Hi Gwyn, Thank you for the avatar draw weight resource links!
Best, Kay On Wed, Aug 29, 2012 at 11:45 AM, Gwyneth Llewelyn < [email protected]> wrote: > Dear Kay, > > You might wish read how Avatar Draw Weight is calculated: > http://wiki.secondlife.com/wiki/Mesh/Rendering_weight > > Base calculation is indeed linked to the number of triangles an avatar > has, and, of course, any attachment will add to that value. But extra > settings like glow, flexi, and some scripts will add even more. > > But remember: except for scripts on attachments, Avatar Draw Weight is a > measure of *viewer-side *lag, i.e. how big an effort *your* graphics card > has to make in order to render an avatar, and *not* an impact on the * > server* where OpenSim is running. While an avatar with tons of > attachments needs to download them first — which will create some impact on > the simulator, as it starts sending all that data to you; the more avatars > with attachments on the region, the more effort the simulator has to do — > after they're fully loaded, they should have no impact on the simulator any > more (attachments are phantom). Scripts, of course, running server-side, > are a different story. Scriptless attachments should not make a huge > difference on the simulator (except during the initial load). > > On the other hand, viewers will definitely notice the impact of high draw > weights. This is mostly noticeable on low-end, old graphics cards, which > cannot process so many triangles per frame. It's not so easy to find specs > for each and every card out there, and to know where the threshold is. > Modern, high-end graphics cards can render so many polygons per frame that > I would seriously suspect that they would not notice much of a difference. > > A simple rule of thumb: Draw weight of 1000 = just the standard avatar = > 7500 triangles > Everything above 1000, divided by 5, gives the amount of extra triangles > (assuming no glow, no flexiprims, etc.) So an avatar with draw weight of > 25,950 would have at most 12,500 or so triangles. 18 of those would come up > to 225,000 triangles. As far back as 2001, high-end graphic cards would > easily handle 60-100k triangles per frame, assuming 30 FPS ( > http://www.gamedev.net/topic/55764-how-many-triangles-do-most-computer-games-render-per-frame/). > In 2004, 400-500k triangles at 30 FPS seemed to be more typical ( > http://www.gamedev.net/topic/253770-how-many-triangles-can-your-engine-handle/ > ) > > Raz Welles has a thorough explanation of where all those triangles come > from: > http://razwelles.blogspot.pt/2012/06/opensim-and-mesh-understanding.html He > quotes a "typical" graphics card being able to render 1.5 million triangles > at 33 FPS. His articles is from June 2012, so you can see how the amount of > triangle rendering per second has been growing steadily in the past decade. > > Still, all these numbers are merely a rough guideline. LL's own engine on > the viewer might have performance limits as well — i.e. it may not be able > to send all those triangles to the OpenGL layer quickly enough for the GPU > to tender them. OpenGL, in return, also has a limit on how many triangles > it can send. And finally, these counts are usually for untextured triangles > — add texturing, and the number obviously drops! > > However, I think it's a relatively safe bet that anyone with a graphics > card of around 2010 or so should easily view those 18 avatars with Avatar > Draw Weight of 25,950, as easily as if they had no attachments, and still > get 30 FPS, if they don't turn on shadows or the more sophisticated > advanced lighting options on the newest viewers. > > I hope this helps. > > Cheers, > > - Gwyn > > On 29/08/2012, at 16:18, Kay McLennan wrote: > > OpenSim-User List Serve Colleagues, > > I currently use the Zen and Phoenix viewers (3) and noticed how the > "avatar draw weight" feature in these viewers reveals a dramatic increase > in my draw weight whenever I add any attachments to my avatar (read: prim > hair, face light, sculpt shoes or clothes, etc.). More specifically, > without any attachments, my avatar has a draw weight of 1,000 but with the > above listed attachments has a draw weight of 25,950. Further, when I was > at an [OpenSim] in-world meeting last week, I observed how many of the > approximately 18 avatars in attendance had even higher draw weights. > > What is the significance of the avatar draw weight when it comes to region > performance and lag? More specifically, if a region can support 18 avatars > with fairly high draw weights, could the region support double the number > of avatars if everyone used an avatar than only had a draw weight of 1,000? > > Thank you in advance. > > -- Kay McLennan > > > > -- > > "I'm not building a game. I'm building a new country." > > -- Philip "Linden" Rosedale, interview to Wired, 2004-05-08 > > > > _______________________________________________ > Opensim-users mailing list > [email protected] > https://lists.berlios.de/mailman/listinfo/opensim-users > --
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