Graphics Reference
In-Depth Information
yourself with glue and rolled around in a deep pile of multi-colored confetti.
When you stood up, confetti would stick to you everywhere. Your body's sur-
face would be snugly encased inside a dense, colorful shell of tiny paper dots.
Now imagine that someone watching this spectacle had the patience to
meticulously record the precise location of every sticky, individual piece of
confetti on your body's surface. Maybe on his irst attempt, your scribe would
patiently record each confetti's location descriptively, for example, as “one red
confetti on tip of nose.” After laboriously writing it out this way, your scribe
would realize a more eficient way to capture the details of your confetti-
covered self in all its colorful glory: to jot down the individual location of
each tiny piece of paper according to its precise location in space, or by its x,
y, and z coordinates.
That's essentially how scanners capture physical dimensions of things, as
a surface coating of digital confetti. Each piece of digital confetti represents a
data point. Each data point contains information about where each tiny dot
sits on your body's surface in three-dimensional space, documented as a set
of x, y, and z coordinates.
Another name for the digital confetti that coats our surfaces is a “point
cloud.” Most scanners capture a point cloud digitally and feed that data to a
computer. After scan data is uploaded into design software, to make sense of
its collection of location coordinates, the design software performs a series of
rapid calculations to convert the point cloud into a surface mesh, sometimes
calculating missing data points to ill in a surface gap.
3D printing and point clouds are a match made in heaven. Scan data opens
up a new universe of design possibilities and unleashes the true disruptive
potential of 3D printing. Scanning is useful for capturing the geometry of
objects for which no design ile exists, for example, natural objects such as
plants, animals, and people, anatomical models, as well as of inanimate objects
like rocks and even landscapes. Scanning is also useful for capturing the shape
of synthetic objects when the original CAD ile is unavailable or never existed,
such as archeological objects and broken parts.
Scan data is, in my opinion, the bridge that's going to span the gulf between
the analog physical world and the binary digital world. Scanned and repro-
duced physical objects are where the line begins to blur between original and
replica, between copyrighted object and derivative work. Scanned data, once
captured in a design ile, can be edited, replicated, and copied. Someday we
will edit the physical world as easily as we edit digital photographs.
