Retrieve a Disparity Map

I want to get the disparity map of the captured image.
It seems to work:
returned_state = zedCamera.retrieveMeasure(DisparityMap, MEASURE::DISPARITY, MEM::CPU);
The DisparityMap is a sl::Mat.

But now I have some questions:

  1. Is it computed in hardware in the camera ?
  2. What is contained in the different subpixels ?
    It’s a coloured image. But theoretically the disparity is only an integer value for each pixel desribing the disparity.
  3. Is it computed from left to right ?

Does anybody have any ideas?