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Moriash Moreau: My Second Life
Tuesday, September 11, 2007
 
The Skies of My Youth
I had some spare time a couple of evenings ago, so I decided to fly up to a trillion meters or so. I've done this kind of thing before, but I thought I'd see if the current version of high-altitude Second Life has anything new to offer.


There was nothing special about the apparati used. I used a total of 38 attachments (all 30 attachment points, and all eight HUD locations), each one housing five scripts. Each script applied the maximum upward force (llSetForce) allowed by LSL (MAXINT, or 2,147,483,648, in who knows what units of measure), as well as an upward push (llApplyImpulse. again at MAXINT) four times a second. When in use, the small cubes shown grow to 10 meters across, allowing for maximum force (maximum push strength is proportional to object mass) and energy reserves. (There's probably an optimal balancing act between size, force, energy recovery, etc. And, of course, I could use more scripts. This works well enough, though.) A trivially simple, brute-force approach, multiplied a ridiculous number of times.


Here are closeups of the client camera HUD info and task bar altimeter. The trip took about 27 minutes, at a speed of 617,283,950 meters per second. And, in spite of travelling at over twice the speed of light, it was one of the more boring experiences I've had in SL. Beyond the knowledge that you're moving at 2c, there really isn't much else to recommend the trip.

Once your avatar passes a million meters, it disappears. I'm not altogether certain why this happens, actually. It's not a gradual effect, like the "av-melting" effect, nor does it happen at one of the programmer's totemistic powers of two. Very odd.

After that, you're left with a monotonous view of the SL sky. Soon, you're robbed of even the ability to pan your camera up or down (either in third person or mouselook), as the necessary coordinates for camera position/focus are moved out of range by floating point rounding errors on the Z coordinates. Other than that, the only entertainment is the occasional flickering of the sky to black. Really quite annoying, actually.

Incidentally, note the client altimeter. It's apparently limited by MAXINT as well. In order to get altitude readings, I had to switch on the client camera HUD information. That appears to work just fine at whatever altitude, although it does jump from rounding point to rounding point as you get higher.


It wasn't always this way. Up until sometime late last year (I'd guess sometime around when the new sun appeared in the sky), there were all sorts of interesting effects. And, of course, your avatar stayed around for considerably longer, melting and jittering all the more as you flew higher and higher.

Addendum, 9/30/07
Historical Note- Based on the one weblog entry I can successfully Google (news about Sun Microsystems and the abbreviation for "Sunday" effectively mask the obvious search keywords), the new sun probably appeared sometime in late April or early May of 2007. I can't confirm, but I still believe that this is probably when the sky effects disappeared. I expect Windlight preparations are involved in this somewhere, as well. I dearly wish I'd thought to photograph the old sun in detail, for historical interest. It had some interesting (if static) sunspots. Alas, nobody thinks "I'd better photograph the sun, it may change someday." A good lesson about the ephemeral nature of just about everything in Second Life.


The shot above, and the ones that follow, were taken in September and November of 2005, using a considerably more primitive booster assembly. As I remember, the trip to a mere billion meters took several hours. For a few hours of that (while I slept), I used a macro recorder to periodically move my camera in prescribed ways (mouselook, up, down, horizon) and press the snapshot key for me. I always meant to take some more formal pictures to document it all, and perhaps even take some video footage, as well. But, alas, time got away from me and the technology changed. And now, all that's left is a few thousand (yes, thousand) unsorted snapshots.

I'm not certain what caused the red hue shown above, as it was one of the pictures taken automatically. I'm guessing some kind of bleedover from a sunset and the distorted horizon. I have a few snapshots like this, some of which are completely red. Very odd.


This is a shot of an interesting effect that kicked in at around 100,000 meters, and progressed until 105,000 meters. Initially, a small, jagged black hole would appear directly above the avatar (no matter where he was). As the avatar rose, the hole would get larger, progressing in a series of wide, blocky bands that faded from deep blue to black. Finally, the entire sky, all the way to the horizon, would be swallowed. Quite an ominous effect. As I remember, the sky would eventually invert itself at higher elevations, and the effect would repeat in reverse. This repeated at intervals for a few hundred thousand meters.


