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ade-the-heat

VBOs what are they good for ..?!

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Now, we had compiled vertex arrays as an extension that made everything go faster. Q1:So what do VBOs do that compiled VAs don''t do ? Yes I read the info on VBOs and it said stuff about cache memory (which is what I thought compiled VAs used anyhow). Also, if they are just faster than comp.VAs then why not just make comp.VAs faster and no have VBOs? Q2: Apart from drawing terrains really quickly does anyone have simple to understand examples that use VBOs in other genuinely usable ways ? cheers Ade

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quote:
Original post by ade-the-heat
Q1:So what do VBOs do that compiled VAs don''t do ? Yes I read the info on VBOs and it said stuff about cache memory (which is what I thought compiled VAs used anyhow).
Also, if they are just faster than comp.VAs then why not just make comp.VAs faster and no have VBOs?

Q2: Apart from drawing terrains really quickly does anyone have simple to understand examples that use VBOs in other genuinely usable ways ?



Q1: Speed. VBOs allow you to choose the memory location where the geometry (and index memory) is stored. There can be no better place to put static geometry than the card itself. CVAs don''t do that. In fact CVAs only work nicely in multipass effects.
The mechanism for VBOs is very diferent from CVAs. Just use VBOs for everything, even display lists

Q2: Every way you use a VBOs is a good way. Remenber that you can store index memory in VBOs to. And it takes care of syncronization issues all well.

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