Processing: Creative Coding and Computational Art

PROCESSING: CREATIVE CODING AND COMPUTATIONAL ART
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Java mode
This mode allows you to work in pure Java, from directly within the Processing text editor.
Java mode is extremely flexible, giving you access to the entire Java API. However, this
mode is for advanced users who already have a working knowledge of Java. I’ll discuss
Java mode in more detail in Chapter 14.
Rendering modes
Processing, as of this writing, has three rendering modes: JAVA2D, P3D, and OPENGL. The
mode can be explicitly set as an optional argument within Processing’s size() method. For
example, to use the P3D rendering mode, you would write: size(200, 200, P3D);. The
rendering modes control how visual data is rendered, or converted to pixels on the screen.
In addition to these three modes, there is a fourth mode, called P2D, that will likely be
functional in the near future (it very well may be active by the time you’re reading this).
P2D is an alternative renderer (obviously for 2D rendering) to JAVA2D.
JAVA2D mode
JAVA2D uses Java’s 2D graphics library for creating 2D rendering. According to Sun, Java 2D
is “a set of classes for advanced 2D graphics and imaging.” The library contains over 100
classes organized into packages according to related functionality (e.g., imaging, drawing,
and color). JAVA2D is the default rendering mode in Processing. Thus, when no rendering
argument is explicitly specified within the size() function, JAVA2D is used. Coders normally
don’t bother adding the JAVA2D argument to the size() call for this reason.
Here is a JAVA2D example that generates a polygon, in this case an octagon. You can
change the value of the sides variable to generate other types of polygons. All the examples
in the book thus far have been in JAVA2D mode. Figure 5-12 shows the output of the
example.
/*
Polygon
Ira Greenberg, November 3, 2005
*/
// declare variables
int sides = 8; // change to create other polys
float angle;
float radius = 100;
float px, py, cx, cy;
float[]ptsX= new float[sides];
float[]ptsY= new float[sides];
//initialize sketch
void setup(){
size(200, 200, JAVA2D);