TITLE: Rainbow Bridge
NAME: Leroy Whetstone
COUNTRY: USA
EMAIL: lrwii@joplin.com
TOPIC: Spirit of Asia
COPYRIGHT: I SUBMIT TO THE STANDARD RAYTRACING COMPETITION COPYRIGHT.
JPGFILE: rainbow.jpg
ZIPFILE: rainbow.zip
RENDERER USED: 

Povray 3.5.7-8  Windows


TOOLS USED: 

 jpeg convertion: iPhotoPlus
  Triangle mesh: David Sharp



RENDER TIME: 

 Parse: 4 sec. 
 Trace: 12 hour 35 min. 51 sec.



HARDWARE USED: 

Anthon 1.2Ghz 128 Meg RAM


IMAGE DESCRIPTION: 


The ancient Rainbow Bridge of China remade today. 


DESCRIPTION OF HOW THIS IMAGE WAS CREATED: 


 This is my tenth entry. When I first heard of the topic I got on the internet
and 
 looked up Asia. It seems no one agrees on just what Asia is. Some web sites
included 
 Saudi Arabia, some not, some included Russia others didn't. One site even
include
 Australia?! I found one site that had Asia divided up into several smaller
regions,
 like; Eastern Asia, Middle Asia and so on... I had in mind of taking one item
from  
 each of these regions and putting it on a table. But I didn't get very far
before
 I lost intrest. It was to much leg work. Then I remember the China's Rainbow
Bridge.     
  I had seen NOVA's program on PBS where they recreated the Rainbow Bridge. I
went to
 their web site for reference material. I didn't find plans. 
 I just worked from the pictures on their site.
 
 Nova's web site: http://www.pbs.org/wgbh/nova/lostempires/china/builds.html
   
  
SCENE :
 size: 800 * 600  
 focal blur aperture .7 samples 100
 radiosity : copied from 'Radiosity with conventional lighting' in help files
             with the brightness changed to .5  
 frame level objects: 2635

Objects:

 The BRIDGE: The structure under the bridge was the first thing I tackled. It
basically
            just a group of cylinders. But the hard part was getting them placed
where
            they are just touching the cross members while getting a good span
and height.
            Using radiosity, I had a little trouble getting the side by side
cylinders to
            show up. Until I put a little reflection in their finish.
     Rails: There are 5 of them counting the base. They where made using
'sphere_sweep'
             and intersected with a box. As was the side boards. I made a macro
with
             the basic shape and the radius was variable. The top two rails are
thicker
              than the bottom two.
     Steps: this was the first time I used 'trace'. The way I use it was I made
an 
              object with the previous macro and place it in the middle of the
bridge.
              Then I started the trace at the bottom and incremented the trace
every .5 POV
              units making a box that would use values from the pervious trace
with the 
              current trace to form it.       
  End Posts: there 4 on each end, each are an union of two boxes with a 
                   'Rounded_Box_Union' from Shapes.inc on top
Middle Post: These where trouble. There is two parts to each. The lower part had
to be
              cut off for the second rail and a smaller part had to fit the top
rail.
              The lower part was done with a large sphere_sweep (using that
macro)
              intersected with a Box. The upper part was done by intersecting
two boxes. 
Post brackets: These are hard to see, they're a box tilted in the x and y
direction and
              placed manually. They start just below the second rail and end on
the
              what I call the face board. I try a lot of things to get them to
show
              up more and finally settle for what I used.
 
 Lights: 1 White place far above the ground  

 Sky: a skysphere with a very simple color map
             
 Water: my first use of ISO surface. I used the wrinkle function. I'm pleased
the way it
       turn out. But the ISO surface in the far background looked pretty bad. So
to fix it
       I put a box tilted at a very small angle and highly reflective with a
bozo normal
       down to where it would slowly cut of the ISO surfare's peaks, then cover
it completely.   
       It made things even better.  

 Near Banks: these are rather simple, lots of boxes and cylinders
 
 Far banks: These are more complicated I used ISO surfaces for the Blocks and
steps,
           boxes to fill in holes and Black boxes behind the Blocks to add
shadow.
           I use layered textures to get the water line.

 Buildings: I placed all the boxes by hand. For the roofs I made another macro.
It places
           cylinders side by side of a particular length in a union. I use a
neat little
           'gradient z' pigment to give the roofs that tile look.
           For the gables I hand made triangles. 
           The windows are just boxes with a black and white pigment using
'bozo' pattern
           I tried using reflection with Photons but it didn't turn out any
better.
 
 Trees: the limbs are 'sphere_sweep'
        the leafs are made of triangles and placed randomly using 
         'VRand_In_Sphere' in 'Rand.inc'

Zip-File: Rainbow.pov 
   
   This zip should contain only one file. Any inc files I had I copied their
contents 
   into progarm. If you have 3.5 beta 7 or better then everything should work
for ya.
            
Epilogue: This is the first picture I've enter using Radiosity. I never got into
the habit
         of using it because it was too slow on my old computer. I like what it
can do.
         I'll use more of it. 
          This picture is also has the longest render time I've every done. I've
just
         upgraded my computer to 1.2 ghz. I'm have the strange feeling that if I
keep 
         getting faster and faster upgrades then one day it will take forever to
render 
         the finish picture.
         
         
          Feel free to E-mail me with any comments and or suggests.





