title: GLSL variable not passing from vertex to fragment shader
body: <p>I'm getting a strange error when trying to pass a float from my vertex to the fragment shader. </p>
  
  <p>Vertex shader:</p>
  
  <pre><code>#version 450
  
  out float someFloat;
  
  void main() {
  someFloat = 1.0;
  // some code ...
  }
  </code></pre>
  
  <p>Fragment shader:</p>
  
  <pre><code>#version 450
  
  in float someFloat;
  
  void main() {
  
  // some code using someFloat ...
  }
  </code></pre>
  
  <p>This won't work and always pass zero, while this works:</p>
  
  <p>Vertex shader:</p>
  
  <pre><code> #version 450
  
   layout (location = 0) out float someFloat;
  
   void main() {
  
      someFloat = 1.0;
  
      // some code ...
   }
  </code></pre>
  
  <p>Fragment shader:</p>
  
  <pre><code>#version 450
  
  layout (location = 0) in float someFloat;
  
  void main() {
  
  // Some code using someFloat ...
  }
  </code></pre>
  
  <p>But how can I do this without having to use locations ?</p>