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Occlusion Query speed troubles

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I would like to find out if this is a major problem or some implementation problem. I want to do some transparency rendering in my deferred rendering engine and for this I wanted to do a "sort of" depth peeling ( real depth peeling is a no-go due to some wrong-thinking by the original inventors ). Now this would require an occlusion query somewhere to figure out when to stop. I measured for an occlusion to take from 4ms up to 17ms. This is insane ( and totally useless for any real time application ). Now are those typical time values for an occlusion query or is something wrong at my end ( code wise or hardware driver wise )?

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I'm not sure about the exact timings, the recommandation seems to wait at least 2-3 frames for the results (depending on double or triple buffering). The card is supposed to buffer for the coming X frames but if you wait for results that goes out the window since the previous frames needs to be fully completed before you can start with the next one.

They are mostly used conservatively to determine things for an time interval. Like is the (swept) bounding box of this object visible? Ie will it become visible in 2-3 frames or can I keep not drawing it, etc...

On some consoles it can be much faster though (or so I've heard!)!

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