how can I capture a drawn/painted stroke?

This isn't directly about After Effects, but the end result is something I will use with After Effects...so here goes:

I'm looking for a way to use Photoshop or Corel Painter to "draw" an alphabet, while capturing the strokes as they are done in real time. I don't want to see the application's screen cursor. I also don't want to take the completed letter(s) and reveal them with a matte. This doesn't look real, and is also problematic where lines intersect. So, I'm thinking there must be a way to do a video screen capture, but I'm not familiar with applications that do this. Can anyone suggest how to go about this?

Here's an example of what I'd like to recreate:

http://videohive.net/item/mondo/3063469?sso?WT.ac=search_item&WT.seg_1 =search_item&WT.z_author=EmperorVFX

This example appears to have been done with real media, ink and brush. I'm guessing the artist may have shot video from behind a translucent substrate as the letters were drawn, and then flipped the video (so the letters weren't backwards). It looks great, but I'm hoping there is a way to mimic this effect on my Mac. Any suggestions would be appreciated.

thanks!