TITLE: The Lilypond
NAME: Maurizio Tomasi
COUNTRY: Italy
EMAIL: zio_tom78@hotmail.com
WEBPAGE: http://www.geocities.com/zio_tom78
TOPIC: Spectacular Landscapes
COPYRIGHT: I SUBMIT TO THE STANDARD RAYTRACING COMPETITION COPYRIGHT.
JPGFILE: mtlily.jpg
ZIPFILE: mtlily.zip
RENDERER USED: 

    POV-Ray 3.5 for Linux


TOOLS USED: 

- Red Hat Linux 7.3, kernel 2.4.18 with KDE 3.0.0
- Emacs 21.2.1 in POV-mode
- The Gimp 1.2.3
- HeightField Lab 0.90 Beta
- Gilles Tran's MakeTree macro


RENDER TIME: 

Time For Parse:    0 hours  7 minutes   1.0 seconds (421 seconds)
Time For Trace:    2 hours 14 minutes  45.0 seconds (8007 seconds)
    Total Time:    2 hours 20 minutes  28.0 seconds (8428 seconds)

    
HARDWARE USED: 

    AMD Athlon 1000 Mhz with 128 MB RAM.


IMAGE DESCRIPTION:

      Once upon a time (before 1930s), ponds were quite common in the
Po valley (Northern Italy).  At that time it was possible to observe
the starred sky in a beautiful and peaceful landscape without being
disturbed by the city lights, not yet as bright as today.  This scene
takes place a bit after the sunset, when the moon is throwing shades
of gray on the Earth and still faint shades of orange appears at the
horizon.

      This is not a majestic image, but I think it suites well the
topic: my opinion is that a landscape has not to be necessarily solemn
in order to be "spectacular" and "stunning".  I hope you agree with
me.

      You could have some problems in seeing the image because it is
quite dark: if so, adjust the brightness of your monitor.  I already
increased a bit the brightness with The GIMP in order to see the
details on the monitor I am using at the University (the original
image is in the zip file, mtlily-original.jpg).


DESCRIPTION OF HOW THIS IMAGE WAS CREATED:

      First, a bit of history.  I must admit the topic was not very
interesting for me.  It is a bit too much "precise" in defining the
subject and does not offer many ways to be original, so at first I
thought not to participate to the IRTC.  But a month ago I found some
beautiful photos I took during a trip in the Alps last year.  A
waterfall with a small pond near it caught my attention, and I decided
to create a ray-traced image of it: this would have been a good
starting point for a IRTC submission!  But the task was not so simple:
I discovered that creating a realistic waterfall is a *real* pain.  So
I switched to a bunch of waterlilies in a pond.  My first idea was to
create an impressionistic picture by placing a transparent mirror with
some bumps on it in front of the camera: with some experiments I hoped
to get a good imitation of Monet's painting style.  But after about
50% of the image was done, I found that somebody else used the same
technique in the old "Gardens" round of IRTC! (sorry, I have forgotten
the name).  Since I already created the waterlilies, I decided not to
completely change the topic of the image and started modeling the
current scene.

      At first I thought to use a foggy weather (I do not like bright
images very much...), but after having rendered some test images I
found that a soft moonlight would have given a more impressive effect.
The most difficult issue was to choose the right set of colors:
landscapes under the moonlight are made almost completely by shades of
gray.  The actual result has perhaps too much colors, but I did not
want gray waterlilies! (an "artistic" alternative would have been to
create a grayscale image with the waterlilies being the only colored
things, but this would have been a bit off topic because of the lack
of realism...)

      The waterlilies are simple CSG objects made with intersecting
spheres.  The leaves under them are height field objects based on a
image (lily-leaf.png) I created with The GIMP (using the "smudge" tool
and a lot of Gaussian blur).  The land is an height field made with
HeightField Lab 0.90 and the aid of The GIMP to create the pond
depression (see make-hf.scr file).

      The grass and the reeds are sphere-sweep objects created with the
same macro.  The color shades and the mean height are determined by
two height field, grass-color.png and grass-height.png (created with
HeightField Lab; see the TraceGrass macro in grass.inc for details).

      Trees are created by running createwillow.pov; this uses the
excellent Gilles Tran's MakeTree macro to create three different trees
(actually they do not resemble real willows...).  I tried to write a
macro for creating weeping willows by using a lot of small spheres,
but the result was unmanageable because of memory requirements: a
barely acceptable willows came out from 115,000 spheres!  A week ago I
resigned and switched to Gilles' macro: now the whole image with five
trees is made by only 75,000 objects (and most of them are grass
blades!), although they do not look like willows.  The barks are
texture maps with a bump map created from the same texture with the
aid of the "emboss" filter (The GIMP).  Ok, within this size it is
hardly noticeable, but when I rendered close-ups of the trees, it gave
a very good effect.

      The water is a simple isosurface.  Note that a `USE_QUICK_WATER'
variable is commented in lilypond.pov: by uncommenting it the water
will be a box with bozo normals (quicker rendering, and probaby the
same quality). In order to improve a bit the light fade under the
water, I added a black fog under the water level.  This adds some good
detail to the image.

      The sky is a sky sphere with three layered textures.  A vertical
gradient from orange (at the horizon) to black (at the zenith)
suggests the sunset.  The second texture is a starry texture (a
modification of one of the textures provided in stars.inc, with less
colored stars).  Finally, a bozo pink texture suggests faint clouds
illuminated by the last shades of the sun.

      For the final rendering, I used an adaptive recursive
anti-aliasing with a very low threshold value (0.05) and a recursion
limit of 2 steps, in order to get a very smooth image.

      The included zip file contains every file I used to create the
image.  There is also a Makefile (GNU Make) which *should* let you to
re-create the image.  If you encounter problems, fell free to contact
me via e-mail.

Maurizio Tomasi