How do I create a 4 frame destructible wall sequence?

Processing Coding Questions
1

I’m making a 2d game, and some of the walls are destructible.

There are 5 sprites for that type of wall.

  1. Normal wall sprite
  2. Destroyed frame 1
  3. Destroyed frame 2
  4. Destroyed frame 3
  5. Destroyed frame 4

All 5 of these sprites are loaded into a PImage array in setup.

The draw method in my wall class is like this: image(sprites[currentFrame], x, y)

I have a collided flag that is set to true once the player projectile hits it.

What I want it to do is once hit, trigger a 4 frame destruction sequence, where each of the destruction sprites are shown for only one frame

2 Likes
2

I can give you a system I usually implement when working with sprites:

MainSketch.pde

SpriteHandler standardHandler=new SpriteHandler();
void setup(){}
void draw(){
   standardHandler.run();
}

SpriteHandler

class SpriteHandler {
  ArrayList<Sprite> sprites=new ArrayList<Sprite>();
  SpriteHandler(){
  }
  void register(Sprite s){
    sprites.add(s);
  }
  void run(){
    for(Sprite s:sprites) s.run(s.currframe++);
    for(int i=sprites.size()-1;i>=0;i--) if(sprites.get(i).done()) sprites.remove(i);
  }
}

Sprite.pde

abstract class Sprite{
  int duration=0;
  int currframe=0;
  boolean forceQuit=false;
  boolean done(){
    return duration<=(currframe&&duration>0)||forceQuit;
  }
  void register(){
     standardHandler.register(this);
  }
  abstract void run(int frame);
}

You can make your class extend the Sprite class and implement the run method to draw your sprite.
You just have to set super.duration=4 to signal that your sprite has 4 frames.
Now once you have a collision trigger you can create a new instance of your Sprite and
call the register method on it.
If you want I could send some shorter code that is more inefficent though.

2 Likes
3

Could you please send me some shorter code? I just wanna get it working before implementing the longer method you provided

4

Good starting point!

if(collided){
   image(sprites[currentFrame], x, y);
   currentFrame++;
   if(currentFrame>4) currentFrame=4;
}else{
   image(wall,x,y);
}
1 Like
5

This would be a much shorter class that plays the sprite once the Constructor is called

final PApplet enclosing_instance=this;

public class ImageSprite {
  int x, y;
  ImageSprite(int x, int y) {
    this.x=x;
    this.y=y;
    register();
  }

  int currentFrame=0;
  int duration=4;
  void register() {
    enclosing_instance.registerMethod("draw", this);
  }
  public void draw() {
    if (currentFrame<duration) run(currentFrame);
    else enclosing_instance.unregisterMethod("draw", this);
    currentFrame++;
  }
  void run(int frame) {
    //paint your image here
    rect(x, y, 10, 10);
  }
}
1 Like