The Story Behind the 2005 Holiday Card

300x200 (50K) The image was created by a computer program that uses a computer graphics technique called ray tracing. I described the concept in last year's holiday card description.


(Click here for a 1200x800 image. [652KB, 1:30 @ 56K]
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The scene:

The scene is made up of objects that are modeled by geometric shapes.

wreath (11K)
Wreath

The stylized wreath is made from spiral shapes. If we take a simple spiral and attach its head to its tail, we have a torus. The wreath is made from several of these.
But all we have at this point is a path with no objects to appear in the image. To visualize the spirals and, therefore, the wreath, I placed small green spheres at regular intervals on the spiral. I connected the spheres by small cylinders to fill in the gaps. I duplicated the spiral twice and shifted their starting positions just a tad so the three of them seem to twist about each other. This added bulk to the wreath.
For the ribbons, I made another spiral with a slightly larger radius and not quite so many turns as the green spirals. This coil was duplicated and made to twist the other way to get the two red ribbons to cross each other.
The ribbons were visualized by using flat triangles instead of spheres and cylinders. Since triangles are flat, so are the ribbons.
The ribbon with the words is a free floating curve with flat triangles along its path. The words were "projected" onto the ribbon.

 

 

models (12K)
Door and window

The models of the door and window came from a modeling program called Trispectivestm: These detailed models were exported to my software which applied the finish textures and the tints to the glass in the window.
I added the Hamesh to the door. This was modeled by a thin box to which an image texture was mapped using a black and white picture of a hamesh. Where the image was white, the thin box was gold colored, where the texture was black, the thin box was made transparent. This is kind of cheating but it's an easy way to render a complex shape. I used this technique for several objects in the scene.

 

 

flats (31K)
Walls and floor

The walls are simply thin boxes. The brick texture for the outside wall came from the web: Absolute Background Textures Archive. A hole to fit the window was subtracted from the wall but I was lazy with the door opening because being opaque, the door hides the wall.
The inside wall has a hole for the fireplace so that the wall doesn't show inside the firebox.
The floor has a carpet texture but is barely visible through the window.

 

 

hearth (16K)
Fireplace

The fireplace is made up of boxes: the body of the fireplace, the firebox, the marble base and the mantle.

The firebox was subtracted from the main body of the fireplace. Into the cavity was placed another box: this one transparent except for the fire texture. The fire texture came from Fire/Flame Textures. The brick texture came from Absolute Background Textures Archive.

There are also a few logs sitting on some irons. These are simply cylinders.
The stockings were handled the same way as several of the other objects: a photo of a stocking applied to a thin box. The box is transparent except where the stocking is superimposed.

 

 

tree (18K)
Tree

The tree is a set of 4 slabs each with an evergreen texture (from Textures for Trees, Shrubs and Flowers) applied. The slabs were rotated a few degrees about a vertical axis through their centers so that they fanned out. From the point of view through the window and through more than one slab, the tree appears 3-dimensional.

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