precision mediump float;
    varying vec4 v_Normal;
    varying vec4 v_position;
    uniform vec3 u_PointLightPosition;
    uniform vec3 u_DiffuseLight;
    uniform vec3 u_AmbientLight;
    void main(void){
    vec3 normal = normalize(v_Normal.xyz);
    vec3 lightDirection = normalize(u_PointLightPosition - vec3(v_position.xyz));
    float nDotL = max(dot(lightDirection, normal), 0.0);
    vec3 diffuse = u_DiffuseLight * vec3(1.0,0,1.0)* nDotL;
    vec3 ambient = u_AmbientLight * vec3(1.0,0,1.0);
      gl_FragColor =vec4(diffuse + ambient, 1);
    }按照课程里面的逐片元渲染的情况,点位和向量都是从顶点着色器来的,是不是在片元渲染的时候也是获取的点坐标和向量也是根据差值来
好的,谢谢啦