I figured it out, Richard. You have to do a FillRect(...) on the pristine CRect rcl = pInfo->m_rectDraw (in OnPrint()). That should happen before the printer thread is started. Thanks.

I use FillRect(...) for the screen but I can't get it to work for a printer. App is pretty much ordinary MFC with Doc/View arch. A little unusual is that I use worker threads for printing and painting. The threads use GDI resources instead of CDC. Did I hear you ask why? I use an image printer to print straight to jpg files. I want a dark background in some of the jpgs. Then I use Windows Movie Maker to add the jpgs and a soundtrack. Walla, out pops an MP4. Loads of fun.

I program as a hobby (using VS12) and I have an entertaining program I would like to share. Trouble is I am not a "verified programmer". How do I become one? I would also like to share the source code. It has all kinds of goodies I'd love to discuss. To get an idea of what it does, go to my web site "http://www.mirrorgrindingmachine.com/Rainbow/ and click on the *.jpg file.