COW Tutorials: After Effects Open GL Demystified

[Andrew Kramer]

Nice tutorial. Well explained and you covered tons of points.

Andrew

[John Dickinson]

Yes, nice job Mylenium, clear and concise.

JD

John Dickinson
Motionworks
http://www.motionworks.com.au

[John Dickinson]

Yes, nice job Mylenium, clear and concise.

JD

John Dickinson
Motionworks
http://www.motionworks.com.au

[Mylenium]

Thanks for all your compliments. One question: Is my voice halfway bearable from the point of a native English-speaking person?

Mylenium

[Pour Myl

[Uwe Lansing]

Hi Mylenium,

some greetings from Hamburg to Leipzig. You made a good job, but when you address the topic “OpenGL Renderer” at the end, the Tutorial breaks off suddenly. Particularly this topic would have interested me => speed + quality of OpengL Renderer. Unfortunately the results with my own benchmarks were not good (ATI Randeon 9600XT)… longer than the rendering without “OpenGL Renderer” and no advantage with the quality, rather the opposite………….

regards
Uwe

[Uwe Lansing]

Hi Mylenium,

some greetings from Hamburg to Leipzig. You made a good job, but when you address the topic “OpenGL Renderer” at the end, the Tutorial breaks off suddenly. Particularly this topic would have interested me => speed + quality of OpengL Renderer. Unfortunately the results with my own benchmarks were not good (ATI Randeon 9600XT)… longer than the rendering without “OpenGL Renderer” and no advantage with the quality, rather the opposite………….

regards
Uwe

[John Dickinson]

Considering English is not your first language, it was excellent.

JD

John Dickinson
Motionworks
http://www.motionworks.com.au

[Mylenium]

Quite honestly I haven’t tested that yet, so I left it out. Coming from the 3D world I know the limitations of OpenGL and even pixel shaders (what OpenGL 2.0 is all about) don’t change that. In general I don’t consider any OpenGL rendered stuff as “production ready”, not in 3D nor in 2D. Anyway, I doubt that your hardware is to blame for the slowness.

OpenGL can only optimize comparably few things, so if you are using lots of nesting and non-accelerated effects, you loose the speed advantage, or moreover give yourself a hard time because there is always at least an extra step involved in translating the software render buffer and OpenGL buffer back and forth. This would explain accelerated renders being slower than software-only stuff. The same can happen when using multiple accelerated effects – if your graphics card cannot hold all buffers, they will be temporarily cached as software buffers before the next processing step , adding additional overhead. You should only use OpenGL for straightforward things like interactive color correction where OpenGL can literally “burst” free its power.

Mylenium

[Pour Myl

[Lessevolvedman]

Mylenium…your voice reminds me so much of my multimedia coordinator at school… werner.
Very simple, clear and precise…. absolutely no problems taking in your extremely helpful points.

Cheers

[Uwe Lansing]

Thank you Mylenium for your detailed answer…

regards
Uwe