Processing: Creative Coding and Computational Art

PROCESSING: CREATIVE CODING AND COMPUTATIONAL ART
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Figure 10-31. Tint sketch (using bitwise operations)
Again, let me stress the fact that you do not need to use bitwise operations in Processing.
The Processing functions red(c), green(c), blue(c), and alpha(c) also return the individual
color component values. However, once you get past the strange bitwise syntax
(i.e., >> 16 & 0xFF), you’ll realize they are relatively easy to use, and again, fast.
The last sketch utilized two PImages; the first was created with the line
PImage img = loadImage("changsha2.jpg");
which is the syntax I looked at earlier to create a PImage based on a loaded image. The second
PImage was created with the following line:
PImage img2 = createImage(img.width, img.height, RGB);
This is the syntax to use when you want to create a PImage, but initially only specify its size
and color format. Notice that I specified the size of the second PImage using the width and
height properties of the first PImage, ensuring that both images were the same size.
As you may remember, every PImage includes a pixels[] array that contains all the color
values in the image. Once I created the second PImage, I copied the pixels[] array from
the first PImage into the second using Processing’s arrayCopy(src, dest) function.
This is a pretty handy function that you need to use to copy arrays. You can’t simply copy
an array using syntax like array1 = array2, which only works for primitive types, such as
int1 = int2. Arrays and objects are reference types. You may remember from earlier in