6. //
float mx;
float my;
float delay = 10.0;
void setup()
{
size(400,400);
colorMode(HSB,360,100,100,100);
smooth();
fill(200,100,100,100);
noStroke();
}
void draw()
{
background(0,0,25);
ellipse(mouseX, mouseY, 40, 40);
}

9. //
float mx;
float my;
float delay = 10.0;
void setup()
{
size(400,400);
colorMode(HSB,360,100,100,100);
smooth();
noStroke();
}
void draw()
{
background(0,0,25);
float dx = mouseX - mx;
if(abs(dx) > 1) {
mx = mx + dx/delay;
}
float dy = mouseY - my;
if(abs(dy) > 1) {
my = my + dy/delay;
}
fill(200,80,80);
ellipse(mx, my, 40, 40);
}

12. //
int LENGTH = 30;
int[] x = new int[LENGTH];
int[] y = new int[LENGTH];
void setup(){
size(400,400);
colorMode(HSB,360,100,100,100);
frameRate(30);
smooth();
stroke(200,100,100);
noFill();
}
void draw(){
background(0);
for(int i=1; i<LENGTH; i++){
x[LENGTH-i] = x[LENGTH-i-1];
y[LENGTH-i] = y[LENGTH-i-1];
}
x[0] = mouseX;
y[0] = mouseY;
ellipse(x[LENGTH-1],y[LENGTH-1],40,40);
}

15. // y[LENGTH-i] = y[LENGTH-
int NUM = 12; i-1];
int DELAY = 10; }
int LENGTH = NUM*DELAY; x[0] = mouseX;
int MAX_SIZE = 600; y[0] = mouseY;
int[] x = new int[LENGTH]; for(int i=1; i<NUM; i++){
int[] y = new int[LENGTH]; ellipse(x[i*DELAY],
y[i*DELAY],
void setup(){ dSize*i,
size(400,400); dSize*i);
colorMode(HSB,360,100,100,100); }
frameRate(30); }
smooth();
stroke(200,100,100,100);
noFill();
}
void draw(){
background(0);
float dSize = MAX_SIZE / NUM;
for(int i=1; i<LENGTH; i++){
x[LENGTH-i] = x[LENGTH-
i-1];

19. //
void setup(){
size(400,400);
colorMode(HSB,360,100,100,100);
frameRate(30);
smooth();
noFill();
stroke(200,100,100);
}
void draw(){
background(0,0,25);
float x = width/2;
float y = height/2;
translate(x,y);
rotate(atan2(mouseY-y,mouseX-x));
line(-10,0,10,0);
ellipse(14,0,8,8);
}

22. // ( ) line(-5,0,5,0);
int NUM = 400; ellipse(7,0,4,4);
float[] x = new float[NUM]; popMatrix();
float[] y = new float[NUM]; }
}
//
void setup(){
size(400,400);
colorMode(HSB,360,100,100,100);
frameRate(30);
smooth();
noFill();
stroke(200,100,100);
for(int i=0; i<NUM; i++){
x[i] = random(width);
y[i] = random(height);
}
}
void draw(){
background(0);
for(int i=0; i<NUM; i++){
pushMatrix();
translate(x[i],y[i]);
rotate(atan2(mouseY-y[i],
mouseX-x[i]));

26. // pushMatrix();
translate(width/2, height/2);
rotate(angle);
float aSpeed, angle;
drawGrid();
boolean pressed;
popMatrix();
//
angle += aSpeed;
void setup(){ if(pressed){
size(400,400); aSpeed += 0.001;
colorMode(HSB,360,100,100,100); }
rectMode(CENTER); else if(aSpeed>0) {
frameRate(30); aSpeed -= 0.01;
smooth(); } else {
noFill(); aSpeed = 0;
noStroke(); }
aSpeed = 0; }
angle = 0;
pressed = false;
}
//
void draw(){
background(0,0,25);

27. //
void mousePressed(){
pressed = true;
}
//
void mouseReleased(){
pressed = false;
}
//
void drawGrid(){
fill(0,0,100);
rect(-200,-200,400,400);
rect(200,200,400,400);
fill(0,0,0);
rect(-200,200,400,400);
rect(200,-200,400,400);
}