In last week's NWN tech forum on fixing Second Life lag, ex-Linden Lab developer Karl Stiefvater argued that meshes would be a giant boon. At first I was skeptical, but a Resident named Followmeimthe Piedpiper (oh yes) sent me these two compelling visual illustrations:
"The first shows a normal cubic prim rendered in Second Life as a wireframe." (At right.) "Without any cut sides or hollows it still uses 56 vertices. All these need computing to rez." That's a lot of excess machinations, because by contrast, "A normal basic real life 3D cube in comparison only has 8 corners." Mr. Piedpiper went on: "Now compare a simple wall with two offset window holes in it." (After the break.)
"Made from prims it needs a minimum of 6, adding up to a whopping 6x56 = 336 vertices. (Shown as the blue dots.) The same wall made from a mesh by punching two holes in a box uses 24 vertices."
I checked this demo with Karl (now known in SL as Qarl Fizz, and an Emerald viewer developer), and he confirmed this checked out: "Yup -- he's right on the money." So when meshes are enabled in Second Life, and gradually become more commonplace, basic mathematics suggest lag in SL will decrease. Of course, meshes are only expected to make it to Open Beta later this year, it's unknown when they'll ship to Second Life proper, and it'll probably be a year or more for meshes to gradually supplant prim-based creations. What to do about lag in the meantime? I have an idea, but that's for another post.