processing4/java/examples/Topics/Drawing/Animator/applet/Animator.java

import processing.core.*; 

import java.applet.*; 
import java.awt.*; 
import java.awt.image.*; 
import java.awt.event.*; 
import java.io.*; 
import java.net.*; 
import java.text.*; 
import java.util.*; 
import java.util.zip.*; 
import java.util.regex.*; 

public class Animator extends PApplet {

/**
 * Animator.
 * 
 * Click and drag to draw and start the program.
 * 
 * A simple animation tool that displays a continuous cycle of
 * twenty-four images. Each image is displayed for 30 milliseconds 
 * to create animation. While each image is displayed, it\u2019s possible 
 * to draw directly into it by pressing the mouse and moving the cursor. 
 * 
 */

int currentFrame = 0;
PImage[] frames = new PImage[24];
int lastTime = 0;

public void setup() 
{
  size(640, 200);
  strokeWeight(12);
  smooth();
  background(204);
  for (int i = 0; i < frames.length; i++) {
    frames[i] = get(); // Create a blank frame
  }
}

public void draw() 
{
  int currentTime = millis();
  if (currentTime > lastTime+30) {
    nextFrame();
    lastTime = currentTime;
  }
  if (mousePressed == true) {
    line(pmouseX, pmouseY, mouseX, mouseY);
  }
}

public void nextFrame() 
{
  frames[currentFrame] = get(); // Get the display window
  currentFrame++; // Increment to next frame
  if (currentFrame >= frames.length) {
    currentFrame = 0;
  }
  image(frames[currentFrame], 0, 0);
}


  static public void main(String args[]) {
    PApplet.main(new String[] { "Animator" });
  }
}