I'm writing a user's manual for a Perl/Tk program (Win32). My usual approach to illustrating such a manual would be to do screen captures of the program in action, then cut out individual controls or groups of controls in Corel PhotoPaint to paste into the text near their explanations. But this hand-cutting gets very tedious, to say the least.

I was thinking that, since Tk provides all the tools needed to determine each widget's extents on the screen, it would be an easy matter to include a subroutine to selectively capture individual widgets or groups of widgets and write them out as, say, BMP files, thus eliminating all the hand cutting. It would be easy, that is, if there was a way to read arbitrary pixels from the screen. And that's where I'm stuck. Tk doesn't seem to provide such a facility (unless I'm overlooking something really obvious). I'd prefer not going through the Windows API if there's a Perl module with this capability built-in. But a search of CPAN didn't turn up anything promising.

An alternative, of course, would be to reparent the desired controls, in turn, in a separate top-level window, capturing each with Corel Capture. But packed widgets are so plastic, they might not look the same removed thus from their normal context.

Any ideas?

In reply to Reading screen pixels by Dr. Mu

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