title: WebGL attempt to access out of range vertices in attribute 2 error
body: <p>I know this question has been asked quite a bit, but none of the solutions really fit my case. I am looking to add a second type of object to the canvas with the code shown below. I know I didn't provide much but its a quick start. Just ask for more if you think you have a hunch. This code below is in my render function. </p>
  
  <p>So far I have checked that</p>
  
  <ol>
  <li>I have enough vertices in my points array</li>
  <li>I have enough normal vectors in my normals array</li>
  <li>I have enough texture coordinates in my texCoords array</li>
  <li>There are no mismatches between the vectors added when creating my terrain and my propeller. </li>
  </ol>
  
  <p>The terrain renders just fine with the texture, lighting and all but,I am unable to get the propeller to render. I get the error I listed above. I have added multiple objects to canvases before and never run into an error like this.</p>
  
  <pre><code>//----------------------------------------- Draw Terrain ------------------------------------
    var i = 0;
    for(var row=0-dimension; row&lt;dimension; row+=3){
      for(var col=0-dimension; col&lt;dimension; col+=3, i++){
        var mv = mult(viewer, mult(translate(row, -1, col), mult(scale[i],rot[i])));
        gl.uniformMatrix4fv(modelViewLoc, false, flatten(mv));
        gl.uniformMatrix3fv(normalLoc, false, flatten(normalMatrix(mv, true)));
        gl.drawArrays( gl.TRIANGLES, 0, index);
      }
    }
  
    //----------------------------------------- Draw Propeller ------------------------------------
    mv = mult(viewer, mult( translate(-2.1, -2.9, -.2), scalem(4,5,5)));
    gl.uniformMatrix4fv(modelViewLoc, false, flatten(mv));
    gl.uniformMatrix3fv(normalLoc, false, flatten(normalMatrix(mv, true)));
    gl.drawArrays( gl.TRIANGLES, propellerStart, points.length);
  </code></pre>
  
  <p>Is there any way i can use the "Attribute 2" in the error message to track down the variable giving me this issue?</p>
  
  <p>Appreciate the help!</p>