protected void onExplosionCheckCharacterCollision(
      float x, float y, float explosionRadius, Character character, HashMap<Character, Float> map) {
    final float DISTANCE =
        Ruler.getDistance(x, y, character.getBoundaryCenterX(), character.getBoundaryCenterY());

    if (DISTANCE <= explosionRadius) map.put(character, (1f - DISTANCE / explosionRadius));
  }