OpenGL^® for Windows^® from Silicon Graphics^®
Release Notes for Manufacturing Release 2

These release notes describe the second manufacturing release of OpenGL for Windows by Silicon Graphics. The following sections are included:

1. Legal Notices
2. Installing OpenGL
3. Supported Hardware Configurations
4. How to Use Silicon Graphics' OpenGL library
5. Where to Find Additional Demos and Utilities
6. Known Bugs and Limitations
7. Reporting Bugs

1. Legal Notices

Software License Agreement

1. Grant Of Limited License; Software Use Restrictions. In consideration for your acceptance of the terms and conditions of this Agreement, SGI will grant to you a personal, non-transferable and non-exclusive right to use and execute the Software on a personal computer (a “"PC"”), without right to sublicense or distribute the Software (except as provided in Section 3 below). You agree that you will not modify, reverse engineer, decompile or disassemble any portion of the Software.

2. Duplication Restrictions. In order to effect your license rights hereunder, you may install the Software by duplicating it onto the hard disk drive or into the CPU memory of a PC for use thereon, and you may make full or partial copies of the Software, but only as necessary for backup or archival purposes or for purposes of distribution pursuant to Section 3 below. You agree that (i) your use and possession of such copies shall be solely under the terms and conditions of this Agreement, and (ii) you shall place the same proprietary and copyright notices and legends on all such copies as included by SGI on any media containing an authorized copy of the Software originally provided by SGI.

3. Distribution of the Software to Others. You may duplicate and distribute copies of the Software to others, or allow copies of the Software to be made by someone else, provided that all such copies include a copy of this License Agreement.

4. Ownership of Software. You agree and acknowledge that SGI transfers no ownership interest in the Software, in the intellectual property in any Software or in any Software copy, to you under this Agreement or otherwise, and that SGI and its licensors reserve all rights not expressly granted to you hereunder.

5. Transfer Restrictions. This license is personal to you. Except as expressly provided in Section 3 above, you may not transfer the Software and/or assign this License to any third party. If you attempt to transfer or assign this License, such transfer or assignment will be void and without effect.

6. Export Restrictions. You may not export or reexport any Software or other technology received under this Agreement except in full compliance with all United States and other applicable laws and regulations. In particular, none of such Software or technology may be exported or reexported into (or to a national or resident of) any country to which the U.S. embargoes goods, or to anyone on the U.S. Treasury Department's list of Specially Designated Nationals or the U.S. Commerce Department's Table of Denial Orders.

7. Term; Termination. The term of this Agreement shall commence when you electronically download or receive (if SGI delivers the Software to you by email or alternative means) and shall continue thereafter. If you fail to fulfill any of your material obligations under this Agreement, SGI and/or its licensors may pursue all available legal remedies to enforce this Agreement, and SGI may, at any time after your default of this Agreement, terminate this Agreement and all licenses and rights granted to you under this Agreement. You agree that SGI’'s licensors referenced in the Software are third-party beneficiaries of this Agreement, and may enforce this Agreement as it relates to their intellectual property. You further agree that, if SGI terminates this Agreement for your default, you will, within thirty (30) days after any such termination, deliver to SGI or render unusable all Software originally provided to you hereunder and any copies thereof embodied in any medium.

8. Governing Law. This Agreement shall be governed by and interpreted in accordance with the laws of the State of California, excluding its choice of law rules.

U. S. GOVERNMENT USERS. If the Software is acquired by or on behalf of an entity of government of the United States of America, the following provision applies: U. S. GOVERNMENT RESTRICTED RIGHTS LEGEND Use, duplication or disclosure of Software by the Government is subject to restrictions as set forth in FAR 52.227-19(c)(2) or subparagraph (c)(1)(ii) of the Rights in Technical Data and Computer Software clause at DFARS 252.227-7013 and/or in similar or successor clauses in the FAR, or the DOD or NASA FAR Supplement. Unpublished- rights reserved under the Copyright Laws of the United States. Contractor/manufacturer is SILICON GRAPHICS, INC., 2011 N. Shoreline Blvd., Mountain View, CA 94039- 7311.

9. Disclaimer Of Software Warranty. SGI PROVIDES THE SOFTWARE TO YOU “"AS IS"” AND WITHOUT WARRANTY OF ANY KIND, EXPRESS, STATUTORY, IMPLIED OR OTHERWISE, INCLUDING WITHOUT LIMITATION ANY WARRANTY OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE OR INFRINGEMENT. NO ORAL OR WRITTEN INFORMATION OR ADVICE GIVEN TO YOU BY ANY SGI EMPLOYEE, REPRESENTATIVE OR DISTRIBUTOR WILL CREATE A WARRANTY FOR THE SOFTWARE, AND YOU MAY NOT RELY ON ANY SUCH INFORMATION OR ADVICE.

