Processing: Creative Coding and Computational Art

initialize x, y
x = width/2.0;
y = height/2.0;
frameRate(30);
smooth();
noStroke();
}
void draw(){
// fading background
fill(0, 5);
rect(0, 0, width, height);
fill(255);
ellipse(x, y, r*2, r*2);
}
void mouseDragged() {
x = mouseX;
y = mouseY;
}
This example works similarly to the earlier mousePressed Boolean variable example. When
you press the mouse in the display window and drag, the ellipse follows the mouse.
The next example adds a mouseMoved() function that controls a jitter and a scatter
variable, which are set as you move the mouse around the display window (without it
being pressed). The scatter variable controls the limit on a for loop, while the jitter
variable controls the radius on a ring of random ellipses created in the for loop. Upon
dragging the mouse (i.e., with the button pressed), the ring of ellipses will follow the cursor
using the last jitter and scatter settings set. This is because mouse dragging and
mouse moving, similarly to the press and release events, are processed as unique mouse
event states—you can’t press and release at the same time, nor can you move and drag at
the same time.
// mouseMoved Example
float x, y;
// declare and initialize radius
float r = 1.5;
float jitter = 5;
float scatter = 1;
void setup(){
size(400, 400);
// initialize x, y
x = width/2.0;
y = height/2.0;
frameRate(30);
smooth();
noStroke();
INTERACTIVITY
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