| Name |
| |
| ARB_shading_language_100 |
| |
| Name Strings |
| |
| GL_ARB_shading_language_100 |
| |
| Contact |
| |
| John Kessenich, 3Dlabs, Inc. (johnk 'at' 3dlabs.com) |
| Barthold Lichtenbelt, NVIDIA (blichtenbelt 'at' nvidia.com) |
| Jon Leech, SGI (ljp 'at' sgi.com) |
| |
| Notice |
| |
| Copyright (c) 2003-2013 The Khronos Group Inc. Copyright terms at |
| http://www.khronos.org/registry/speccopyright.html |
| |
| Specification Update Policy |
| |
| Khronos-approved extension specifications are updated in response to |
| issues and bugs prioritized by the Khronos OpenGL Working Group. For |
| extensions which have been promoted to a core Specification, fixes will |
| first appear in the latest version of that core Specification, and will |
| eventually be backported to the extension document. This policy is |
| described in more detail at |
| https://www.khronos.org/registry/OpenGL/docs/update_policy.php |
| |
| IP Status |
| |
| Microsoft claims to own unspecified intellectual property related to |
| programmable shading. |
| |
| Status |
| |
| Complete. Approved by the ARB on June 11, 2003. |
| Updated revision 8 approved by the ARB on June 17, 2004. |
| |
| Version |
| |
| Last Modified Date: April 6, 2004 |
| Revision: 8 |
| |
| Number |
| |
| ARB Extension #33 |
| |
| Dependencies |
| |
| This extension is written against the OpenGL 1.5 Specification |
| |
| ARB_shader_objects, ARB_fragment_shader, and ARB_vertex_shader are |
| required to utilize the OpenGL Shading Language associated with this |
| extension. |
| |
| Overview |
| |
| This extension string indicates that the OpenGL Shading Language is |
| supported. The Shading Language is defined by a separate specification |
| document which can be downloaded from |
| |
| http://www.opengl.org/documentation/oglsl.html |
| |
| Issues |
| |
| 1) How do we indicate revisions in the supported version of the Shading |
| Language? |
| |
| RESOLVED: Add a SHADING_LANGUAGE_VERSION query. This query was not |
| present in the initial version of the extension. Therefore, |
| applications should be prepared to detect an INVALID_ENUM error |
| being raised by glGetString(GL_SHADING_LANGUAGE_VERSION). If this |
| error is raised, but ARB_shading_language_100 is defined in the |
| EXTENSIONS string, the application can assume that the initial |
| release of the Shading Language (1.00, which was numbered "1.051" |
| corresponding to document revision 51) is supported. |
| |
| 2) What is the format of the SHADING_LANGUAGE_VERSION string? How does |
| it map onto the release number of the shading language specification? |
| |
| RESOLVED: Identical to the VERSION string format: |
| "major.minor[.release] [vendor info]". The release number is an |
| optional vendor release number, not the shading language |
| specification document release number (which is never visible to |
| apps). |
| |
| The "1.051" release number of the initial Shading Language |
| specification document corresponds to a SHADING_LANGUAGE_VERSION |
| string of "1.00", since "51" was the revision number of the |
| document, not the minor number. |
| |
| Going forward, the specification and query must always use the same |
| encoding for major and minor numbers. The second release of the |
| specification will be labelled "version 1.10, document revision 55", |
| and the corresponding SHADING_LANGUAGE_VERSION string will be "1.10" |
| (we chose to bump the minor version directly to 10 to avoid problems |
| with leading 0s, and confusion with the old "1.051" document release |
| number). |
| |
| Document release and vendor release numbers need not have any |
| relation to each other, since they represent changes other than |
| functionality, such as bug fixes and optimizations (for the |
| implementation), and typos and errata for the specification). |
| |
| Functional changes to the shading language must always be indicated |
| by an increase in the specification minor version number. Such |
| changes may or may not correspond to changes to the core OpenGL |
| version number as well, depending on whether or not they are visible |
| in the OpenGL API. |
| |
| 3) Should SHADING_LANGUAGE_VERSION be added to the state tables? |
| |
| RESOLVED: Yes. The other GetString queries (VERSION, EXTENSIONS, |
| RENDERER, and VENDOR), which have been omitted in the past, should |
| also be added, along with a new type code for string state values. |
| |
| 4) What should the exact wording of the "IP Status" language be? |
| |
| Microsoft has made claims towards the low-level vertex shader and |
| towards the generic programming framework proposed but not accepted |
| into OpenGL 1.4, although that framework did not specify an actual |
