How can I reduce the page flicker caused by PDFViewCtrl.update?

[Aaron]

Q:

I'm using the Java PDFViewCtrl.update() to refresh content after page updates.  However, this causes the entire canvas to blank white during, for example, an annotation refresh.  Is there any way to reduce this effect?

A:

You should be able to use variations of update() which only refresh a small area.  In particular, you can refresh only the area covered by an annotation:

https://www.pdftron.com/pdfnet/docs/PDFNetJava/pdftron/PDF/PDFViewCtrl.html#update(pdftron.PDF.Annot, int)

Additional update variants are documented at:

https://www.pdftron.com/pdfnet/docs/PDFNetJava/pdftron/PDF/PDFViewCtrl.html#update(java.awt.Graphics)

https://www.pdftron.com/pdfnet/docs/PDFNetJava/pdftron/PDF/PDFViewCtrl.html#update(pdftron.PDF.Rect)

The following article has further advice:

https://groups.google.com/d/msg/pdfnet-sdk/07ScwrJoJ4E/nbQXKOTRuK8J