Add bonus particle system class

core/src/io/github/lonamiwebs/klooni/game/BonusParticle.java

@@ -0,0 +1,39 @@
+package io.github.lonamiwebs.klooni.game;
+
+import com.badlogic.gdx.Gdx;
+import com.badlogic.gdx.graphics.g2d.Batch;
+import com.badlogic.gdx.math.Interpolation;
+import com.badlogic.gdx.math.Vector2;
+import com.badlogic.gdx.scenes.scene2d.ui.Label;
+
+import io.github.lonamiwebs.klooni.Klooni;
+
+class BonusParticle {
+
+    private Label label;
+    private float lifetime;
+
+    private final static float SPEED = 1f;
+
+    BonusParticle(final Vector2 pos, final int score, final Label.LabelStyle style) {
+        label = new Label("+"+score, style);
+        label.setBounds(pos.x, pos.y, 0, 0);
+    }
+
+    void run(final Batch batch) {
+        // Update
+        lifetime += SPEED * Gdx.graphics.getDeltaTime();
+        if (lifetime > 1f)
+            lifetime = 1f;
+
+        // Render
+        label.setColor(Klooni.theme.highScore);
+        label.setFontScale(Interpolation.elasticOut.apply(0f, 1f, lifetime));
+        float opacity = Interpolation.linear.apply(1f, 0f, lifetime);
+        label.draw(batch, opacity);
+    }
+
+    boolean done() {
+        return lifetime >= 1f;
+    }
+}

core/src/io/github/lonamiwebs/klooni/game/BonusParticleHandler.java

@@ -0,0 +1,34 @@
+package io.github.lonamiwebs.klooni.game;
+
+import com.badlogic.gdx.graphics.g2d.Batch;
+import com.badlogic.gdx.math.Vector2;
+import com.badlogic.gdx.scenes.scene2d.ui.Label;
+import com.badlogic.gdx.utils.Array;
+
+import java.util.Iterator;
+
+class BonusParticleHandler {
+
+    private final Array<BonusParticle> particles;
+    private final Label.LabelStyle labelStyle;
+
+    BonusParticleHandler(final Label.LabelStyle style) {
+        labelStyle = style;
+        particles = new Array<BonusParticle>();
+    }
+
+    void addBonus(final Vector2 pos, final int score) {
+        particles.add(new BonusParticle(pos, score, labelStyle));
+    }
+
+    void run(final Batch batch) {
+        BonusParticle particle;
+        Iterator<BonusParticle> iterator = particles.iterator();
+        while (iterator.hasNext()) {
+            particle = iterator.next();
+            particle.run(batch);
+            if (particle.done())
+                iterator.remove();
+        }
+    }
+}