Processing: Creative Coding and Computational Art

PROCESSING: CREATIVE CODING AND COMPUTATIONAL ART
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Figure 4-11. Repeating distorted sine curve
When patterns overlap and interfere with each other, interesting things happen, such as
moiré patterns. In printing, moiré patterns are usually an unwanted phenomenon, occurring
from interfering line screen frequencies. However, these patterns can also be quite
beautiful, causing interesting visual distortions and secondary patterns to emerge. In the
following example sketch (shown in Figure 4-12), the wave pattern continuously redraws
itself, with some of the waveform properties controlled by the position of the mouse during
runtime. In addition, a second concentric ring pattern moves around with the cursor,
causing some interesting distortions to occur. You can also press the mouse and hold it,
and the ring pattern will grow; when you let go, it will shrink back to its original size.
/* Interference and moiré pattern
Ira Greenberg, October 18, 2005 */
float interval;
float spacer;
// Experiment with these values
float angle = 0;
float amplitude = .05;