xyz;
      vEyeVector = -vec3(vertex.xyz);
      gl_Position = uProjectionMatrix * uModelViewMatrix * vec4(aVertexPosition, 1.0);
    }
  </script>

  <script id="fragment-shader" type="x-shader/x-fragment">
    #version 300 es
    precision mediump float;

    uniform bool uWireframe;
    uniform vec4 uLightAmbient;
    uniform vec4 uLightDiffuse;
    uniform vec4 uLightSpecular;
    uniform vec4 uMaterialAmbient;
    uniform vec4 uMaterialDiffuse;
    uniform vec4 uMaterialSpecular;
    uniform float uShi