Could not initialise shaders when adding texture

Hi All,

I want to map a texture to the sphere. However, I encounter a problem. The program only prompts “Could not initialise shaders”.

Is there any mistake I made in the program? Can anyone help me to check it? Thanks for your help.

<script id="shader-fs" type="x-shader/x-fragment"> 
  #ifdef GL_ES
  precision highp float;
  varying vec4 vTransformedNormal;
  varying vec4 vPosition;

  uniform vec3 uAmbientColor;
  uniform vec3 uPointLightingLocation;
  uniform vec3 uPointLightingSpecularColor;
  uniform vec3 uPointLightingDiffuseColor;

  varying vec4 vColor;
  varying vec2 vTextureCoord;
  varying vec3 vLightWeighting;
  uniform sampler2D uSampler;
  void main(void) {
    vec3 lightWeighting;
    vec3 lightDirection = normalize(uPointLightingLocation -;
    vec3 normal = normalize(;
      float specularLightWeighting = 0.0;
      float shininess = 32.0;
      if (shininess < 255.0) {
        vec3 eyeDirection = normalize(;
        vec3 reflectionDirection = reflect(-lightDirection, normal);
        specularLightWeighting = pow(max(dot(reflectionDirection, eyeDirection), 0.0), shininess);
      float diffuseLightWeighting = max(dot(normal, lightDirection), 0.0);
      lightWeighting = uAmbientColor + uPointLightingSpecularColor * specularLightWeighting + uPointLightingDiffuseColor * diffuseLightWeighting;

    gl_FragColor = vec4(vColor.rgb * lightWeighting, vColor.a);
    vec4 textureColor = texture2D(uSampler, vec2(vTextureCoord.s, vTextureCoord.t));
    gl_FragColor = vec4(textureColor.rgb * vLightWeighting, textureColor.a);

 <script id="shader-vs" type="x-shader/x-vertex"> 
  attribute vec3 aVertexPosition;
  attribute vec3 aVertexNormal;
  attribute vec4 aVertexColor;
  attribute vec2 aTextureCoord;

  uniform mat4 uMVMatrix;
  uniform mat4 uPMatrix;
  uniform mat4 uNMatrix;

  varying vec4 vColor;
  varying vec4 vTransformedNormal;
  varying vec4 vPosition;
  varying vec2 vTextureCoord;
  void main(void) {
    vPosition = uMVMatrix * vec4(aVertexPosition, 1.0);
    gl_Position = uPMatrix * vPosition;
    vColor = aVertexColor;
    vTextureCoord = aTextureCoord;
    vTransformedNormal = uNMatrix * vec4(aVertexNormal, 1.0);

var shaderProgram;
function initShaders() {
    var fragmentShader = getShader(gl, "shader-fs");
    var vertexShader = getShader(gl, "shader-vs");

    shaderProgram = gl.createProgram();
    gl.attachShader(shaderProgram, vertexShader);
    gl.attachShader(shaderProgram, fragmentShader);

    if (!gl.getProgramParameter(shaderProgram, gl.LINK_STATUS)) {
        alert("Could not initialise shaders");