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Frustum culling

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So, I have a lovely frustum culling algorithm. It works great, and tells me if the objects intersect or are wholly within my viewing frustum, but I'm not completely satisfied. It seems to me that once I've determined that all of an objects verticies are completely contained withing my view frustum there is no need for the graphics card to go through doing this itself, however I can't work out how to tell it not to. It seems to me this would give my vertex heavy rendering a bit of a hand, as it wouldn't have to do all that maths to ensure those verticies are within my clipping planes. Can it be done?

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I think the poster means if there is a way to disable the graphic card's internal "frustum culling"-check since the object is already determined to be fully visible.

I on the other hand don't know how or if it's possible. But I figure if you mess too much with it you might ending up with worse performance than you had before. :)

/Robert

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Quote:
Original post by Rasmadrak
I think the poster means if there is a way to disable the graphic card's internal "frustum culling"-check since the object is already determined to be fully visible.
I don't think there is, and there's no need because the operation is basically free in all decently-engineered pipelines.

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Quote:
Original post by Krohm
I don't think there is, and there's no need because the operation is basically free in all decently-engineered pipelines.


So theres no point in doing any frustrum culling yourself then?

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Quote:
Original post by bovinedragon
Quote:
Original post by Krohm
I don't think there is, and there's no need because the operation is basically free in all decently-engineered pipelines.


So theres no point in doing any frustrum culling yourself then?


Frustum culling is a much simpler operation than transforming and checking all the verticies of an object - you can just do one sphere test and skip all that hassle. It allows you to get rid of stuff before the graphics card even sees it.

I can understand how the internal stuff would be basically free - even if you were to skip it you'd still have to do all the expensive matrix transformations, right?

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