I need a piece of code that makes screenshot of window of third party application independently of its state: active, visible, hidden or MINIMIZED. It can be written in C++ or Delphi but I need resulting bitmap in Delphi application. It must be fast and efficient since application I'm writing will use it frequently.
I need that code to take snapshot at up to 5 shot/sec rate, so, "maximize-take_snap-minimize" approach is unacceptable.
I'd prefer a solution described in article http://www.fengyuan.com/article/wmprint.html or similar.
Memory should be used to pass bitmap from C++ code to Delphi (but not clipboard).