.Height, bitmap.Handle, pageRect.X, pageRect.Y, BlendTypes.FXDIB_BLEND_NORMAL);
}
return(ret);
}