title: box2d Apply force in a particular direction
body: <p>I want to apply a force to my object in the direction that it is currently facing, here is my code so far but it is throwing errors when I try do <code>force * t</code>, what am I doing wrong?</p>
  
  <pre><code>        b2Transform t;
          t.Set(b2Vec2(0, 0), spaceCraft-&gt;GetAngle());
          b2Vec2 force = b2Vec2(0, 2.5f);
          spaceCraft-&gt;ApplyForce(force * t, spaceCraft-&gt;GetPosition());
  </code></pre>