| <!-- |
| 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> |
| |
| <script> |
| "use strict"; |
| |
| // These declarations need to be global for "shouldBe" to see them |
| var gl; |
| var pixel = [0, 0, 0, 1]; |
| var canvas; |
| |
| function init() |
| { |
| description('Verify that changing the size of an antialiased WebGL context does not cause it to stop working.'); |
| |
| runTest(); |
| } |
| |
| function getWebGL(canvasWidth, canvasHeight, contextAttribs) |
| { |
| canvas = document.createElement("canvas"); |
| if (!canvas) |
| return null; |
| canvas.width = canvasWidth; |
| canvas.height = canvasHeight; |
| |
| gl = WebGLTestUtils.create3DContext(canvas, contextAttribs); |
| if (!gl) |
| return null; |
| |
| return gl; |
| } |
| |
| function runTest() |
| { |
| shouldBeNonNull("gl = getWebGL(1, 1, { alpha: false, antialias: true })"); |
| |
| // Clear to black. |
| gl.clearColor(0.0, 0.0, 0.0, 1.0); |
| gl.clear(gl.COLOR_BUFFER_BIT); |
| |
| // Check that the pixel's R channel is 0. |
| var buf = new Uint8Array(1 * 1 * 4); |
| gl.readPixels(0, 0, 1, 1, gl.RGBA, gl.UNSIGNED_BYTE, buf); |
| pixel[0] = buf[0]; |
| shouldBeTrue("pixel[0] == 0"); |
| |
| // Change the size of the canvas. |
| canvas.width = 3; |
| canvas.height = 3; |
| |
| // Clear to black. |
| gl.clearColor(0.0, 0.0, 0.0, 1.0); |
| gl.clear(gl.COLOR_BUFFER_BIT); |
| |
| // Clear the top-left pixel to white. |
| gl.enable(gl.SCISSOR_TEST); |
| gl.scissor(0, 0, 1, 1); |
| gl.clearColor(1.0, 1.0, 1.0, 1.0); |
| gl.clear(gl.COLOR_BUFFER_BIT); |
| |
| // Check that the top-left pixel has R channel 255. |
| gl.readPixels(0, 0, 1, 1, gl.RGBA, gl.UNSIGNED_BYTE, buf); |
| pixel[0] = buf[0]; |
| shouldBeTrue("pixel[0] == 255"); |
| |
| // Check that the bottom-right pixel has R channel 0. |
| gl.readPixels(2, 2, 1, 1, gl.RGBA, gl.UNSIGNED_BYTE, buf); |
| pixel[0] = buf[0]; |
| shouldBeTrue("pixel[0] == 0"); |
| |
| finishTest(); |
| } |
| |
| </script> |
| </head> |
| <body onload="init()"> |
| <div id="description"></div> |
| <div id="console"></div> |
| </body> |
| </html> |
