In my previous blog post, I was talking about how I failed to extend the Rectangle class, and had to step back and learn a few more basics. Now approximately 8 hours later, a lot of pages, videos and other things (completely unrelated to Java), I’ve managed to get it working.

For me this a huge step in the right direction, and when the penny finally hit, it didn’t take more than a few minutes to actually change the code to reflect what I wanted to do.

Again, the original spawnRaindrop() code:

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private void spawnRaindrop() {
    Rectangle raindrop = new Rectangle();
    raindrop.x = MathUtils.random(0, 800-48);
    raindrop.y = 480;
    raindrop.width = 48;
    raindrop.height = 48;
    raindrops.add(raindrop)
    lastDropTime = TimeUtils.nanoTime();
}
private void spawnRaindrop() {
	Rectangle raindrop = new Rectangle();
	raindrop.x = MathUtils.random(0, 800-48);
	raindrop.y = 480;
	raindrop.width = 48;
	raindrop.height = 48;
	raindrops.add(raindrop)
	lastDropTime = TimeUtils.nanoTime();
}

 

And the modified version

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private void spawnRaindrop() {
    Raindrop raindrop = new Raindrop();
    raindrop.x = MathUtils.random(0, 800-48);
    raindrop.y = 480;
    raindrop.width = 48;
    raindrop.height = 48;
    raindrop.speed = MathUtils.random(50,200);
    raindrops.add(raindrop);
    lastDropTime = TimeUtils.nanoTime();
}
private void spawnRaindrop() {
	Raindrop raindrop = new Raindrop();
	raindrop.x = MathUtils.random(0, 800-48);
	raindrop.y = 480;
	raindrop.width = 48;
	raindrop.height = 48;
	raindrop.speed = MathUtils.random(50,200);
	raindrops.add(raindrop);
	lastDropTime = TimeUtils.nanoTime();
}

 

The Raindrop class

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package com.badlogic.drop;
 
import com.badlogic.gdx.math.Rectangle;
 
public class Raindrop extends Rectangle {
    float speed;
 
    public Raindrop() {
        super();
    }
 
    public Raindrop(float x, float y, float width, float height, float speed) {
        super(x, y, width, height);
        this.speed = speed;
    }
}
package com.badlogic.drop;

import com.badlogic.gdx.math.Rectangle;

public class Raindrop extends Rectangle {
	float speed;

	public Raindrop() {
		super();
	}

	public Raindrop(float x, float y, float width, float height, float speed) {
		super(x, y, width, height);
		this.speed = speed;
	}
}

 

And the entire Drop.java code with the new shiny Raindrop class in action (I took the liberty of copying directly from the tutorial page since I had mangled the original code somewhat awful)

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package com.badlogic.drop;
 
import java.util.Iterator;
 
import com.badlogic.gdx.ApplicationListener;
import com.badlogic.gdx.Gdx;
import com.badlogic.gdx.Input.Keys;
import com.badlogic.gdx.audio.Music;
import com.badlogic.gdx.audio.Sound;
import com.badlogic.gdx.graphics.GL10;
import com.badlogic.gdx.graphics.OrthographicCamera;
import com.badlogic.gdx.graphics.Texture;
import com.badlogic.gdx.graphics.g2d.SpriteBatch;
import com.badlogic.gdx.math.MathUtils;
import com.badlogic.gdx.math.Rectangle;
import com.badlogic.gdx.math.Vector3;
import com.badlogic.gdx.utils.Array;
import com.badlogic.gdx.utils.TimeUtils;
 
public class Drop implements ApplicationListener {
   Texture dropImage;
   Texture bucketImage;
   Sound dropSound;
   Music rainMusic;
   SpriteBatch batch;
   OrthographicCamera camera;
   Rectangle bucket;
   Array<Raindrop> raindrops;
   long lastDropTime;
 
   @Override
   public void create() {
      // load the images for the droplet and the bucket, 48x48 pixels each
      dropImage = new Texture(Gdx.files.internal("droplet.png"));
      bucketImage = new Texture(Gdx.files.internal("bucket.png"));
 
      // load the drop sound effect and the rain background "music"
      dropSound = Gdx.audio.newSound(Gdx.files.internal("drop.wav"));
      rainMusic = Gdx.audio.newMusic(Gdx.files.internal("rain.mp3"));
 
      // start the playback of the background music immediately
      rainMusic.setLooping(true);
      rainMusic.play();
 
      // create the camera and the SpriteBatch
      camera = new OrthographicCamera();
      camera.setToOrtho(false, 800, 480);
      batch = new SpriteBatch();
 
