Processing: Creative Coding and Computational Art

As you might suspect, anti-aliasing techniques can dramatically impact performance, as
the anti-aliasing calculations take time. Processing therefore has two functions: smooth()
and noSmooth(). The first turns anti-aliasing on and the second turns it off. Anti-aliasing is
off by default in Processing. This simple example illustrates the visual difference between
aliasing and anti-aliasing in Processing; the ellipse on the left of Figure 6-33, using the
default rendering state, is aliased, and the ellipse on the right is anti-aliased using
Processing’s smooth() function.
size(430, 220);
strokeWeight(2);
ellipseMode(CORNER);
//aliased
ellipse(10, 10, 200, 200);
smooth();
//anti-aliased
ellipse(220, 10, 200, 200);
Figure 6-33. Anti-aliasing example
Please note that calling smooth() can slightly reduce the stroke weight of fine lines. This
can become a factor when you specify small stroke weights. Type in Processing utilizes its
own anti-aliasing procedure, so calling smooth() will have no impact on the type’s edges.
To specify anti-aliasing with type, you need to either specify the smooth parameter when
calling the createFont() function, or go to Tools ➤ Create Font and select the Smooth
option. Type is always anti-aliased in OS X.
Returning to the Point Recorder/Plotter sketch, I want to give one further example illustrating
another cool feature of using this record/plot approach. Since the point data is
recorded in the xy[][] array and then plotted to the screen, I can manipulate or utilize
the point information in the middle of the plotting. The best way to handle this is to create
another simple function that I can pass the point data to for further processing. You can
think of this process like an assembly line, where, for example, a mechanical arm moves a
component down the line, while other machines paint, weld, and bend it. In the next
example, as the points are processed in the makeRect() function, they get sent to the
scribble() function, which creates scribbly lines between the points. See Figure 6-34 for
the screen output of this example.
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