Transcript [Joel Goldfinger]

Distributed Ray Tracing
Robert L. Cook
Thomas Porter
Loren Carpenter
What is Distributed Ray Tracing?

Distributed Ray Tracing uses randomly
distributed oversampling to remove the
aliasing effect in the rendered image.
Distributed Ray Tracing Topics
Gloss (Blurred Reflections)
 Translucency (Blurred Transparency)
 Penumbras (Soft Shadows)
 Depth of Field
 Motion Blur

Gloss (Blurred Reflections)

Standard ray tracing produces sharp
reflections (mirror like).

Distributed ray tracing uses multiple rays
around the reflected ray to produce a blur
image of the reflected object.
Sharp VS Fuzzy Gloss
Standard Ray Tracer
Distributed Ray Tracer
( 50 Rays )
Another Gloss Example
Translucency (Blurred Transparency)

Standard ray tracing are good at
producing perfectly transparent surface.

Distributed ray tracing uses multiple rays
around the refracted ray to cause a
blurring effect.
Sharp VS Fuzzy Transparency
Standard Ray Tracer
Distributed Ray Tracer
( 20Rays )
Another Transparent Example
Penumbras (Soft Shadows)
Occurs when the light source is partially
obscured.
 With normal ray tracing a point is either
obscured or not, which cause Hard
Shadows.
 Distributed ray tracing uses many rays to
see how much of the light source is
obscured.

Hard VS Soft Shadows
Standard Ray Tracer
Distributed Ray Tracer
( 50 Rays )
Another Soft Shadow Example
Depth of Field

Regular ray tracing uses the pinhole
camera model which produces perfectly in
focus images.

Distributed ray tracing places a lens in
front of the view plane which causes
objects far from the focal plane to blur.
Depth of Field Example
Motion Blur

Occurs when an object is moving relative
to the camera.

Distributed ray tracing takes multiple ray
samples through a certain number of
frames to calculate the blur effect.
Motion Blur Example
All Techniques Combined
Conclusions

All of the methods covered under
distributed ray tracing are all interrelated.

Without the ability to antialias point
sampling Distributed ray tracing would not
have been possible.