| shading language. Additional verbal statements made by Dave Aronson |
| suggest that Microsoft may feel its claims extend to all |
| programmable shading implementations. In fairness to implementers, |
| we need to note the possibility of such a claim while also noting |
| our lack of any specific information about what IP is being claimed. |
| |
| New Tokens |
| |
| Accepted by the <name> parameter of GetString: |
| |
| SHADING_LANGUAGE_VERSION_ARB 0x8B8C |
| |
| Additions to Chapter 6 of the OpenGL 1.5 Specification (State and State |
| Requests) |
| |
| Modify Section 6.1.11, Pointer and String Queries |
| |
| ... returns a pointer to a static string describing some aspect of the |
| current GL connection(1). |
| {footnote 1: Applications making copies of these static strings |
| should never use a fixed-length buffer, because the strings may grow |
| unpredictably over time resulting in buffer overflow when copying. |
| This is particularly true of the EXTENSIONS string, which has become |
| extremely long in some GL implementations.} |
| The possible values for <name> are VENDOR, RENDERER, VERSION, |
| SHADING_LANGUAGE_VERSION, and EXTENSIONS. The format of the RENDERER and |
| VENDOR strings is implementation dependent. The EXTENSIONS string |
| contains a space separated list of extension names (the extension names |
| themselves do not contain any spaces). The VERSION and |
| SHADING_LANGUAGE_VERSION strings are laid out as follows: |
| |
| <version number><space><vendor-specific information> |
| |
| The version number is either of the form <major_number.minor_number> or |
| <major_number.minor_number.release_number>, where the numbers all have |
| one or more digits. The <release_number> and vendor specific information |
| are optional. However, if present, then they pertain to the server and |
| their format and contents are implementation dependent. |
| |
| |
| Add to Table 6.3, State variable types |
| |
| Type code Explanation |
| --------- ---------------------- |
| S NULL-terminated string |
| |
| Errors |
| |
| The error INVALID_ENUM may be generated by GetString if <name> is |
| SHADING_LANGUAGE_VERSION, but only the initial version of this extension |
| is supported. In this case, the implementation will support the initial |
| release (version 1.00, document version labelled "1.051") of the OpenGL |
| Shading Language. |
| |
| New Implementation Dependent State |
| |
| Added to table 6.30 (Implementation Dependent Values) |
| |
| Get Value Type Get Command Minimum Description Sec. Attrib |
| Value |
| --------- ---- ----------- ------- ----------- ---- ------ |
| EXTENSIONS S GetString - Supported extensions 6.1.11 - |
| RENDERER S GetString - Renderer string 6.1.11 - |
| SHADING_LANGUAGE_VERSION S GetString - Shading Language 6.1.11 - |
| _ARB version supported |
| VENDOR S GetString - Vendor string 6.1.11 - |
| VERSION S GetString - OpenGL version 6.1.11 - |
| supported |
| |
| Revision History |
| |
| Date: 2004/04/06 |
| Revision: 8 |
| - Corrected several typos and noted an additional reason for going to |
| minor release number 10 instead of 1 (ambiguity relative to the |
| initial "1.051" document release number). |
| |
| Date: 2004/04/06 |
| Revision: 7 |
| - Clarified that the release_number field is also vendor information, |
| and that the major.minor notation of the query and the shading |
| language specification must match in the future. Noted that not |
| supporting the query implies that version 1.00 of the shading |
| language is supported. |
| |
| Date: 2004/04/05 |
| Revision: 6 |
| - Fixed some typos. Changed errors section to require that the initial |
| version of the shading language be supported if the |
| SHADING_LANGUAGE_VERSION query fails, but the extension is |
| supported. |
| |
| Date: 2004/04/02 |
| Revision: 5 |
| - Assigned enum value to SHADING_LANGUAGE_VERSION. Corrected |
| SHADER_VERSION to SHADING_LANGUAGE_VERSION in one place previously |
| missed. |
| |
| Date: 2004/03/26 |
| Revision: 4 |
| - Changed query from SHADER_VERSION to SHADING_LANGUAGE_VERSION to |
| match extension name. Added an issue to determine exact wording of |
| the IP Status comment. |
| |
| Date: 2004/03/19 |
| Revision: 3 |
| - Resolved issues 2 and 3. Required that future shading language |
| specification version numbers match the SHADER_VERSION format. |
| Corrected omission of other GetString queries from the state tables. |
| |
| Date: 2004/03/14 |
| Revision: 2 |
| - Corrected URL to refer to opengl.org instead of 3dlabs.com. |
| - Added SHADER_VERSION string query. Defined format of the shader |
| version string and described fallback behavior for older |
| implementations of the extension. |
