TITLE: "The Jumpers", jumpers.jpg NAME: Darin A. Nelson COUNTRY: citizen USA; resident, Israel EMAIL: darin@opt-imaging.com WEBPAGE: -- TOPIC: Frozen Moment COPYRIGHT: I SUBMIT TO THE STANDARD RAYTRACING COMPETITION COPYRIGHT. JPGFILE: jumpers.jpg RENDERER USED: POVRay 3.5 for Windows TOOLS USED: Moray 3.3, Chris Colefax's Liquid Spray Include File, Moray Liquid Spray Plugin v.0.14 (Keith Hull), PaintShop Pro V. 7 (.jpg conversion and copyright logo addition only), various custom utilities (see below) RENDER TIME: 96 hours, 47 minutes, 28 seconds. HARDWARE USED: Pentium 4, 1.7GHz, 256 Mb RAM IMAGE DESCRIPTION: Two bears can roll a bottle of water as far as necessary across a tiled floor; opening it is another story. Three are enough to transport a block, but carrying a hundred of them takes a while. Empty teacups require one teddy bear each to transport. Full ones, four. The bowl is delicate, but heavy: six bears. Six frozen moments: Moment of Enthusiasm, Moment of Regret; Moment of Hesitation, Moment of Recklessness; Moment of Contemplation, Moment of Confusion. DESCRIPTION OF HOW THIS IMAGE WAS CREATED: I picked this hobby up rather recently (and this is my first submission to IRTC), which, ah... shows in the process... as you shall read: (SOMEWHAT UNUSUAL THINGS) Bears: These are based on standard CSG. Note, however, that they have fuzzy outlines; and on the wet teddybear, you can see strands. The fur isn't made of cylinders, or of meshes, but of nested, partially transparent primitives for fur (5-7 layers), applied by a LabVIEW utility written for the purpose. Yeah, kind of an odd approach, but it helped the bears meet my "huggability" criterion. Apparently from ignorance of the proper tricks (see below), I couldn't get enough hair primitives in the scene file to keep the bears from looking like walking bottle brushes (the page file started ballooning above 100K cylinders), so I settled on this "poor raytracers' fur" instead. The technique is an extension of what has been seen before for giving depth to texture clouds and grass (see, for example, Rune Johansen's layering suggestion for using his grass include file at http://runevision.com/3d/include/include.asp). I seem to recall seeing a reference to "media fur" at some point, but this ain't that. I am (now) aware that there are other fur techniques beyond those I tried which might have served as well or better. For those few like me who might not be aware of them: Parameterized isosurfaces using textures for shape definition would have been another offbeat choice (see the POVRay isosurface tutorial for hints of what this might look like); a better approach seems to be the duplicated mesh technique used by the redoubtable Chris Colefax's Hair Growth Macro File, (http://www.geocities.com/SiliconValley/Lakes/1434/pcm.html). Bowl Water: After rejecting various hand-arranged efforts, I broke down and wrote an interacting smooth particle simulation for determining blob primitive positions (basically, slightly sticky bouncy balls with a need for personal space). Again, LabVIEW, so the source isn't of much general use. But see, e.g., http://www.cs.unc.edu/~nyland/nbody.html for a more detailed discussion of techniques for such simulations (I implemented the most basic simulation listed on this page). A second utility performed particle frame summation, addition of rotational turbulance, and conversion to POVRay script. The resulting fluid is a bit agitated; but trust me, the jumping teddybear is not being boiled. Simulated particles: about 1500. Particles in final blob: about 10,000. (NORMAL THINGS WORTH A COMMENT): Other Water: The puddles are bezier patches with curved edges to imitate water held together by surface tension. The wet teddybear has rings spreading from his feet; these are from cylinders with a ripple normal texture, with the endcaps aligned with the surface of the puddle patch. The spray is made using Colefax's nifty spray macro (this, I did discover before I'd DTTHW), under control through a Moray plugin written by Keith Hull. Blocks: Some of the letters on the alphabet blocks (aleph, bet, gimel) are in Hebrew, in case you were wondering. The solid colored blocks are based on a vague memory of the contents of the "Big Barrel O' Blocks" I had as a child (now marketed as the "Big Bag O' Blocks," apparently). Looking at them, I can almost taste the wood in my mouth. .JPG compression has all but obliterated the texturing on the red and blue blocks, but it was there, once. Ceramic ware: none of the patterning is texture mapped, it's all done by CSG (you can see the interior cuts on the bowl rim). Somehow this seemed classier to me . Floor: each tile is a separate object, curved at the edges. The grouting, significantly, is an infinite plane.