      // create a Rectangle to logically represent the bucket
      bucket = new Rectangle();
      bucket.x = 800 / 2 - 48 / 2; // center the bucket horizontally
      bucket.y = 20; // bottom left corner of the bucket is 20 pixels above the bottom screen edge
      bucket.width = 48;
      bucket.height = 48;
 
      // create the raindrops array and spawn the first raindrop
      raindrops = new Array<Raindrop>();
      spawnRaindrop();
   }
 
   private void spawnRaindrop() {
      Raindrop raindrop = new Raindrop();
      raindrop.x = MathUtils.random(0, 800-48);
      raindrop.y = 480;
      raindrop.width = 48;
      raindrop.height = 48;
      raindrop.speed = MathUtils.random(0,50);
      raindrops.add(raindrop);
      lastDropTime = TimeUtils.nanoTime();
   }
 
   @Override
   public void render() {
      // clear the screen with a dark blue color. The
      // arguments to glClearColor are the red, green
      // blue and alpha component in the range [0,1]
      // of the color to be used to clear the screen.
      Gdx.gl.glClearColor(0, 0, 0.2f, 1);
      Gdx.gl.glClear(GL10.GL_COLOR_BUFFER_BIT);
 
      // tell the camera to update its matrices.
      camera.update();
 
      // tell the SpriteBatch to render in the
      // coordinate system specified by the camera.
      batch.setProjectionMatrix(camera.combined);
 
      // begin a new batch and draw the bucket and
      // all drops
      batch.begin();
      batch.draw(bucketImage, bucket.x, bucket.y);
      for(Rectangle raindrop: raindrops) {
         batch.draw(dropImage, raindrop.x, raindrop.y);
      }
      batch.end();
 
      // process user input
      if(Gdx.input.isTouched()) {
         Vector3 touchPos = new Vector3();
         touchPos.set(Gdx.input.getX(), Gdx.input.getY(), 0);
         camera.unproject(touchPos);
         bucket.x = touchPos.x - 48 / 2;
      }
      if(Gdx.input.isKeyPressed(Keys.LEFT)) bucket.x -= 200 * Gdx.graphics.getDeltaTime();
      if(Gdx.input.isKeyPressed(Keys.RIGHT)) bucket.x += 200 * Gdx.graphics.getDeltaTime();
 
      // make sure the bucket stays within the screen bounds
      if(bucket.x < 0) bucket.x = 0;
      if(bucket.x > 800 - 48) bucket.x = 800 - 48;
 
      // check if we need to create a new raindrop
      if(TimeUtils.nanoTime() - lastDropTime > 1000000000) spawnRaindrop();
 
      // move the raindrops, remove any that are beneath the bottom edge of
      // the screen or that hit the bucket. In the later case we play back
      // a sound effect as well.
      Iterator<Raindrop> iter = raindrops.iterator();
      while(iter.hasNext()) {
         Raindrop raindrop = iter.next();
         raindrop.y -= raindrop.speed * Gdx.graphics.getDeltaTime();
         if(raindrop.y + 48 < 0) iter.remove();
         if(raindrop.overlaps(bucket)) {
            dropSound.play();
            iter.remove();
         }
      }
   }
 
   @Override
   public void dispose() {
      // dispose of all the native resources
      dropImage.dispose();
      bucketImage.dispose();
      dropSound.dispose();
      rainMusic.dispose();
      batch.dispose();
   }
 
   @Override
   public void resize(int width, int height) {
   }
 
   @Override
   public void pause() {
   }
 
   @Override
   public void resume() {
   }
}
package com.badlogic.drop;

import java.util.Iterator;

import com.badlogic.gdx.ApplicationListener;
import com.badlogic.gdx.Gdx;
import com.badlogic.gdx.Input.Keys;
import com.badlogic.gdx.audio.Music;
import com.badlogic.gdx.audio.Sound;
import com.badlogic.gdx.graphics.GL10;
import com.badlogic.gdx.graphics.OrthographicCamera;
import com.badlogic.gdx.graphics.Texture;
import com.badlogic.gdx.graphics.g2d.SpriteBatch;
import com.badlogic.gdx.math.MathUtils;
import com.badlogic.gdx.math.Rectangle;
import com.badlogic.gdx.math.Vector3;
import com.badlogic.gdx.utils.Array;
import com.badlogic.gdx.utils.TimeUtils;

public class Drop implements ApplicationListener {
   Texture dropImage;
   Texture bucketImage;
   Sound dropSound;
   Music rainMusic;
   SpriteBatch batch;
   OrthographicCamera camera;
   Rectangle bucket;
   Array<Raindrop> raindrops;
   long lastDropTime;