10. Limitation Of Liability. IN NO EVENT SHALL SGI OR IT LICENSORS BE LIABLE TO YOU FOR ANY SPECIAL, CONSEQUENTIAL, INCIDENTAL OR INDIRECT DAMAGES OF ANY KIND (INCLUDING WITHOUT LIMITATION THE COST OF COVER, DAMAGES ARISING FROM LOSS OF DATA, USE, PROFITS OR GOODWILL, OR PROPERTY DAMAGE), WHETHER OR NOT SGI HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH LOSS, HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY ARISING OUT OF THIS AGREEMENT. THESE LIMITATIONS SHALL APPLY NOTWITHSTANDING THE FAILURE OF ESSENTIAL PURPOSE OF ANY LIMITED REMEDY. 05/31/96

2. Installing OpenGL

You can download OPENGL2.EXE from the OpenGL for Windows web site. After you have obtained OPENGL2.EXE, copy it into a temporary directory, then run it. This will create the following directories under C:\OGLSDK (unless you asked setup to install OpenGL for Windows under a different top level directory):

• DEMOS\
  This contains executables for a few OpenGL demo programs.
• DOC\
  This contains a copy of the the user guide, and documentation on the OpenGL for Windows extensions. To look at the documentation, use your favorite html browser and open up the file INDEX.HTML.
• EXAMPLES\
  This contains OpenGL sample source code. You will find the following programs:
  MISC\
  
  • CUBE.C - A simple example of how to write an OpenGL program with Windows. This program is described in the User Guide .
  • INDEXFNC.C - Draws a triangle, a line, and an image using the SGI_index_func extension.
  • INDEXMAT.C - Draws two lit objects with color index materials using the SGI_index_material extension.
  • INDEXTEX.C - Draws a textured object in color index mode using the SGI_index_texture extension.
  • SIMPLECI.C - A simple color index program.
  • TEXENV.C - Shows how to use texture internal formats and all the texture environments.
  • TORUS.C - Renders a torus in rgb mode. It uses the vertex culling extension (SGI_cull_vertex) and the compile vertex array extension (SGI_compiled_vertex_array) to define the torus.
  • VCULL.C - Another example of using the SGI_cull_vertex and SGI_compiled_vertex_array extensions.
  • WGLINFO.C - Displays information about supported pixel formats.
  • FULLSCREEN\
    An example of a full screen OpenGL application which can change video display modes. This example requires the use of the GLUT library.
  • SPHERE\
    A simple throughput benchmark; it renders a spinning lit sphere.
  • RB\
    A rasterization benchmark; it renders screen coordinate tristrips.
• INCLUDE\GL\
  This contains GL.H and GLU.H.
• LIB\
  This contains the OpenGL and GLU link libraries for Microsoft Visual C++ (ie., OPENGL.LIB and GLU.LIB).
• BCLIB\
  This contains the OpenGL and GLU link libraries for Borland C++ version 4.52.

The OpenGL Dynamic Link Libraries OPENGL.DLL and GLU.DLL will be installed in the windows system directory.

3. Supported Hardware Configurations

OpenGL for Windows has been successfully tested on PC's with Pentium, Pentium Pro, Pentium II, AMD K6 and Cyrix 6x86 processors that are running the Windows 95 or Windows NT 4.0 operating systems. It is recommended (but not required) that you have at least 16MB of RAM.

4. How to Use OpenGL for Windows

To use SGI's OpenGL for Windows you must link with OPENGL.LIB and GLU.LIB instead of OPENGL32.LIB and GLU32.LIB respectively. Also make sure that OPENGL.LIB and GLU.LIB precede GDI32.lib in the library list. Since SGI's OpenGL for Windows library overloads the ChoosePixelFormat() function in GDI you need to make sure that you link the libraries in the right order so you don't pick up the wrong version of ChoosePixelFormat().

You should also set your include path so that SGI's header files have precedence over Microsoft's. This is required if you wish to use any of the extensions provided in SGI's OpenGL library for Windows.

