实现思路：通过uniform对象，每次画面刷新的时候，把偏移值由CPU传入GPU
关键代码：
Shader.vs
#version 330 core
layout (location = 0) in vec3 position;
uniform vec3 offset;
void main()
{
gl_Position = vec4(position+offset, 1.0);
}
// Game loop
while (!glfwWindowShouldClose(window))
{
// Check if any events have been activiated (key pressed, mouse moved etc.) and call corresponding response functions
glfwPollEvents();
// Render
// Clear the colorbuffer
glClearColor(0.2f, 0.3f, 0.3f, 1.0f);
glClear(GL_COLOR_BUFFER_BIT);
// Draw our first triangle
shader.Use();
glBindVertexArray(VAO);
glDrawArrays(GL_TRIANGLES, 0, 3);
GLfloat timeValue = glfwGetTime();
GLfloat x = (sin(timeValue) / 2);
GLint vertexOffsetLocation = glGetUniformLocation(shader.Program, "offset");
glUniform3f(vertexOffsetLocation, x, 0, 0.0f);
glBindVertexArray(0);
// Swap the screen buffers
glfwSwapBuffers(window);
}
glGetUniformLocation返回shader里面uniform句柄，接下来就使用glUniformXXX給它传值。
