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Flash
is a vector-based animation format by
Macromedia which is very popular on
today's Web. Its vector capabilities allow
it to store resolution-independent, scalable
graphics in a very efficient manner.
Although it can embed bitmaps, most Flash
graphics on the Web is built around vector
objects whose shape and motion parameters
are defined numerically. Although there
exist sites that are built with Flash from
ground up (such as the olympic.org
already mentioned), more frequently Flash
movies are used in more limited roles, such
as an intro on a site's opening page. To
view a Flash animation, you need to install
a free plug-in from Macromedia, although
newer versions of Microsoft's and Netscape's
browsers come with that plug-in
pre-installed.
The Flash
format, besides its practical merits, is
very instructive in how its mathematical
inventory can nevertheless be used to create
movies with a surprisingly live and casual
feel. You may already have an idea of how
difficult it is, when using a vector drawing
program, to give your graphic the softness
and finish characteristic of professional
bitmap graphics. In "live" animated
graphics, inherent vector rigidity tends to
look even more disgusting. However, although
Flash's editing tools are only a subset of
those found in major vector drawing
programs, it is still capable of
implementing all of the delinearization
techniques discussed
above,such as acceleration or deceleration, color
and transparency control, etc.
At the most basic level, this
graduality is controlled by the "blow up"
effect of the title element being magnified.
Then, its rotation makes it more difficult
to grasp the message of the text and ensures
that it is being read exactly in the order
prescribed by the designer. Both rotation
and size increase are nonlinear; note how it
temporarily slows down when each of the two
crossed lines approach horizontality. The
final stage, where the central dot explodes
into a white screen, emphasizes this
nonlinearity by transforming the
rotating
object into something essentially new -
which is especially pertinent at the end of
the movie, when its main message has already
been delivered and the viewers are therefore
most likely to divert their attention.
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