n 300 es
    precision mediump float;

    uniform mat4 uModelViewMatrix;
    uniform mat4 uProjectionMatrix;
    uniform mat4 uNormalMatrix;
    uniform vec3 uLightPosition;
    uniform vec4 uMaterialDiffuse;
    uniform bool uWireframe;
    uniform bool uUpdateLight;

    in vec3 aVertexPosition;
    in vec3 aVertexNormal;
    in vec4 aVertexColor;

    out vec3 vNormal;
    out vec3 vLightRay;
    out vec3 vEyeVector;
    out vec4 vFinalColor;

    void main(void) {
      // If wireframe is enabled, set 