Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.

HiRez

macrumors 603
Original poster
Jan 6, 2004
6,250
2,576
Western US
Hello, I am trying to figure out how to do real-time rendering using OpenGL and (preferably) Core Animation, and to have that output delivered not to a screen (ie. directly out of the GPU), but to an internal SDI video output card, such as AJA Kona or Blackmagic Decklink. I don't need help so much with OpenGL or Core Animation rendering, but I need to know how to get that rendered output onto the card, which would be fixed at 720x486 @ 29.97 fps (NTSC video). I think I have to use QuickTime to accomplish this, am I correct about that? I need to do animations in real-time using the GPU, which are constantly output from the card, so it can't be a fixed, pre-rendered QuickTime movie.

So can anyone walk me through a high-level overview of the steps I need to go through to assemble this pipeline? As best I can guess, I need to somehow grab the CA or OGL rendering buffer and send that through QuickTime to an Output Component? But what sort of QT Movie do I need to set up, or do I need to use a Movie object at all? How do I get access to the CA or OGL buffer needed and tell QuickTime about it? How and where do I do my rendering to accomplish this in real-time? Do I just render where I want, and QuickTime grabs whatever is in the buffer when it needs it? Or does QuickTime tell me when I need to render though a callback?

I know it's possible and I understand fragments, but I'm stumped on where to start. Any help would be appreciated!
 

Saladinos

macrumors 68000
Feb 26, 2008
1,845
4
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.