| <!-- |
| 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"> |
| <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="testbed" width="400" height="400" style="width: 40px; height: 40px;"></canvas> |
| <div id="description"></div> |
| <div id="console"></div> |
| <script> |
| "use strict"; |
| var wtu = WebGLTestUtils; |
| description('Verify renderbuffers are initialized to 0 before being read in WebGL'); |
| |
| var gl = wtu.create3DContext("testbed"); |
| if (!gl) { |
| testFailed('canvas.getContext() failed'); |
| } else { |
| // Set the clear color to green. It should never show up. |
| gl.clearColor(0, 1, 0, 1); |
| |
| runTest(gl, gl.canvas.width, gl.canvas.height, 0); |
| runTest(gl, gl.canvas.width, gl.canvas.height, 1); |
| runTest(gl, gl.canvas.width, gl.canvas.height, 0); |
| runTest(gl, gl.canvas.width, gl.canvas.height, 1); |
| |
| // Testing buffer clearing won't change the clear values. |
| var clearColor = gl.getParameter(gl.COLOR_CLEAR_VALUE); |
| shouldBe("clearColor", "[0, 1, 0, 1]"); |
| wtu.glErrorShouldBe(gl, gl.NO_ERROR, 'should be no errors'); |
| } |
| |
| function runTest(gl, width, height, order) |
| { |
| wtu.checkCanvasRect(gl, 0, 0, width, height, [0,0,0,0], |
| "internal buffers have been initialized to 0"); |
| |
| // fill the back buffer so we know that reading below happens from |
| // the renderbuffer. |
| gl.clear(gl.COLOR_BUFFER_BIT); |
| |
| var fbo = gl.createFramebuffer(); |
| gl.bindFramebuffer(gl.FRAMEBUFFER, fbo); |
| var colorbuffer = gl.createRenderbuffer(); |
| gl.bindRenderbuffer(gl.RENDERBUFFER, colorbuffer); |
| switch (order) { |
| case 0: |
| allocStorage(width, height); |
| attachBuffer(colorbuffer); |
| break; |
| case 1: |
| attachBuffer(colorbuffer); |
| allocStorage(width, height); |
| break; |
| } |
| |
| function allocStorage(width, height) { |
| gl.renderbufferStorage(gl.RENDERBUFFER, gl.RGBA4, width, height); |
| wtu.glErrorShouldBe(gl, gl.NO_ERROR, 'should be no error after renderbufferStorage(internalformat = RGBA4).'); |
| } |
| |
| function attachBuffer(colorbuffer) { |
| gl.framebufferRenderbuffer(gl.FRAMEBUFFER, gl.COLOR_ATTACHMENT0, gl.RENDERBUFFER, colorbuffer); |
| } |
| |
| if (gl.checkFramebufferStatus(gl.FRAMEBUFFER) != gl.FRAMEBUFFER_COMPLETE) { |
| testFailed('Framebuffer incomplete.'); |
| return; |
| } |
| |
| wtu.checkCanvasRect(gl, 0, 0, width, height, [0,0,0,0], |
| "user buffers have been initialized to 0"); |
| |
| gl.deleteFramebuffer(fbo); |
| gl.deleteRenderbuffer(colorbuffer); |
| |
| // this clear should not matter we are about to resize |
| gl.clear(gl.COLOR_BUFFER_BIT); |
| |
| gl.canvas.width += 1; |
| gl.canvas.height += 1; |
| |
| debug(''); |
| } |
| |
| var successfullyParsed = true; |
| </script> |
| <script src="../../js/js-test-post.js"></script> |
| </body> |
| </html> |