   @Override
   public void create() {
      // load the images for the droplet and the bucket, 48x48 pixels each
      dropImage = new Texture(Gdx.files.internal("droplet.png"));
      bucketImage = new Texture(Gdx.files.internal("bucket.png"));

      // load the drop sound effect and the rain background "music"
      dropSound = Gdx.audio.newSound(Gdx.files.internal("drop.wav"));
      rainMusic = Gdx.audio.newMusic(Gdx.files.internal("rain.mp3"));

      // start the playback of the background music immediately
      rainMusic.setLooping(true);
      rainMusic.play();

      // create the camera and the SpriteBatch
      camera = new OrthographicCamera();
      camera.setToOrtho(false, 800, 480);
      batch = new SpriteBatch();

      // create a Rectangle to logically represent the bucket
      bucket = new Rectangle();
      bucket.x = 800 / 2 - 48 / 2; // center the bucket horizontally
      bucket.y = 20; // bottom left corner of the bucket is 20 pixels above the bottom screen edge
      bucket.width = 48;
      bucket.height = 48;

      // create the raindrops array and spawn the first raindrop
      raindrops = new Array<Raindrop>();
      spawnRaindrop();
   }

   private void spawnRaindrop() {
      Raindrop raindrop = new Raindrop();
      raindrop.x = MathUtils.random(0, 800-48);
      raindrop.y = 480;
      raindrop.width = 48;
      raindrop.height = 48;
      raindrop.speed = MathUtils.random(0,50);
      raindrops.add(raindrop);
      lastDropTime = TimeUtils.nanoTime();
   }

   @Override
   public void render() {
      // clear the screen with a dark blue color. The
      // arguments to glClearColor are the red, green
      // blue and alpha component in the range [0,1]
      // of the color to be used to clear the screen.
      Gdx.gl.glClearColor(0, 0, 0.2f, 1);
      Gdx.gl.glClear(GL10.GL_COLOR_BUFFER_BIT);

      // tell the camera to update its matrices.
      camera.update();

      // tell the SpriteBatch to render in the
      // coordinate system specified by the camera.
      batch.setProjectionMatrix(camera.combined);

      // begin a new batch and draw the bucket and
      // all drops
      batch.begin();
      batch.draw(bucketImage, bucket.x, bucket.y);
      for(Rectangle raindrop: raindrops) {
         batch.draw(dropImage, raindrop.x, raindrop.y);
      }
      batch.end();

      // process user input
      if(Gdx.input.isTouched()) {
         Vector3 touchPos = new Vector3();
         touchPos.set(Gdx.input.getX(), Gdx.input.getY(), 0);
         camera.unproject(touchPos);
         bucket.x = touchPos.x - 48 / 2;
      }
      if(Gdx.input.isKeyPressed(Keys.LEFT)) bucket.x -= 200 * Gdx.graphics.getDeltaTime();
      if(Gdx.input.isKeyPressed(Keys.RIGHT)) bucket.x += 200 * Gdx.graphics.getDeltaTime();

      // make sure the bucket stays within the screen bounds
      if(bucket.x < 0) bucket.x = 0;
      if(bucket.x > 800 - 48) bucket.x = 800 - 48;

      // check if we need to create a new raindrop
      if(TimeUtils.nanoTime() - lastDropTime > 1000000000) spawnRaindrop();

      // move the raindrops, remove any that are beneath the bottom edge of
      // the screen or that hit the bucket. In the later case we play back
      // a sound effect as well.
      Iterator<Raindrop> iter = raindrops.iterator();
      while(iter.hasNext()) {
         Raindrop raindrop = iter.next();
         raindrop.y -= raindrop.speed * Gdx.graphics.getDeltaTime();
         if(raindrop.y + 48 < 0) iter.remove();
         if(raindrop.overlaps(bucket)) {
            dropSound.play();
            iter.remove();
         }
      }
   }

   @Override
   public void dispose() {
      // dispose of all the native resources
      dropImage.dispose();
      bucketImage.dispose();
      dropSound.dispose();
      rainMusic.dispose();
      batch.dispose();
   }

   @Override
   public void resize(int width, int height) {
   }

   @Override
   public void pause() {
   }

   @Override
   public void resume() {
   }
}

I hope this is helpful to someone else, if not at least I have some place to find this when I wake up and have forgotten all about it.

Drop 1
Me 1

Your move Java!

On another note, I really need to add a couple of things to this wordpress blog. Color coded syntax and an easier way to add the code would be a start. Also I’ve been asked to add some syndication for the entire site, so I’ll look into that sometime soon as well.