title: SpriteKit PhysicsBody: Could not create physics body
body: <p>I have a player in my game, it has two states flying, falling. Each of them has an image: player_flying, player_falling correspondingly. I am also using a physical bodies to detect collision. It is completely normally functioning when I use one texture. But when I am trying to use both in different conditions using different textures, it shows me an error in the log. I am trying it like that:</p>
  
  <pre><code>if (self.player.physicsBody.velocity.dy &gt; 30) {
      self.player.texture = [SKTexture textureWithImageNamed:@"player_flying"];
      self.player.physicsBody = [SKPhysicsBody bodyWithTexture:self.player.texture
                                                          size:self.player.size];        
  }
  else
  {
      self.player.texture = [SKTexture textureWithImageNamed:@"player_falling"];
      self.player.physicsBody = [SKPhysicsBody bodyWithTexture:self.player.texture
                                                          size:self.player.size];
  }
  </code></pre>
  
  <p>the error is:</p>
  
  <blockquote>
    <p>2014-08-30 12:55:47.515 kalabaska[1569:50535] PhysicsBody: Could not create physics body.</p>
  </blockquote>