Processing: Creative Coding and Computational Art

PROCESSING: CREATIVE CODING AND COMPUTATIONAL ART
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Figure 6-34. Scribble Plotter sketch
There’s nothing new in this sketch. However, there are a few details that might need a little
clarification. The two constant variables SCRIBBLE and HATCHING have global scope since I
declared them at the top of the program.
int SCRIBBLE = 0;
int HATCHING = 1;
I passed them in as arguments from the makeRect() function to the scribble() function.
They are capitalized, denoting that they are constants and should not be assigned a new
value. If I really wanted to enforce that they shouldn’t be changed, I could have prefaced
the declaration statements with the word final, as in final int HATCHING = 1. final is
technically a Java keyword—it’s not within the Processing API—but it can be used within
Processing. If you expand upon this sketch (which I hope you do), and want to add another
scribble-style algorithm, then create a new constant, pass it as an argument, and detect for
it in the scribble() function.
Hopefully you can make some sense of the scribble() function. I’m dividing up the x and
y distances between the starting and ending points (passed into the function), and then
plotting lines to those intermediate positions. The random() function just jitters the placement
of the line vertices. The SCRIBBLE style requires an extra line of code to ensure that
the final line connects back to the original point. Try commenting out the line() function
call within the else block inside the scribble function() conditional block.