Danny Nolan, breast physics coder; inset, the Emerald menu option he pioneered
The rise and fall of a female breast may seem like the most basic thing, but as it turns out, trying to simulate it in a virtual world is not all that easy. So when Danny Nolan and other programmers tried to add realistic physics to avatar breasts as a feature in Emerald, an open source Second Life viewer, they were sometimes stymied in strange ways. In one trial, adjusting the breast physics seemed to create spikes that burst out of a test avatar. Other times, the bouncing motion of the breasts somehow made a giant hole where the chest should be. (A bug the Emerald team is still trying to fix.)
The thing is, when the human breast meets Newtonian mechanics (or a virtual simulation of same), it "involves quite a bit of math," as Emerald lead developer Skills Hak puts it. "We were discussing the math behind it almost daily, and fixed a lot of bugs it created." (Trigonometry was brought to bear.) But Emerald's breast physics worked sufficiently well that they were added last week to the viewer latest build.
How does it work? In actuality, a limited form of breast physics already exists in Second Life, but it's only available in the avatar adjustment menu, as a "buoyancy" option. "I simply did the math in calculating the physics itself... to simply visually show it," Danny Nolan explains.
"It's basically just modifying the breast buoyancy slider in realtime, fully client-side," as Ms. Hak puts it. That means the breast physics are only viewable to someone who's running Second Life with the Emerald viewer, and has enabled that option. From the world's point of view, however, the breasts have not changed. (Which suggests a unique metaverse twist to the old philosophical conundrum: If a virtual bosom heaves in a Second Life forest, but only you see it on your monitor, does it actually make a jiggle?)
Emerald was already the most popular third party SL viewer before the breast augmentation, but since it was added last week, it's been in even higher demand: "Downloads for our latest release are over 50,000 already," Skills Hak tells me. "We switched over to hosting at google-code in the meantime though (because people were literally DDOS-ing our server with download requests) so it might be well even more." With roughly 750,000 active users, that means about 6% of the Second Life population now has access to Mr. Nolan's breast enhancement. Or to put it another way, if you have a female avatar, and you're at a Second Life event with 16 other Residents, chances are that one of them is able to watch your bosom bounce in a way you may not have intended.
Which suggests a problem that often happens with the social contract of Second Life, when technical ability crashes up against user consent. In this case, what if you have a female avatar, and you don't particularly like people watching your virtual breasts moving in a way you didn't choose?
"I heard it caused some controversy," Ms. Hak acknowledges, pointing me to a wiki page the Emerald team created to document that fallout. (And while the Lindens just announced they'll suspend the use of third party viewers which violate the company's Community Standards or Terms of Service, the Emerald viewer's breast physics don't seem to break any of those restrictions, at least not in any obvious way.)
For Danny Nolan's part, he mentions no salacious intent for making breasts look more physical: "One day I thought, "With SL being open source, how come nobody's written proper breast physics?'... after a while it just sorta became a personal quest, to see if I could actually manage to code it." (For those wondering, Mr. Nolan describes himself as male in real life, though his avatar is decidedly female. "Not particularly cause and effect, but it definitely made it easier to test while developing [breast physics].")
Still, his innovation has attracted critics.
"I did expect it," he tells me. "It really just started off as just me messing around with code, and then the Emerald teach contacted me and wanted me to add it in to their client, so suddenly what started off as a quiet little project ended up going to several thousands of people. And, with the 'subject matter' of the physics, I definitely expected some people to not want it. But that's why we gave the option of turning it off, or increasing/decreasing the effect. Totally optional."
"Well," I say, "women avatars don't have a choice if Emerald users are looking at their breasts becoming bouncier, right?"
"That's true actually," Nolan says. He says the Emerald team is working on adding an opt-out option, so female avatars can designate their breasts to remain in the state their owners intended them. "For those who want their privacy." Trouble then, Nolan adds, is other Emerald owners will complain about not being able to see breasts as they want them seen. (That is, to seem more realistic.)
"So, it's hard to find settings that'll please everyone," Danny Nolan says. "But we are definitely looking into other options to try and please as many people as we can."