TITLE: frosted
NAME: Norbert Kern
COUNTRY: Germany
EMAIL: norbert-werner.kern@t-online.de
WEBPAGE: not yet
TOPIC: Winter
COPYRIGHT: I SUBMIT TO THE STANDARD RAYTRACING COMPETITION COPYRIGHT.
JPGFILE: frosted.jpg
ZIPFILE: frosted.zip
RENDERER USED: 
    Pov-Ray v3.5 RC2

TOOLS USED: 
    Xfrog, Poser, Hamapatch, 3DWin, Photoshop

RENDER TIME: 

1. image
parse 2 min 35 sec + ca. 28 h additional parsing for "frosting"
 trace 120 h (2048*1152 AA 0.3)  peak memory 731 MB

2. post processing (with Pov-Ray):
parse 17 min / trace 7 sec (1024*576; no AA) peak memory 663 MB


HARDWARE USED: 
    1,4 GHz Athlon C / 1 GB RAM



IMAGE DESCRIPTION: 


Waft of mist ascend from a quiet pond on a winter morning. 
Hearfrost covers withering plants together with the last dragonfly
while the sunbeams at the red morning sky are too weak to warm. 
Soon the pond will freeze too...

The scene is a makeshift because after one month of work my first
trial had to be delayed. My modeling skills are still too inferior...


DESCRIPTION OF HOW THIS IMAGE WAS CREATED: 


Main goals were to create a cold and lonely winter mood and to
make postprocessing within Pov-Ray in a second pass.

Trees and plants are modeled with Xfrog
(http://www.kurtz-fernhout.com/PlantStudio/) or are from the net.
The main parts of the dragonfly are from a poser model
(http://www.silverleifstudios.com/gallery/downloads.html);
dragonfly legs are modeled with Hamapatch 
(http://www.geocities.com/hamapatch/program/);
texture maps were changed with photoshop.
The original code of the grass on the island is from Mick
Hazelgrove (http://www.mhazelgrove.fsnet.co.uk/).

Atmosphere was created with a combination of emitting, absorbing 
and scattering media. As a starting point I played with the emitting media 
settings of  Nathan o Brian_s "13storm"
(http://oz.irtc.org/ftp/pub/stills/1998-08-31/13storm.jpg).

The sun is a mixture of an area light with emitting media and 
Chris Colefax Lnsefcts.inc 
(http://www.geocities.com/SiliconValley/Lakes/1434/lenseffects.html).

Vegetation is planted with my own method described earlier
(http://www.irtc.org/ftp/pub/stills/2002-02-28/meadow.txt).

Hearfrost is simulated with in total 84.000 tiny cigar shaped spheres.
They are "shot" with trace from random points on the foreground objects.
The next particle is shot on an union of the object plus the first particle
and so on. Since Pov-Ray can handle a maximum of "only" 16224 nested
objects, I saved the coordinates and angles of the frost particles in 
a seperate file and started the process again next day. 
The whole file generation needed 28 h for the three objects. 
One example of such a frost generation is included in the zip file.

The texture of the dragonfly integrated an imagemap, normalmap,
reflectionmap and a transparentmap in a single image_pattern based
texture. 

Since the normal Pov-Ray antialiasing methods are not perfectly suited
for very thin lines as in my entry, I wanted to resample a bigger render.
Since applying a mosaic filter and subsequent resizing could be seen as
post processing, which is not allowed by the IRTC rules, I made such
resampling within Pov-Ray.
Because it was easy, I integrated contrast enhencement and a gamma change
for each color component.
By now the method is simple, but very slow and needs huge amounts of 
memory.

The zip file does not contain the meshes because of their size and
the imagemaps are scaled down for the same reason.
The complete source has ca. 286 MB (62 MB zipped). 
If anybody wants it, feel free to contact me.