/// <summary>
/// Process existing pages
/// </summary>
/// <returns>Null if page still painting, PdfBitmap object if page successfully rendered.</returns>
private bool ProcessExisting(PdfPage page, Rectangle pageRect, PageRotate pageRotate, RenderFlags renderFlags)
{
switch (this[page].status)
{
case ProgressiveRenderingStatuses.RenderReader:
this[page].status = page.StartProgressiveRender(CanvasBitmap, pageRect.X, pageRect.Y, pageRect.Width, pageRect.Height, pageRotate, renderFlags, null);
if (this[page].status == ProgressiveRenderingStatuses.RenderDone)
{
return(true);
}
return(false); //Start rendering. Return nothing.
case ProgressiveRenderingStatuses.RenderDone:
page.CancelProgressiveRender();
this[page].status = ProgressiveRenderingStatuses.RenderDone + 2;
return(true); //Stop rendering. Return image.
case ProgressiveRenderingStatuses.RenderDone + 2:
return(true); //Rendering already stoped. return image
case ProgressiveRenderingStatuses.RenderDone + 3:
this[page].status = ProgressiveRenderingStatuses.RenderDone + 2;
page.RenderEx(CanvasBitmap, pageRect.X, pageRect.Y, pageRect.Width, pageRect.Height, pageRotate, renderFlags);
return(true); //Rendering in non progressive mode
case ProgressiveRenderingStatuses.RenderDone + 4:
this[page].status = ProgressiveRenderingStatuses.RenderDone + 2;
DrawThumbnail(page, pageRect, pageRotate, renderFlags);
return(true); //Rendering thumbnails
case ProgressiveRenderingStatuses.RenderTobeContinued:
this[page].status = page.ContinueProgressiveRender();
return(false); //Continue rendering. Return nothing.
case ProgressiveRenderingStatuses.RenderFailed:
default:
CanvasBitmap.FillRect(pageRect.X, pageRect.Y, pageRect.Width, pageRect.Height, Color.Red);
CanvasBitmap.FillRect(pageRect.X + 5, pageRect.Y + 5, pageRect.Width - 10, pageRect.Height - 10, Color.White);
page.CancelProgressiveRender();
this[page].status = ProgressiveRenderingStatuses.RenderDone + 2;
return(true); //Error occur. Stop rendering. return image with error
}
}