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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.
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<html>
<head>
<meta charset="utf-8">
<title>Test drawBuffers, readBuffer, and fbo completeness</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>
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<body>
<div id="description"></div>
<div id="console"></div>
<canvas id="canvas" width="20" height="20"> </canvas>
<script>
// In MacOSX, if drawBuffers() and readBuffer() both select an attachment with no image attached,
// fbo becomes incomplete. However, drawBuffers() and readBuffer() should not affect fbo completeness.

"use strict";
description("This tests drawBuffers, readBuffer, and fbo completeness");

var setupRenderbuffer = function(attachment) {
  var renderbuffer = gl.createRenderbuffer();
  gl.bindRenderbuffer(gl.RENDERBUFFER, renderbuffer);
  gl.framebufferRenderbuffer(gl.FRAMEBUFFER, attachment, gl.RENDERBUFFER, renderbuffer);
  gl.renderbufferStorage(gl.RENDERBUFFER, gl.RGBA8, canvas.width, canvas.height);
  return renderbuffer;
}

var wtu = WebGLTestUtils;
var canvas = document.getElementById("canvas");
var gl = wtu.create3DContext(canvas, undefined, 2);
if (!gl) {
  testFailed("context does not exist");
} else {
  testPassed("context exists");

  var fb = gl.createFramebuffer();
  gl.bindFramebuffer(gl.FRAMEBUFFER, fb);

  debug("fbo with two color images attached should be complete");
  var colorbuffer = setupRenderbuffer(gl.COLOR_ATTACHMENT0);
  var colorbuffer1 = setupRenderbuffer(gl.COLOR_ATTACHMENT1);
  shouldBe('gl.checkFramebufferStatus(gl.FRAMEBUFFER)', 'gl.FRAMEBUFFER_COMPLETE');

  debug("drawBuffers selects ATTACHMENT1, fbo should be complete");
  gl.drawBuffers([gl.NONE, gl.COLOR_ATTACHMENT1]);
  shouldBe('gl.checkFramebufferStatus(gl.FRAMEBUFFER)', 'gl.FRAMEBUFFER_COMPLETE');

  debug("remove image attached to ATTACHMENT1, fbo should be complete");
  gl.framebufferRenderbuffer(gl.FRAMEBUFFER, gl.COLOR_ATTACHMENT1, gl.RENDERBUFFER, null);
  shouldBe('gl.checkFramebufferStatus(gl.FRAMEBUFFER)', 'gl.FRAMEBUFFER_COMPLETE');

  debug("set read buffer to ATTACHMENT1, fbo should be complete");
  gl.readBuffer(gl.COLOR_ATTACHMENT1);
  shouldBe('gl.checkFramebufferStatus(gl.FRAMEBUFFER)', 'gl.FRAMEBUFFER_COMPLETE');

  debug("drawBuffers selects ATTACHMENT0, fbo should be complete");
  gl.drawBuffers([gl.COLOR_ATTACHMENT0]);
  shouldBe('gl.checkFramebufferStatus(gl.FRAMEBUFFER)', 'gl.FRAMEBUFFER_COMPLETE');

  debug("drawBuffers selects ATTACHMENT1, fbo should be complete");
  gl.drawBuffers([gl.NONE, gl.COLOR_ATTACHMENT1]);
  shouldBe('gl.checkFramebufferStatus(gl.FRAMEBUFFER)', 'gl.FRAMEBUFFER_COMPLETE');

  debug("set read buffer to ATTACHMENT0, fbo should be complete");
  gl.readBuffer(gl.COLOR_ATTACHMENT0);
  shouldBe('gl.checkFramebufferStatus(gl.FRAMEBUFFER)', 'gl.FRAMEBUFFER_COMPLETE');

  gl.deleteFramebuffer(fb);
  gl.deleteRenderbuffer(colorbuffer);
  gl.deleteRenderbuffer(colorbuffer1);

  wtu.glErrorShouldBe(gl, gl.NO_ERROR, "should be no error after setup and clear render buffer");
}

debug("");
var successfullyParsed = true;

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

</body>
</html>
