<!--
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>WebGL Scissor Canvas Dimensions 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>
<style>
canvas {
    border: 1px solid #000;
    width: 64px;
    height: 64px;
}
</style>
</head>
<body>
<canvas id="canvas1" width="16" height="16"> </canvas>
<canvas id="canvas2" width="16" height="16"> </canvas>
<div id="description"></div>
<div id="console"></div>
<script>
"use strict";
description("Check that scissoring is initially disabled and that the scissor rect does not change when canvas size changes.");

var wtu = WebGLTestUtils;

function testInit(canvas, attribs) {
  var gl = wtu.create3DContext(canvas, attribs);
  if (!gl) {
    testFailed("context does not exist");
    return;
  }
  debug("Testing that scissor test is initially disabled");
  // Setting the scissor rect should have no effect on drawing.
  gl.scissor(0, 0, 1, 1);
  gl.clearColor(0, 1, 0, 1);
  gl.clear(gl.COLOR_BUFFER_BIT);
  wtu.glErrorShouldBe(gl, gl.NO_ERROR, "there should be no errors");
  wtu.checkCanvasRect(gl, 0, 0, canvas.width, canvas.height, [0, 255, 0, 255], "whole canvas should be green");
}

function testCanvasSizeChange(canvas, attribs) {
  var gl = wtu.create3DContext(canvas, attribs);
  if (!gl) {
    testFailed("context does not exist");
    return;
  }
  debug("Testing that scissor rect dimensions do not change if the canvas is resized.");
  canvas.width = 32;
  canvas.height = 32;
  gl.viewport(0, 0, 32, 32);
  gl.enable(gl.SCISSOR_TEST);
  gl.clearColor(0, 1, 0, 1);
  gl.clear(gl.COLOR_BUFFER_BIT);
  wtu.glErrorShouldBe(gl, gl.NO_ERROR, "there should be no errors");
  wtu.checkCanvasRect(gl, 0, 0, 16, 16, [0, 255, 0, 255], "area inside scissor should be green");
  wtu.checkCanvasRect(gl, 0, 16, 32, 16, [0, 0, 0, 0], "area outside scissor should be black");
  wtu.checkCanvasRect(gl, 16, 0, 16, 16, [0, 0, 0, 0], "area outside scissor should be black");
}

testInit(document.getElementById("canvas1"), {antialias: false});
debug("");
testCanvasSizeChange(document.getElementById("canvas2"), {antialias: false});

var successfullyParsed = true;

</script>
<script src="../../js/js-test-post.js"></script>

</body>
</html>
