How can you know if a control is visible or invisible using Microsoft Active Accessibility

Question

I noticed that AccExplorer (accessibility explorer) shows when controls are visible or invisible. How does it determine this? The api for MSAA does not have a IsVisible function. Any ideas?

Edit: IsWindowVisible does not actually tell you if it has been drawn or not. Even if something is 100% obscuring the window, IsWindowVisible can still return TRUE.

Answer 1

You can test if a window (including controls) is visible with the standard IsWindowVisible() function.

Answer 2

This answer suggests using GetWindowPlacement().