GLuint LoadShader(const char *shaderSrc, GLenum type)
{
   GLuint shader;
   GLint compiled;

   // Create the shader object
   shader = glCreateShader(type);

   if(shader == 0)
      return 0;

   // Load the shader source
   glShaderSource(shader, 1, &shaderSrc, NULL);

   // Compile the shader
   glCompileShader(shader);

   // Check the compile status
   glGetShaderiv(shader, GL_COMPILE_STATUS, &compiled);

   if(!compiled)
   {
      GLint infoLen = 0;

      glGetShaderiv(shader, GL_INFO_LOG_LENGTH, &infoLen);

      if(infoLen > 1)
      {
         char* infoLog = malloc(sizeof(char) * infoLen);

         glGetShaderInfoLog(shader, infoLen, NULL, infoLog);
         esLogMessage("Error compiling shader:\n%s\n", infoLog);
         free(infoLog);
      }

      glDeleteShader(shader);
      return 0;
   }

   return shader;

}

int Init(ESContext *esContext)
   UserData *userData = esContext->userData;
   GLbyte vShaderStr[] =
      "attribute vec4 vPosition;   \n"
      "void main()                 \n"
      "{                           \n"
      "  gl_Position = vPosition;  \n"
      "}                           \n";

   GLbyte fShaderStr[] =
      "precision mediump float;                   \n"
      "void main()                                \n"
      "{                                          \n"
      "  gl_FragColor = vec4(1.0, 0.0, 0.0, 1.0); \n"
      "}                                          \n";

   GLuint vertexShader;
   GLuint fragmentShader;
   GLuint programObject;
   GLint linked;

  // Load the vertex/fragment shaders
  vertexShader = LoadShader(GL_VERTEX_SHADER, vShaderStr);
  fragmentShader = LoadShader(GL_FRAGMENT_SHADER, fShaderStr);

  // Create the program object
  programObject = glCreateProgram();

  if(programObject == 0)
     return 0;

  glAttachShader(programObject, vertexShader);
  glAttachShader(programObject, fragmentShader);

  // Bind vPosition to attribute 0
  glBindAttribLocation(programObject, 0, "vPosition");

  // Link the program
  glLinkProgram(programObject);

  // Check the link status
  glGetProgramiv(programObject, GL_LINK_STATUS, &linked);

  if(!linked)
  {
     GLint infoLen = 0;

     glGetProgramiv(programObject, GL_INFO_LOG_LENGTH, &infoLen);

     if(infoLen > 1)
     {
        char* infoLog = malloc(sizeof(char) * infoLen);

        glGetProgramInfoLog(programObject, infoLen, NULL, infoLog);
        esLogMessage("Error linking program:\n%s\n", infoLog);

        free(infoLog);
     }

     glDeleteProgram(programObject);
     return FALSE;
  }

  // Store the program object
  userData->programObject = programObject;

  glClearColor(0.0f, 0.0f, 0.0f, 1.0f);
  return TRUE;

glUseProgram(userData->programObject);

// Load the vertex data
glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 0, vVertices);
glEnableVertexAttribArray(0);

glDrawArrays(GL_TRIANGLES, 0, 3);