<!--
Copyright (c) 2019 The Khronos Group Inc.
Use of this source code is governed by an MIT-style license that can be
found in the LICENSE.txt file.
-->

<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>Simple Rendering Test</title>
<link rel="stylesheet" href="../../resources/js-test-style.css"/>
<script src="../../js/js-test-pre.js"></script>
<script src="../../js/webgl-test-utils.js"> </script>
</head>
<body>
<canvas id="example" width="50" height="50">
There is supposed to be an example drawing here, but it's not important.
</canvas>
<div id="description"></div>
<div id="console"></div>
<script id="vshader" type="x-shader/x-vertex">
attribute vec4 a_Position;
void main()
{
  gl_Position = a_Position;
}
</script>

<script id="fshader" type="x-shader/x-fragment">
void main()
{
  gl_FragColor = vec4(0,1,0,1);
}
</script>
<script>
"use strict";
var wtu = WebGLTestUtils;
function init()
{
  description();

  var gl = wtu.create3DContext("example");
  var program = wtu.loadProgramFromScript(gl, "vshader", "fshader");
  gl.useProgram(program);
  var loc = gl.getAttribLocation(program, "a_Position");

  var vertexObject = gl.createBuffer();
  gl.bindBuffer(gl.ARRAY_BUFFER, vertexObject);
  gl.bufferData(
    gl.ARRAY_BUFFER,
    new Float32Array(
    [  1,  1,
      -1,  1,
      -1, -1,
       1,  1,
      -1, -1,
       1, -1]),
    gl.STATIC_DRAW);
  gl.enableVertexAttribArray(loc);
  gl.vertexAttribPointer(loc, 2, gl.FLOAT, false, 0, 0);

  gl.clear(gl.COLOR_BUFFER_BIT | gl.DEPTH_BUFFER_BIT);
  wtu.checkCanvas(gl, [0,0,0,0], "should be black", 0);
  gl.drawArrays(gl.TRIANGLES, 0, 6);
  wtu.checkCanvas(gl, [0,255,0,255], "should be green", 0);

  wtu.glErrorShouldBe(gl, gl.NO_ERROR, "there should be no errors");
}

init();
var successfullyParsed = true;
</script>
<script src="../../js/js-test-post.js"></script>

</body>
</html>
