simulator bomb

A "simulator bomb" is an object or operation that causes the simulator to become unresponsive for a long time.

(I'm happy to report that most simulator bombs have been defused in the next release... the bug has been fixed! But in the meantime, here is some information about them...)

The symptoms of an unresponsive simulator are:

(1) Your avatar cannot move. It can look around, but it can't walk or fly. If you are already moving then you won't be able to stop and you'll drift forever.

(2) You can't create new objects. It might appear that you can move some existing objects, however they will probably not show up where you moved them when the simulator comes back up.

(3) Chat becomes sluggish or unresponisve.

(4) You no longer get any statistics updates from that sim (if you have the statistics bar up you might notice this).

(5) It the simulator has been unresponsive for a long time it might show up red in your map.

Here are some examples of simulator bombs in the past:

(a) Jane Lifer made a really neat house. It has walls, floor, roof, stairs, and fancy wall mounted lights made out of hollow, cut torri. Jane decides she likes her house just the way it is and links the whole thing into a single object. Then she selects the house and accidentally does a small shift-drag on one of the selection arrows, which makes a new copy ouf the house right on top of the original house --> deep think.

(b) Joe Lifer sees that Peter Lifer has made a really cool car and is selling it for a bargain. He decides to buy a copy which goes into his inventory. He then decides to drag a copy of the car into the world... but it doen't show up right away so he does it again, right where the first one was supposed to be... meanwhile the data starts to come in from the first car which fades into view... and the second car fades into view too... and it is selected. Joe accidentally deselects the car while it is still interpenetrating the first --> deep think.

(c) Jacky Lifer found a really cool scripted jetpack (made with lots of curvy concave cut, hollow torii) and decides to make three copies that overlap each other --> sluggish think. (this bomb is slightly different from the first two, but has also been fixed).

Simulator bombs are caused by complex objects being in a state of interpenetration that causes the physics engine to take a long time compute the solution. You can avoid making them by:

(1) Be very careful when using shift-drag on objects that have more than 10 linked primitives... especially when some of those objects are concave.

(2) When making copies of complex objects with lots of primitives... be sure to make the copies so that only a few (or none) of the primitives of each object are overlapping.

(3) If you think you have already built a simulator bomb and you want to deactivate it... if you select a part of it, be sure to move that part completel out of interpenetration with the other part _before_you_deselect_it_.

I hope this helps shed some light on some of the frustrating events in the world and to help everybody avoid making sim bombs. And of course, as I mentioned before, bombs as described here have been defused in the next release (which should be out next week!).