Code
ArrayList<star> stars = new ArrayList<star>();
ArrayList<particle> particles = new ArrayList<particle>();
float globalG = 0.1, colorOffset = 50, minStarSpeed = 2, maxStarSpeed = 6, minParticleSpeed = 2, maxParticleSpeed = 3, starSize = 8;
void setup() {
fullScreen();
//size(600,600);
colorMode(HSB);
}
void draw() {
background(0);
for(int i = 0; i < stars.size(); i++) {
stars.get(i).move();
stars.get(i).display();
//checking for stars to delete
if(stars.get(i).x > width*1.5 || stars.get(i).y > height*1.5) {
stars.remove(i);
}
}
for(int i = 0; i < particles.size(); i++) {
particles.get(i).move();
particles.get(i).display();
//deleting particels
if(particles.get(i).age > particles.get(i).maxAge) {
particles.remove(i);
}
}
if(random(100) > 90) {
addStar(random(width/2),random(height/2),random(minStarSpeed,maxStarSpeed),random(minStarSpeed,maxStarSpeed),color(random(255),255,255));
}
}
void mousePressed() {
addStar(mouseX,mouseY,5,5,color(random(255),255,255));
}
void addStar(float x, float y, float xs, float ys, color clrFill) {
stars.add(new star(x,y,xs,ys,clrFill));
}
class star {
float xs,ys, x,y, r = starSize;
color clr;
star(float x_, float y_, float xs_, float ys_, color clr_) {
x = x_;
y = y_;
xs = xs_;
ys = ys_;
clr = clr_;
}
void display() {
fill(clr);
noStroke();
circle(x,y,r*2);
}
void move() {
x += xs;
y += ys;
float rep = random(2,10);
for(int i = 0; i < rep; i++) {
float dir = random(TWO_PI), speed = random(minParticleSpeed,maxParticleSpeed);
addParticle(x,y,cos(dir)*speed,sin(dir)*speed,0,20, color(hue(clr)+random(-colorOffset/2, colorOffset/2),255,255));
}
}
}
class particle {
float x,y,xs,ys,age,maxAge;
int id;
color clr;
particle(float x_, float y_, float xs_, float ys_, int startAge_, int maxAge_, color clrFill) {
x = x_;
y = y_;
xs = xs_;
ys = ys_;
age = startAge_;
maxAge = maxAge_;
clr = clrFill;
}
void display() {
fill(clr, map( age,0,maxAge,255,0));
noStroke();
circle(x,y,5);
}
void move() {
ys+=globalG;
x += xs;
y += ys;
age++;
}
}
void addParticle(float x, float y, float xs, float ys, int startAge, int maxAge, color clrFill) {
particles.add(new particle(x,y,xs,ys,startAge,maxAge, clrFill));
}
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