Processing: Creative Coding and Computational Art

Figure 6-19. Yin Yang Fade sketch, variation 2
Try running this code a couple times to see how it changes. The shift from black to white,
in both the grid and razor-tooth pattern, creates an interesting example of sfumato (or
smoke), giving the image a sense of atmosphere. You’ll notice in the code that I reversed
the order of the grid and the razor-tooth pattern code blocks. Putting the grid down first
created more clarity in the final image. Try reversing the blocks of code to see the difference.
In the next examples, you’ll explore some other ways of generating lines in
Processing.
Creating lines with pixels
Besides using Processing’s point() function to generate lines, you can also directly set the
value of a line of pixels. In the next example, a PImage object is created, and the pixels
along the horizontal, vertical, and diagonal center axes are set to black (see Figure 6-20).
Please note that the PImage object is not automatically rendered to the screen; to do so,
you need to explicitly call the image() function (see the last line of code in the example).
size(500, 300);
background(255);
// used by diagonal lines
float slope = float(height)/float(width);
PImage img = createImage(width, height, RGB);
color c = color(0, 0, 0);
//horizontal line
for (int i=0; i