Question

How to render to an "offscreen" CWnd

Asked by: pcommons

If I have a CWnd object that is either not visible or that is clipped on the screen by another window, if I try to get access to the CWnd's DC for the purpose of copying the CWnd's image data to a bitmap using StretchBlt(), the areas of the CWnd that are not actually drawn and visible on the screen appear in the result as either the other window or black.

Is there a way to, well, create an "offscreen window" - a full blown CWnd that has its own bitmap/screen data - such that if I draw stuff to it and then try to StretchBlt() from it, the data is intact, even if part or all of the window is not visible on the screen?

Any help would be greatly appreciated.

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Asked On
2003-10-28 at 13:47:56ID20780945
Tags

offscreen

,

create

Topic

Windows MFC Programming

Participating Experts
3
Points
350
Comments
8

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Answers

 

Accepted Solution

by: DanRollinsPosted on 2003-10-28 at 17:40:08ID: 9638463

Rank: Genius

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Assisted Solution

by: AlexFMPosted on 2003-10-28 at 21:14:35ID: 9639483

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Expert Comment

by: pcommonsPosted on 2003-10-29 at 09:04:08ID: 9643495

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Expert Comment

by: DanRollinsPosted on 2003-10-29 at 11:39:42ID: 9644834

Rank: Genius

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Expert Comment

by: pcommonsPosted on 2003-10-29 at 13:22:31ID: 9645622

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Assisted Solution

by: vijay_visanaPosted on 2003-11-03 at 04:41:10ID: 9670363

Rank: Master

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Expert Comment

by: pcommonsPosted on 2004-08-20 at 09:19:12ID: 11852823

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