| <!-- |
| 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>ColorMask Must Be Preserved During Implicit Clears</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> |
| <script> |
| "use strict"; |
| const wtu = WebGLTestUtils; |
| const sz = 128; |
| let frames; |
| let gl; |
| let tests = [ |
| { alpha: false, antialias: false, premultipliedAlpha: false }, |
| { alpha: false, antialias: false, premultipliedAlpha: true }, |
| { alpha: false, antialias: true, premultipliedAlpha: false }, |
| { alpha: false, antialias: true, premultipliedAlpha: true }, |
| ]; |
| let currentTest; |
| let testIndex = 0; |
| |
| function initTest() { |
| description(); |
| debug('ColorMask must be preserved during implicit clears of textures.'); |
| debug('Regression test for <a href="http://crbug.com/911918">http://crbug.com/911918</a>'); |
| |
| requestAnimationFrame(nextTest); |
| } |
| |
| function nextTest() { |
| if (testIndex >= tests.length) { |
| finishTest(); |
| return; |
| } |
| |
| frames = 20; |
| let canvases = document.getElementById('canvases'); |
| let canvas = document.createElement('canvas'); |
| canvas.width = sz; |
| canvas.height = sz; |
| canvases.appendChild(canvas); |
| currentTest = tests[testIndex]; |
| ++testIndex; |
| gl = wtu.create3DContext(canvas, currentTest); |
| requestAnimationFrame(runTest); |
| } |
| |
| function runTest() { |
| // Create a user-defined framebuffer which has an alpha channel. |
| let fb = gl.createFramebuffer(); |
| gl.bindFramebuffer(gl.FRAMEBUFFER, fb); |
| // Set color mask to disable alpha writes. This is important; see below. |
| gl.colorMask(true, true, true, false); |
| let tex = gl.createTexture(); |
| gl.bindTexture(gl.TEXTURE_2D, tex); |
| gl.texImage2D(gl.TEXTURE_2D, 0, gl.RGBA, sz, sz, 0, gl.RGBA, gl.UNSIGNED_BYTE, null); |
| gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_MAG_FILTER, gl.NEAREST); |
| gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_MIN_FILTER, gl.NEAREST); |
| // Upload a sub-rectangle. In Chrome, this was lazily clearing level 0 of the |
| // texture using OpenGL, setting the driver's color mask to (true, true, true, |
| // true) in the process. Because the user's color mask was set to (true, true, |
| // true, false) above, incorrect caching code was failing to reset the |
| // driver's color mask later. On macOS, Chrome implements alpha:false WebGL |
| // contexts on top of RGBA textures whose alpha channel is cleared to 1.0 and |
| // where the color mask is set to (true, true, true, false) during all writes. |
| // This bug was allowing that texture's alpha channel to be destroyed. |
| gl.texSubImage2D(gl.TEXTURE_2D, 0, 0, 0, 1, 1, gl.RGBA, gl.UNSIGNED_BYTE, new Uint8Array(4)); |
| gl.framebufferTexture2D(gl.FRAMEBUFFER, gl.COLOR_ATTACHMENT0, gl.TEXTURE_2D, tex, 0); |
| // We have to issue one clear to this framebuffer to get the color mask |
| // latched into the internal caching code. |
| gl.clear(gl.COLOR_BUFFER_BIT); |
| |
| // Switch back to default framebuffer. |
| gl.bindFramebuffer(gl.FRAMEBUFFER, null); |
| // Set clear color to transparent green. |
| gl.clearColor(0, 1, 0, 0); |
| // Clear. Result should be opaque green. Was transparent green when |
| // bug was encountered. |
| gl.clear(gl.COLOR_BUFFER_BIT); |
| wtu.checkCanvasRect(gl, 0, 0, sz, sz, |
| [ 0, 255, 0, 255 ], |
| "default framebuffer should be opaque green for " + JSON.stringify(currentTest)); |
| |
| gl.deleteFramebuffer(fb); |
| gl.deleteTexture(tex); |
| |
| --frames; |
| if (frames == 0) { |
| requestAnimationFrame(nextTest); |
| } else { |
| requestAnimationFrame(runTest); |
| } |
| } |
| |
| requestAnimationFrame(initTest); |
| </script> |
| </head> |
| <body> |
| <div id="description"></div> |
| <div id="canvases"></div> |
| <div id="console"></div> |
| </body> |
| </html> |