If an application linked to SGI's OpenGL library is running on a system with hardware acceleration (ie., a system that has an OpenGL ICD or MCD installed), the library will automatically fall back to using Microsoft's OpenGL implementation. You can change this behaviour by creating a value in the Registry as a DWORD:

HKEY_LOCAL_MACHINE\Software\Silicon Graphics\OpenGL\OverrideDispatch

• 0: default (use OpenGL for Windows unless hardware accelerated)
• 1: force use of OpenGL for Windows
• 2: force use of Microsoft's OpenGL Implementation

You can find out whether you are using SGI's OpenGL library or Microsoft's OpenGL library, by running WGLINFO.EXE. Source for WGLINFO.EXE can be found in the EXAMPLES\MISC directory.

5. Where to Find Additional Demos and Utilities

GLUT
You can download the glut source code along with more example programs written with glut from Mark Kilgard's GLUT Page or Nate Robin's OpenGL Page.

Example Programs
If you want additional example code, you can ftp the SampleGL Example Programs.

6. Changes in Release 2

The following problems have been fixed:

• OpenGL could crash during initialization when run on a system with an Intel 486 or Cyrix 6x86 processor because of the sequence of instructions used to identify the CPU.
• There could be unexpected rendering artifacts resulting from overflow of the color interpolants when dithering was enabled in a 16-bit display mode.
• Texels could be selected from the wrong mipmap level due to a floating point underflow when computing the level of detail during perspective correct texture mapping.
• The PFD_SWAP_COPY bit was not being set in the dwFlags field of double buffered pixel formats.
• OpenGL could crash following a window resize.
• There was an occasional memory leak when deleting texture objects.
• The space character was displayed incorrectly for some fonts created by calling wglUseFontBitmaps().
• COLOR_MATERIAL did not always work correctly when used with vertex arrays.
• OpenGL could crash when redirecting to OpenGL32.dll
• The OpenGL DLL did not have a VS_VERSION_INFO resource.
• When used in conjunction with SciTech Software's MGL, problems relating to back buffer initialization and resizing have been fixed.

The following optimizations have been made:

• Lighting for directional light sources and state changes affecting lighting have been made faster.
• Certain internal caching algorithms have been tuned, providing better geometry pipeline performance for some programs. In particular, the overhead for glBegin()/glEnd() and the overhead for state changes was reduced.

7. Known Bugs and Limitations

• Outline fonts drawn via wglUseOutlineFonts() with extrusion produce correct geometry but the edge normals are incorrect.

• Color index rendering to a windows only works in 8 bit framebuffer modes. Color index rendering to an 8-bit DIB works correctly regardless of the framebuffer setting.

• Rendering to the front buffer with an 8-bit pixel format (i.e., 8 bit color index rendering or 8 bit RGB rendering) requires the identity palette.

• There is no support for destination alpha.

• Polygon offset does not work when the polygon mode is GL_POINT or GL_LINE. (i.e., polygon offset only works for polygon mode GL_FILL.)

• The anti-aliased point and anti-aliased polygon conformance tests do not pass.

• OpenGL for Windows has only been tested on the following graphics chip sets:
  • ATI Rage II
  • IGS 1682
  • Matrox Mystique and Millenium
  • S3 968 and Virge/VX
  • 3DLabs Permediat NT and Permedia II
  • Rendition Verite

• The following extensions are implemented in SGI's OpenGL library for Windows:
  • GL_SGI_cull_vertex
  • GL_SGI_compiled_vertex_array
  • GL_SGI_index_array_formats
  • GL_SGI_index_func
  • GL_SGI_index_material
  • GL_SGI_index_texture
  The interface to these extensions may change after they have been reviewed by the OpenGL ARB. Also, some of them may become EXT extensions (i.e., use EXT as the suffix instead of SGI) after they have been reviewed.

• The following paths are not optimized:
  • polygon offset (i.e., glEnable(GL_POLYGON_OFFSET_FILL))
  • drawbuffer front and back (i.e., glDrawBuffer(GL_FRONT_AND_BACK))
  • blending functions other than GL_ZERO, GL_ONE, GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA (see glBlendFunc()), except on systems with MMX extensions in 16-bit framebuffers.
  • texture borders
  • texture filters other than GL_NEAREST (see glTexParameter())
  • stencil, stipple, and alpha test

8. Reporting Bugs

OpenGL for Windows is free, unsupported software. However, if you find bugs, or have other comments about the software, you can report them to the OpenGL for Windows development team by using the feedback form on the SGI OpenGL for Windows web site or by sending mail to win-opengl@sgi.com.

We welcome feedback and comments at win-opengl@sgi.com.

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