TITLE: A cold, Dreary Day
NAME: Michael Raiford
COUNTRY: USA
EMAIL: mraiford@coserv.net
WEBPAGE: none
TOPIC: Winter
COPYRIGHT: I SUBMIT TO THE STANDARD RAYTRACING COMPETITION COPYRIGHT.
JPGFILE: coldday.jpg
ZIPFILE: coldday.zip
RENDERER USED: 
    POVRay 3.5 beta

TOOLS USED: 
    GIMP (for conversion to JPG), POVWin's text editor, LParser for the
trees. 

RENDER TIME: 


HARDWARE USED: 
    Pentium III 866

IMAGE DESCRIPTION: 


It's a cold winter's day. Everyone is inside, keeping warm. The heat from 
the house has melted some of the snow on the roof, creating icicles.


DESCRIPTION OF HOW THIS IMAGE WAS CREATED: 


Well, It's been a while since I've done anything with POV-Ray, but since 3.5 is
out, I
decided to jump back in. As I read the topic, "Winter". Wow, almost spring, and
they want me to think of winter. Well-- whar epitomises winter? Gray, dreary
skies, ice, snow. An idea was born: Something that had dreary skies, ice, and
snow! --But, it had to feel cold, too. More on that, later. 

This scene is a create experiment with SDL and 3.5's features. 

To start, I made a sketch of what I wanted. Bascally, I wanted to look down the
side of this house, and see the warm light coming through a cold, frosty,
window. Once the sketch was in order, thinking about how I'm going to turn the
sketch into a scene. 

First things first. Lets get the snow out of the way. 

A heightfield was a logical choice for this. So, I sat, and thoght about a way
to make smooth, flowing drifts of snow. Bozo seemd like a shoe-in for this. So,
I used the bozo pattern to create the image for the heightfield. 

On to creating the house...

Any building is basically a box, slap some brick texture and with the small bit
of the house we'll be seeing, this make a convincing house. Without  a roof.
The roof is basically a box, turned 45 degreed and sliced in half along the XZ
plane. The shingle texture is just bricks, and the melted snow on the roof is
another heiht field. 

I love how the snow on the roof turned out, it's bascially a bozo pattern used
to reveal a ripples pattern with a little bit of turbulence. It worked
beautifully for creating the snow on the roof. 

I then added a block, with a normal of wood, and placed it under the edge of the
roof on the side the camera was going to be on. 

At this point the house was placed at the edge of the heightfield, to give a
good view of the snow that has fallen. 

I then chopped out a hole in the side, hollwoed the building, and added a
light-source inside the house. and spent a couple hours trying to figure out
why my difference had speckles, as it turned out, the lightsource was on the
surface of the roof, causing the shadow tests to come back with random shadows.
Great, now I have a hole with a light inside. What it needs is a window. What I
needed was a chance to test out some of the more advanced SDL stuff that I've
never tried. So I used loops to create the dividers and panes for the window. 

The window is made of 8 thin dividers and 9 panes. I get another chance to play
with some 3.5 features... I wanted each pane to be slightly frosted. I
considered using wood for this, but wood didn't look like I wanted. I wanted
something like a box with rounded corners. A superellipsoid, so I used the
superellipsoid internal function to create the frosting effect on the window
panes. 

With the window in place, the soffet, snowy roof, and textures in place, it
looked like a small cottage. Great!

Then, I started thinking about the icicles. This was the main focus of the
picture, and I wanted them to look somewhat convincing. Icicles are basically a
cone, but slightly perturbed. Possibly by a noise function?

So, I used an isosurface to create the icecicles. The toughest part was keeping
the noise from being stretched with the scale, so I created a macro to create
an icicle. scaling the values passed into the noise function by the length
scale I gave the icicle. Each one is randomly generated along a line, and the
whole unit was textured, and moved into place. 

The iciles didn't look right, something was missing.... so I added a sheet of
ice to the soffet, it's just a very thin box, with a bozo normal on it. (the
icicles had to drip from somewhere, right?)

The scene was complete, but It was missing something. Trees! Outdoors has
trees!. So I fired up LParser, took one of the many sample tree files, and
generated a tree, placed it randomly about the scene, and left it at that.
Yeah, the trees are green. I don't know lparser that much to strip the leaves,
and the output is a little large to hand-pick through, so imagine they are some
sort of live-oak. 

This was a fun scene to work on, and it lent itself easily to a few of the newer
POVRay features. 