Another shot of the hole in the sky, from a couple thousand meters further up.

I suppose I should mention that the grey avatar was my choice, and not due to any particular elevation or asset server effect. If I remember correctly, I theorized that it would be easier to discern elevation effects on the avatar if details weren't obscured by clothing and skin textures. I wish I'd taken more pictures with a real avatar in frame, now.


I always liked this effect. This is a shot with the sun at the "sunset" position, taken just before the hole above completely swallowed the sky. Very pretty. I used this effect in a Plywood strip, without even thinking about how few people would have actually seen it first hand. Now, I wonder how many folks were confused by it.


At high vertical speeds, the blending at the edges of the sky tends to break down. Turns out the sky is a giant cube with the textures painted on. "For the world is hollow and I have touched the sky..."

This effect is still somewhat visible today, but it used to be considerably more so. Generally, it is most apparent when travelling upward at high speeds and turning (clockwise or counterclockwise, doesn't seem to matter which). When you stop moving, the edges will stay for a moment, then blur back into an apparently seamless sky.

Note the chat readout for my old boosters. It would announce the speed and altitude every ten seconds. Pfft! Only 640 meters per second! Note also the llSetText from my Terra Warp belt. It should be floating above my head, with two lines of text. Floating text is affected by the same floating point errors that cause melting avatar meshes. llSetText became unreadable at a few million meters up, as it snapped several meters up and down ever second. And I've noticed a bit of jitter even as low as a couple thousand meters.


Occasionally, odd effects would appear as the sun moved across the sky. Sometimes, if you watched a corner, you could see perspective errors that revealed the sky was painted on a flat plane at an angle to your camera.


Another sky painting glitch. These generally only happened at very narrow altitude ranges, and were dependent on current sun position and camera angle.


An unusual solar eclipse effect at 205,000 meters, with the sun at the sunset position. The sun isn't just blotted out, it actually inverts to black and charcoal. My suspicion is that it was blacked out as a method of concealing it when it passes under the horizon. Normally this would be hidden by the ground, or the fog effect as the ground passes out of draw distance. Not so here, for some reason.

I may post more pictures later, when I finish sorting through them all, but this is a pretty good overview of most of the sky effects that have now passed into SL history. I'm sure that the new sky is part of Linden Lab's efforts at increasing stability and fixing bugs. And if the only sacrifice is the loss of a couple of pretty glitches, I'm all for it. Still, I kind of miss having a secret world only a few thousand kilometers above me.

Oh well, bring on Windlight. We'll see what it looks like from above.
Monday, September 10, 2007
 
Visit Scenic 1,000 Kilometers!
If anyone is interested, I've setup a semi-permanent Av-Melter stand in Abitibi (SLURL link). Just thought I'd mention it after Daedalus Young's recent documented flight to a million meters, and its subsequent mention in the Linden Blog. Wish I'd thought to take videos before somebody beat me to the punch. Ah, well.
Tuesday, September 04, 2007
 
Tempest. Teacup.
This isn't strictly SL-related, but it seems like every time any new SL controversy comes along, someone gets it wrong.

The phrase is "a tempest in a teacup." Not "a storm in a water glass," or a "hurricane in a coffee mug," or even "a tropical depression in a champagne flute." It's "tempest in a teacup." It's alliterative. Tempest. Teacup. Sometimes, it's "teapot." I can live with that, although it's definitely not the more common usage.

"Oh," I can hear you say. "Oh, but Mori, I've heard/read it as 'a [storm synonym] in a [drinking vessel]!'" Well then you've heard it wrong!. Tempest. Teacup. That is the phrase.

Tempest. Teacup. So sayeth Mori.

Just had to get that off my chest. Thank you.
Monday, September 03, 2007
 
The Case for Immersion #3
It's been a long time since I've documented a moment of immersion. They've been few and far between. But one occurred Sunday morning.

Friday evening, I spent a not inconsiderable amount of time searching for my first prim hair, then carefully fitting it onto my avatar's newly-shorn scalp.

Sunday, I watched as my mother carefully fit a new wig onto her own head, which is going bald due to chemotherapy treatments.

For a moment, the two realities blurred. All told, it was a moment of immersion I really could have done without.