<!DOCTYPE HTML>
<meta http-equiv="content-type" content="text/html; charset=utf-8" />

<title>WebGL test: Drawing with a null program</title>

<script src="/tests/SimpleTest/SimpleTest.js"></script>
<link rel="stylesheet" href="/tests/SimpleTest/test.css">
<script src="driver-info.js"></script>
<script src="webgl-util.js"></script>


<script id="vs" type="x-shader/x-vertex">

void main(void) {
  gl_PointSize = 16.0;
  gl_Position = vec4(0.0, 0.0, 0.0, 1.0);
}

</script>
<script id="fs" type="x-shader/x-fragment">

precision mediump float;

void main(void) {
  gl_FragColor = vec4(0.0, 1.0, 0.0, 1.0);
}

</script>
<body>
<canvas id="c" width="64" height="64"></canvas>
<script>

// Give ourselves a scope to return early from:
(function() {
  var gl = c.getContext('webgl');
  if (!gl) {
    todo(false, 'WebGL is unavailable.');
    return;
  }

  gl.disable(gl.DEPTH_TEST);

  var prog   = WebGLUtil.createProgramByIds(gl, 'vs', 'fs');
  if (!prog) {
    ok(false, 'Program linking should succeed.');
    return;
  }

  function checkGLError(func, info, refValue) {
    if (!refValue)
      refValue = 0;

    var error = gl.getError();
    func(error == refValue,
         '[' + info + '] gl.getError should be 0x' + refValue.toString(16) +
                                        ', was 0x' + error.toString(16) + '.');
  }

  // Start drawing
  checkGLError(ok, 'after setup');

  gl.useProgram(prog);
  gl.drawArrays(gl.POINTS, 0, 1);
  checkGLError(ok, 'after non-null-program DrawArrays');

  gl.useProgram(null);
  gl.drawArrays(gl.POINTS, 0, 1);
  checkGLError(ok, 'after null-program DrawArrays', gl.INVALID_OPERATION);

  ok(true, 'Test complete.');
})();

</script>

