How to write display driver?

How to create a display for OS X?

• I need to write what I think is a display driver for OS X. It's like those "Use your iPad as a second monitor!" apps, but I need to write the OS X software that will register another display with OS X, and give me the pixel data so I can use it for my various needs. Where do I get started? I've read about IOKit, but I don't quite understand what I need to do to tell OS X that I'm a monitor, and then what the pixel data is going to look like. A few links to the classes/headers/etc that I'm going to have to read through would be fine as well, but if anyone has done this and knows the particulars it would be very helpful. Also, will this have to be a kernel extension, or is it possible to write a userspace IOKit driver that gives a second monitor to OS X? Lastly, to be clear, I just want the pixel data that would be sent to a second monitor (either mirrored or extended) - I'm not actually attaching a monitor on, or an I/O device.

• Answer:

  you could take a look at: http://code.google.com/p/ioproxyvideofamily/ maybe as a starting point.