CONFORMANCE_RULES.txt (6012B)
1 Rules for Claiming a Conformant WebGL Implementation 2 ==================================================== 3 4 The WebGL API is a web standard, and many web browser implementers 5 deliver their browser on multiple operating systems (OSs). WebGL 6 implementations also typically rely on the presence of an OpenGL or 7 OpenGL ES implementation on the OS. It can be appreciated that a WebGL 8 implementation therefore has many dependencies. This document attempts 9 to clarify to potential implementers the rules the Khronos Group uses 10 to judge whether a particular WebGL implementation is conformant. 11 12 There are two primary reasons to submit conformance results: 13 14 A) A web browser implementer desires to certify their WebGL 15 implementation as conformant. 16 17 B) A GPU manufacturer delivering an embedded system including web 18 browser with WebGL support desires to certify their WebGL 19 implementation as conformant. 20 21 Each of these situations carries different constraints, so the 22 conformance rules are phrased differently for each. Typically, a web 23 browser implementer aims to certify that the WebGL "layer" is correct. 24 A GPU vendor typically aims to certify that a given device is 25 physically capable of passing the tests. 26 27 A newly-developed WebGL implementation should not support the "webgl" 28 HTML Canvas context type by default in a shipping version of the 29 product until reaching conformance. It is acceptable to give end users 30 an option to turn on WebGL support in a non-conformant implementation 31 as long as the documentation for that option clearly indicates that 32 the implementation is not yet conformant and may have compatibility 33 issues. It is suggested that the Canvas context type 34 "experimental-webgl" may be supported by default in such 35 implementations. 36 37 A WebGL implementation might reach conformance, but a subsequent 38 graphics driver release on a particular OS might introduce a 39 regression causing failures of one or more of the WebGL conformance 40 tests. In this situation it is not required to revoke support for the 41 "webgl" HTML Canvas context type. The WebGL implementer should work 42 with the GPU vendor to ensure the driver regression is fixed. A 43 situation like this would, however, prevent the WebGL implementer from 44 conforming to a subsequent version of the test suite. 45 46 (A) Conformance Rules for a Web Browser Implementer 47 =================================================== 48 49 1. Conformance on a particular operating system 50 51 On a given OS, a WebGL implementation will be considered to conform to 52 a particular version of the conformance suite if the suite passes with 53 no test failures on at least two GPUs, each from a different 54 vendor. If the OS only supports a GPU from one vendor, the two-GPU 55 requirement is dropped. 56 57 2. Conformance across multiple operating systems 58 59 A WebGL implementation will be considered to conform to a particular 60 version of the conformance suite if it passes rule (1) on all of the 61 OSs on which the WebGL implementation is intended to be supported. 62 63 3. Conformance as the web browser is upgraded 64 65 WebGL conformance results submitted for an earlier version of the 66 browser carry forward to later versions of the browser that do not 67 cause any previously passing test to fail. 68 69 4. Conformance as the operating system is upgraded 70 71 If a new version is released of one of the OSs on which a WebGL 72 implementation is intended to run, then WebGL conformance results 73 submitted for earlier versions of that OS carry forward. Future 74 conformance results must be submitted against the new version of the 75 OS. If it is anticipated that the older OS version will be supported 76 for some time, then future conformance results must be submitted 77 separately for both the old and new versions of the OS. 78 79 (B) Conformance Rules for a GPU Vendor 80 ====================================== 81 82 A GPU vendor submitting conformance results for a WebGL implementation 83 typically does so because the device containing the GPU includes a 84 built-in web browser. In this case the following rules apply: 85 86 1. Conformance results must be submitted for each GPU and operating 87 system combination to be certified. It is not required to submit 88 results for different devices containing the same GPU and running the 89 same operating system that do not cause any previously passing test to 90 fail. 91 92 2. Conformance results carry forward for a given GPU as the operating 93 system and graphics driver are upgraded but do not cause any previously 94 passing test to fail. 95 96 Discussion 97 ========== 98 99 A WebGL implementation intended to ship on three OSs may reach 100 conformance on two of them, but due to graphics driver bugs, may be 101 unable to reach conformance on the third. In this situation the 102 implementation is not yet considered to be conformant. 103 104 An existing WebGL implementation which conformed to an earlier version 105 of the test suite is not required to remove support for the "webgl" 106 HTML Canvas context type while in the process of conforming to a later 107 version of the test suite. However, the implementer must not advertise 108 conformance to the later version until it has been reached. It is 109 acceptable for the implementer to advertise details of their 110 conformance, for example number or percentage of passing or failing 111 tests, or names of passing or failing tests. 112 113 A GPU vendor might submit conformance results in order to use the 114 WebGL logo in a marketing campaign. In this situation, results may be 115 submitted in advance of the product becoming available through sales 116 channels, per the rules above. 117 118 The WebGL API has strict security requirements. Even one failing test 119 may indicate a serious security issue in the WebGL implementation. For 120 this reason, no exceptions for failing conformance tests will be 121 granted. 122 123 The Khronos Group determines whether a particular WebGL implementation 124 is conformant based on the implementer's conformance suite 125 submissions, on multiple OSs and on multiple GPUs as necessary, using 126 the rules above. An implementer shall not judge their own 127 implementation conformant simply by applying the above rules.