I need help - I can help - DARenderPageToDC() slowing down form processing.

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DARenderPageToDC() slowing down form processing.

Printed From: Debenu Quick PDF Library - PDF SDK Community Forum
Category: For Users of the Library
Forum Name: I need help - I can help
Forum Description: Problems and solutions while programming with the Debenu Quick PDF Library and Debenu PDF Viewer SDK
URL: http://www.quickpdf.org/forum/forum_posts.asp?TID=1474
Printed Date: 29 Sep 24 at 1:12AM
Software Version: Web Wiz Forums 11.01 - http://www.webwizforums.com

Topic: DARenderPageToDC() slowing down form processing.

Posted By: Roulette
Subject: DARenderPageToDC() slowing down form processing.
Date Posted: 06 Jun 10 at 11:47PM

I am using QuickPDF's DARenderPageToDC() function in a background thread in a form-based application. I have tried setting the background thread to ThreadPriority.Lowest. Despite that, when QuickPDF is rendering (to an HDC that is never displayed) processing events on the form becomes very sluggish, often taking over a second to register things like button clicks or moving the form to a new location on the screen.

I am on an Intel i5 750 (2.67 GHz quad-core) and there are no other background threads running. If I disable the single DARenderPageToDC() line (and leave in the rest of what happens in the background thread such as opening the PDF, retrieving the number of pages, saving the image via a custom function, etc.) the form registers events as quickly as you would expect.

Any ideas as to how to use DARenderPageToDC() in a way that is more friendly in a multi-threaded application? I'm assuming that function must be multi-threaded? Can someone confirm that and, if so, what priority are its child threads?

- Roulette