Processing: Creative Coding and Computational Art

PROCESSING: CREATIVE CODING AND COMPUTATIONAL ART
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Figure 6-4. Emerging line sketch
This is beginning to look like a real program, and it also has an insistent line. There is
something simple and beautiful about the sharpness and delicateness of the white points
against the black. You’ll notice that I called stroke(255), which sets the stroke state of
the sketch to white. I use the term “stroke state” because any drawing executed after the
stroke(255) call that involves rendering a stroke will be white, until I explicitly make
another call to change the rendering state of the stroke color—for example,
stroke(127);. I discuss the idea of a rendering state in the color section of the language
reference, found in Appendix A. The sketch is now 12 lines (of code) long and beginning
to get a little unwieldy, especially for making global changes to the program. For example,
if you want to now add a tenth point and still keep the line centered in the display window,
it’s time-consuming (and annoying) to have to go and change the value for each
point. There are two ways to simplify this process. The first is to base your point positions
on the size and shape of the display window, and the second is to add a looping structure
that will handle the iteration for you.
Here’s a solution for using ten points, implementing the first improvement:
size(300, 300);
background(0);
stroke(255);
point((width/11)*1, height/2);
point((width/11)*2, height/2);
point((width/11)*3, height/2);
point((width/11)*4, height/2);
point((width/11)*5, height/2);
point((width/11)*6, height/2);
point((width/11)*7, height/2);
point((width/11)*8, height/2);
point((width/11)*9, height/2);
point((width/11)*10, height/2);
This solution is procedurally an improvement—it uses the computer to handle the calculation
of the division by 11. Next, I’ll show you how to implement a while loop.