OpenGL(R) 1.1 Release for Windows(R) 95 --------------------------------------- 1. OpenGL Functionality Notes 2. Redistributable components for Windows 95 1. Functionality Notes ----------------------- The OpenGL API is supported on a variety of graphics hardware; the software in this release provides support for graphics hardware including basic emulation on any video adapter that is supported with the operating system, and accelerated graphics hardware that is supported by an OpenGL mini-client driver (MCD) or an OpenGL installable client driver (ICD). This release of OpenGL will run on all supported hardware under Windows 95, including VGA and Super VGA 16 color mode displays. The OpenGL runtime libraries for Windows 95 are not bundled with the Windows 95 operating system currently, but application developers may freely redistribute from this SDK along with their applications to other Windows 95 systems. In addition, the runtime libraries have been bundled with the Windows 95 operating system in the OEM system release 2, so OEM Windows 95 systems shipping later in 1996 will begin appearing with the OpenGL runtime libraries included. To achieve good shaded rendering with OpenGL applications, you should use a color graphics mode with 256 or more colors. Reasonable shading is possible for most OpenGL applications with 256 colors. The Windows NT 4.0 and Windows 95 releases of OpenGL includes new functionality and performance enhancements. These include: 1) A complete implementation of OpenGL 1.1. OpenGL 1.1 contains several functions, including vertex array, polygon offset, logic ops, and several new functions for handling textures. The vertex array and texture calls are particularly significant, as they may enable order of magnitude performance improvements in some applications. 2) Overlay planes extensions. These Microsoft OpenGL extensions permit applications to manage and render into overlay planes where supported in the graphics hardware. This permits applications to bring up dialog boxes and other UI features without overwriting 3D renderings. 3) Extended metafile support. Applications may encapsulate OpenGL calls and data in GDI extended metafiles. This, together with NT 4.0 print spooler enhancements for remote metafile rendering, makes it possible to print OpenGL graphics at high resolution on the print server. This feature is limited to the Windows NT release. 4) Microsoft extensions. The Microsoft OpenGL implementation also supports these performance extensions: GL_WIN_swap_hint, GL_EXT_bgra, and GL_EXT_paletted_texture. They improve the performance of some applications significantly. 5) Performance. The software renderer has been tuned for this release. Performance tuning has been carried out for the front end of the OpenGL pipeline as well as for rendering particular primitives, especially anti-aliased lines and texturing. Software rendering is generally 2-4x faster. 6) OpenGL hardware acceleration. This release of OpenGL supports a simpler mini-client driver (MCD) model to accelerate 3D graphics operations. In particular, Windows NT 4.0 includes a Matrox Millennium mini-client driver that accelerates OpenGL functions. A corresponding driver for Windows 95 is expected to be available later this year. 2. Redistributable components for Windows 95 -------------------------------------------- The OpenGL redistributable components for Windows 95 are in the DLL directory. It contains the runtime dynamic-link libraries for OpenGL and GLU. We recommend either of two methods for redistributing these libraries with your application on Windows 95 (for Windows NT, the libraries are bundled with the operating system and should not be redistributed): 1) In your setup program, install these libraries in the application directory along with your application. This gives you greater control over the version of OpenGL that your application will link to (an issue if other applications install other versions of the library), but also gives you greater responsibility for updating your customers' libraries if and when that is required to address defects, add functionality, improve performance, etc. 2) In your setup program, install these libraries in the windows system directory. If you do this, you should use the Win32 setup API call VerInstallFile to help prevent installing an older version of the libraries over another application's installation of a more recent version of the libraries. OpenGL is a registered trademark of Silicon Graphics, Inc. Windows is a registered trademark of Microsoft Corporation.