//創(chuàng)建一個buffer
let buffer = gl.createBuffer();
//綁定buffer
gl.bindBuffer(gl.ARRAY_BUFFER, buffer);

let vertices = [
    ......
];
vertices = new Float32Array(vertices); //創(chuàng)建一個float對象
//傳數據
gl.bufferData(gl.ARRAY_BUFFER, vertices, gl.STATIC_DRAW);

let vertices = [
  -0.5,
  0.0,
  1.0,
  0.0,
  0.0, //頂點1
  0.0,
  0.8,
  0.0,
  1.0,
  0.0, //頂點2
  0.5,
  0.0,
  0.0,
  0.0,
  1.0, //頂點3
];
//頂點著色器,聲明a_position和a_Color的attribute屬性，v_Color的varying屬性
let vertexShader = ` 
  attribute vec2 a_position;
  attribute vec3 a_Color;
  varying vec3 v_Color;
  void main(){
    v_Color = a_Color;
    gl_Position = vec4(a_position,0.0,1.0);
  }
`;
//片源著色器
let fragmentShader = `
    precision mediump float;
    varying vec3 v_Color;
    void main() {
     gl_FragColor = vec4(v_Color,1.0);
    }
`;

//把buffer賦值給attribute
let a_position = gl.getAttribLocation(webgl.program, "a_position");
let a_Color = gl.getAttribLocation(webgl.program, "a_Color");
gl.vertexAttribPointer(
  a_position, //vertexshader里面的變量的地址
  2, //size:attribute變量的長度(幾個一組)
  gl.FLOAT, //數據類型 float
  false, //歸一化 相當于length等于1
  FSIZE * 5, //stride:每個點（組）的信息所占用的字節(jié)BYTES
  0 // offset:偏移（從第幾個開始）
);
gl.vertexAttribPointer(a_Color, 3, gl.FLOAT, false, FSIZE * 5, FSIZE * 2);
//確認賦值
gl.enableVertexAttribArray(a_position);
gl.enableVertexAttribArray(a_Color);

//畫三角形
gl.drawArrays(gl.TRIANGLES, 0, 3);