triangle list vs. triangle strips

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Marc
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triangle list vs. triangle strips

Post by Marc » Wed Mar 30, 2005 11:45 am

Hi !

Is it better to have one submesh with one triangle list or is it better to use multiple submeshes with trianlge strips?

AFAIK having multiple submeshes restarts GPU unneccessarily often, while using triangle lists has an higher impact on memory usage. Is that everything?

Having one submesh represented as a triangle strip and also represented as a triangle list, is the 2nd one just larger or also a bit slower? Or is it really just more memory that is needed and if there is enough, there is no difference in speed?

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Re: triangle list vs. triangle strips

Post by haffax » Wed Mar 30, 2005 11:56 am

Marc wrote:Having one submesh represented as a triangle strip and also represented as a triangle list, is the 2nd one just larger or also a bit slower? Or is it really just more memory that is needed and if there is enough, there is no difference in speed?
There really shouldn't be a noticable speed difference between the two, so the overhead provoked by having multiple render operations for the submeshes is clearly greater than a possible benefit.
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Post by :wumpus: » Wed Mar 30, 2005 12:01 pm

You should really aim for minimizing the number of renderops. The gain from triangle strips is really minimal, while the loss from having more renderops is large.
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Post by sinbad » Wed Mar 30, 2005 1:55 pm

Strips only give you a major benefit on cards with little or no vertex cache, or when VRAM is at a serious premium that saving index buffer space is worth it (read - PlayStation 2). Beyond that, it makes little difference - a test I did even showed strips to be slightly slower than lists when rendering lots of terrain patches.
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Post by Marc » Wed Mar 30, 2005 8:15 pm

That's good to know. Thanks for all your replies. :)
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Post by NoNameVN » Wed Mar 30, 2005 10:05 pm

Actually tri-trip is not so good as rumors said. :)
You could refer to http://research.microsoft.com/%7Ehoppe/ (Vertex cache series) for more information.
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