Virtual Fire

This article is reprinted from my Virtual Nature blog on September 20, 2006. Added text is italicized.

Fire is a necessary element to our real lives and utterly destructive when uncontrolled. We represent flame in virtual worlds for the sole purpose of seeing it as we cannot feel or use its heat. This elemental tie is either somehow beneficial to us or simply displays our lack of imagination. I suspect the former based on the fact that the representations generally seem to be used to create a mood. We build the fundamental appearance of something vital to our first lives and throw it into a corner as window dressing for our virtual lives. Is this what people mean when they say that Second Life is a “better world?”

Practically, builders do usually strive to enhance the appearance of a blaze by integrating static prims or adding surreal, colourful effects. The two methods of presentation are animated textures on prim faces and particle productions. The pictures above and to the left below demonstrate animated flame textures on prims and the use of solids to enhance the appearance of roaring, eternal fires. The pictures below displays the use of particles to simulate a burning effect. Note that the particles don’t lend a realistic appearance of flames. Particles can, however, be produced in randomly changing numbers, react to the wind vector, and shift their colouring to the extent of producing a smoke-like effect before dissipating with much less scripting and lag causing demands than their animated counterparts. Particles can now be rendered 8192 at a time, twice the older limit of 4096. Many people choose to set their viewable particle count to a lower value, or off altogether, to avoid client side lag.

Some other combustions I’ve witnessed in Second Life are bubbling volcanos and geysers. Randomly timed eruptions contribute a wonderfully natural atmosphere to any area. There are of course those timers dragging down the regional processor; but that technology is steadily improving. One day we’ll be able to place markers in a sim that tell clients to download and represent objects whose scripts are being processed on supplementary servers. Then we’ll see some very realistic representations of natural effects. Picture alignment is a nightmare using Wordpress. If anyone has tips or ideas of how to better manage this site’s style sheet, your input will be much appreciated.