HP Workstation zx2000 HP OpenGL Implementation Guide for HP-UX 11.X (IPF versi - Page 20

overview of OpenGL texture autogen MIPmap extension The autogen MIPmap extension introduces a side effect to the modification of the base level texture map. When enabled, any change to the base-level texture map will cause the computation of a complete MIPmap stack form for that base level. The internal formats and border widths of the derived MIPmap will match those of the base map, and the dimensions of the derived MIPmap follow the requirements set forth in OpenGL for a valid MIPmap. A simple 2 x 2 box filter is used to generate the MIPmap levels. Enumerated Types for Autogen MIPmap Extended Area Enumerated Type Description Texture Parameter GL_GENERATE_MIPMAP_EXT Default: GL_FALSE Enables autogen MIPmap To use the autogen MIPmap extension, set GL_GENERATE_MIPMAP_EXT to GL_TRUE in glTexParameter. For example, here is a code fragment that uses this extension: glTexParameter[if](GL_TEXTURE_2D,GL_GENERATE_MIPMAP_EXT, GL_TRUE); For related information on this extension, see the function: glTexParameter. X Window extensions for hp's implementation of OpenGL HP's implementation of OpenGL includes two GLX extensions that deal with extended GLX visual information that is not included in the OpenGL 1.1 Standard. These extensions are both supported by HP's implementation of the OpenGL API library, but, prior to using them, glXQueryExtensionsString should be called to verify that the extensions are supported on the target display. GLX visual information extension The GLX_EXT_visual_info extension provides additional GLX visual information and enhanced control of GLX Visual selection. The enumerated types listed below can be passed to either glXChooseVisual or glXGetConfig to specify or inquire the visual type or transparency capabilities. 1-16 OpenGL implementation guide