TITLE: Gila NAME: Douglas Eichenberg COUNTRY: USA EMAIL: douge@nls.net WEBPAGE: www.getinfo.net/douge TOPIC: The Wilderness COPYRIGHT: I SUBMIT TO THE STANDARD RAYTRACING JPGFILE: gila.jpg ZIPFILE: gila.zip RENDERER USED: POVRay v3.1, MegaPOV 0.5 TOOLS USED: Moray v3.2, NuGraf/PolyTrans v2.2j, Paint Shop Pro v6.02, MakeTree.pov by Gilles Tran, TrueSpace v4 RENDER TIME: 47m 6s HARDWARE USED: 600 MHz PIII/Windows 2000/128Mb IMAGE DESCRIPTION: The Sonoran Desert of Arizona, with native flora and fauna. The scene depicts a Gila monster hunting for eggs. GILA MONSTER: There are only two known venomous lizards: the Gila Monster (pictured here) and a close relative, the Mexican Beaded Lizard. Both live in the Sonoran Desert. Both lizards are of the same genus, which dates back 30 million years to the Oligocene epoch (a period of time between the dinosaurs and man). Over this 30 million year span of time, the Gila Monster has not evolved in any way; a skeleton from 30 million years ago is identical to one from the present day. Perhaps one of the most survivable creatures, the Gila Monster is able to live up to three years without food in one of the harshest environments on the planet. They live largely on the eggs of other desert animals, especially ground nesting birds (which are quite common in the desert). The Gila monster's sense of smell is so keen that it can smell a single egg buried six inches beneath the surface. OCOTILLO: In order for a tree or bush to survive in the desert, there have to be some ingenious survival techniques. The ocotillo reduces it's exposure to harsh sunlight by shedding it's leaves when it gets to be too dry (as many as six or eight times per year). In a place where not even weeds can grow, the ocotillo does pretty well. THE SOTOL PLANT: I couldn't find anything interesting to say about this plant, except that the Pima Indians used it for weaving because it has such strong fibers. ROCKS: In scientific terminology these are called, um, rocks. DESCRIPTION OF HOW THIS IMAGE WAS CREATED: The cracked desert floor is a height field created in POV with Moray and converted into a tileable bump map. The beauty of it is that you can't tell it's tiled unless you're looking for it. The bump map image is a gray scale TGA. To get the color you see I applied a semi-transparent crackle-patterned colormap over top of the bump map. The rocks came from a macro I wrote based on Jaime Vives Piqueres code for his image 'running' in the September/October '99 round of the IRTC (one of my all-time favorite POV images... I use it as my Windows backdrop). The plants are also based on code from Jaime's image. Each plant and rock was individually placed (ie., the placement is not random). The tree is a modified Gilles Tran tree, created with his MakeTree.pov code. By increasing the initial number of branch segments and creating a push vector in the +y direction, I was able to create something that looked reasonably like a desert bush. I came up with a neat trick for lighting the scene. First I created a simple overhead area light parallel to the ground plane, making it shadowless. I was then able to tweak this light to adjust the brightness. Then I added another area light, tilted at an angle, to cast some nice soft shadows. At that point I was unhappy with the overall effect; the dark areas were *too* dark, and a lot of the scene just wasn't getting enough light. I've never liked to depend on ambience because I don't like the way it looks, so what I did instead was create a large hollow sphere and make a shadowless point light, attaching the 'looks_like' keyword to it. That gave me a large spherical light all around the scene, casting light into all the little areas that were otherwise missed. It's basically a nicer version of ambient light. Moving the sphere around has some interesting and subtle effects. Also, on the area lights I turned adaptive up to 3 to smooth out the shadows. Originally, the scene was coded and rendered with version 3.1. I decided at the last minute to add a motion blur effect to the tongue, so I ported the code to MegaPOV 0.5. This had a strange effect on the bump maps and other bumps, so I added the '#version official 3.1;' line at the end of all the files. I also had to tweak the following settings for the finish on the lizard: ambient, diffuse and specular. The resulting leopard surface normal looks much nicer in MegaPOV than it did in version 3.1. Technically, this shouldn't happen: according to the MegaPOV docs, adding the '#version official 3.1;' line to the end of all the files will cause normals to be done by 3.1 methods. Another weird MegaPOV thing: when the scene is rendered it generates a warning saying 'Camera is inside a non-hollow object.' (which isn't true). The lizard was modelled in TrueSpace and converted to a mesh of smooth triangles with NuGraf/PolyTrans (12.6 meg file). The orange and black pattern on the lizards skin is an image map with a leopard surface normal for scales. I tried some other patterns for the normal, but none of them looked quite right. Most of the include files and image maps have been left out because they're just too big, but I'll be happy to give a complete copy to anybody who wants one.