val vertices = Array(
      -0.5f, 0.5f, 0f, 1f, 0f, 0f,
      -0.5f, -0.5f, 0f, 0f, 1f, 0f,
      0.5f, -0.5f, 0f, 0f, 0f, 1f,

      0.5f, -0.5f, 0f, 0f, 0f, 1f,
      0.5f, 0.5f, 0f, 0f, 1f, 0f,
      -0.5f, 0.5f, 0f, 1f, 0f, 0f
    )

    val buffer = BufferUtils.createFloatBuffer(vertices.length)
    buffer.put(vertices)
    buffer.flip()

    val vao = GL30.glGenVertexArrays()
    GL30.glBindVertexArray(vao)

    val vbo = GL15.glGenBuffers()
    GL15.glBindBuffer(GL15.GL_ARRAY_BUFFER, vbo)
    GL15.glBufferData(GL15.GL_ARRAY_BUFFER, buffer, GL15.GL_STATIC_DRAW)

    //GL20.glVertexAttribPointer(0, 3, GL11.GL_FLOAT, false, 3*4, 0)

    //GL15.glBindBuffer(GL15.GL_ARRAY_BUFFER, 0)

//    GL30.glBindVertexArray(0)

    val vertexShaderID = GL20.glCreateShader(GL20.GL_VERTEX_SHADER)
    GL20.glShaderSource(vertexShaderID, sourceToString("src\\org\\xulufworld\\game\\vertex_shader.glsl"))
    GL20.glCompileShader(vertexShaderID)

    val fragmentShaderID = GL20.glCreateShader(GL20.GL_FRAGMENT_SHADER)
    GL20.glShaderSource(fragmentShaderID, sourceToString("src\\org\\xulufworld\\game\\fragment_shader.glsl"))
    GL20.glCompileShader(fragmentShaderID)

    val programID = GL20.glCreateProgram()
    GL20.glAttachShader(programID, vertexShaderID)
    GL20.glAttachShader(programID, fragmentShaderID)
    GL30.glBindFragDataLocation(programID, 0, "fragColour")
    GL20.glLinkProgram(programID)

    val status = GL20.glGetProgrami(programID, GL20.GL_LINK_STATUS);
    if (status != GL11.GL_TRUE) {
      throw new RuntimeException(GL20.glGetProgramInfoLog(programID));
    }

    GL20.glUseProgram(programID)
    val posAttrib = GL20.glGetAttribLocation(programID, "position")
    GL20.glEnableVertexAttribArray(posAttrib)
    GL20.glVertexAttribPointer(posAttrib, 3, GL11.GL_FLOAT, false, 6 * 4, 0)

    val colourAttrib = GL20.glGetAttribLocation(programID, "colour")
    GL20.glEnableVertexAttribArray(colourAttrib)
    GL20.glVertexAttribPointer(colourAttrib, 3, GL11.GL_FLOAT, false, 6 * 4, 3 * 4)

    val uniModel = GL20.glGetUniformLocation(programID, "model")
    val model = new Matrix4f()
    GL20.glUniformMatrix4fv(uniModel, false, model.getBuffer)

    val uniView = GL20.glGetUniformLocation(programID, "view")
    val view = new Matrix4f()
    GL20.glUniformMatrix4fv(uniView, false, view.getBuffer)

    val uniProjection = GL20.glGetUniformLocation(programID, "projection")
    val ratio = 640f/480f
    val projection = Matrix4f.orthographic(-ratio, ratio, -1f, 1f, -1f, 1f)
    GL20.glUniformMatrix4fv(uniProjection, false, projection.getBuffer)

    while(GLFW.glfwWindowShouldClose(window) != TRUE) {

      if(resized)
      {
        GL11.glViewport(0, 0, WIDTH, HEIGHT)
        resized = false
        println("Changed viewport")
      }

      GLFW.glfwPollEvents()

      GL11.glClearColor(0.0f, 0.5f, 0.5f, 1)
      GL11.glClear(GL11.GL_COLOR_BUFFER_BIT)

      GL30.glBindVertexArray(vao)
      GL20.glEnableVertexAttribArray(0)

      GL20.glUseProgram(programID)

      GL11.glDrawArrays(GL11.GL_TRIANGLES, 0, 6)

      GL20.glDisableVertexAttribArray(0)
      GL30.glBindVertexArray(0)

      GLFW.glfwSwapBuffers(window)
    }
}