sketch-bezier

buggywave.pde

void draw() {
  // Clear
  fill(127);
  rect(0,250,500,25);
  // println("DEBUG: rect-clear");
  
  // Wave
  fill(0, 255, 213);
  beginShape();
  for (int i = wave-150; i<=(wave+width+50); i += 50) {
    println("DEBUG: (i % 100) == " + (i % 100));
    println("DEBUG: (wave % 100) == " + (wave % 100));
    curveVertex(i,(((i % 100) == (wave % 100)) ? 250 : 275));
  }
  endShape();
  fill(255);
  
  // Move
  wave=(wave>100) ? 0 : wave+1;
  
  // println("DEBUG: wave == " + wave);
  
  // Be stupid
  // Slow down!
  if (mousePressed){
    try {Thread.sleep(200);} catch (InterruptedException e){}
  }
}

checkbox.pde

// http://forum.processing.org/two/discussion/4849/checkbox/p1
class Checkbox {
  // Checkbox, 20-20
  int x, y;
  boolean b;
  Checkbox(int _x, int _y){
    x = _x;
    y = _y;
    b = false;
  }
  void render(){
    stroke(255);
    fill(isOver()?128:64);
    rect(x, y, 20, 20);
    if(b){
      line(x, y, x+20, y+20);
      line(x, y+20, x+20, y);
    }
  }
  void click(){
    if(isOver()){
      b=!b;
    }
  }
  boolean isOver(){
    return(mouseX>x&&mouseX<x+20&&mouseY>y&&mouseY<y+20);
  }
}

Checkbox foo = new Checkbox(40,10);
void setup(){
  background(127);
  smooth();
}

void draw(){
  // This is a hello world
  
  foo.render();
  if (mousePressed){
    foo.click();
  }
}

gistfile1.pde

// Inaccurate clone of http://www.w3schools.com/svg/svg_path.asp
size(450,400);
background(255);
fill(0);
ellipse(100,350,2,2);
ellipse(250,50,2,2);
ellipse(400,350,2,2);
stroke(255,0,0);line(100,350,250,50);line(250,50,400,350);
// stroke(0,255,0);line(175,200,325,200);
noFill();
stroke(0,0,255);
beginShape();
vertex(100,350);
bezierVertex(100,350,250,50,400,350);
endShape();

gistfile2.pde

// Clone of https://www.khanacademy.org/cs/animated-waves/4601853285236736

int wave = 0;
void setup(){
  size(500,500);
  background(127);
  noStroke();
}
void draw() {
  // Clear
  fill(127);
  rect(0,250,500,25);
  // println("DEBUG: rect-clear");
  
  // Wave
  fill(0, 255, 213);
  beginShape();
  curveVertex(wave-150,250);
  curveVertex(wave-100,275);
  curveVertex(wave-50,250);
  curveVertex(wave+0,275);
  curveVertex(wave+50,250);
  curveVertex(wave+100,275);
  curveVertex(wave+150,250);
  curveVertex(wave+200,275);
  curveVertex(wave+250,250);
  curveVertex(wave+300,275);
  curveVertex(wave+350,250);
  curveVertex(wave+400,275);
  curveVertex(wave+450,250);
  curveVertex(wave+500,275);
  curveVertex(wave+550,250);
  endShape();
  fill(255);
  
  // Move
  wave=(wave>100) ? 0 : wave+1;
  
  // println("DEBUG: wave == " + wave);
  
  // Be stupid
  // Slow down!
  if (mousePressed){
    try {Thread.sleep(50);} catch (InterruptedException e){}
  }
}