glGenerateMipmap — generate a complete set of mipmaps for a texture object
void glGenerateMipmap( | GLenum target); |
targetSpecifies the texture target of the active texture unit to which the texture object
is bound whose mipmaps will be generated. Must be one of the following
symbolic constants: GL_TEXTURE_2D or
GL_TEXTURE_CUBE_MAP.
glGenerateMipmap computes a complete set
of mipmap arrays derived from the zero level array. Array levels up to and
including the 1x1 dimension texture image are replaced with the derived arrays,
regardless of previous contents. The zero level texture image is left unchanged.
The internal formats of the derived mipmap arrays all match those of the zero level texture image. The dimensions of the derived arrays are computed by halving the width and height of the zero level texture image, then in turn halving the dimensions of each array level until the 1x1 dimension texture image is reached.
The contents of the derived arrays are computed by repeated filtered reduction of the zero level array. No particular filter algorithm is required, though a box filter is recommended. glHint may be called to express a preference for speed or quality of filtering.
GL_INVALID_ENUM is generated if
target is not GL_TEXTURE_2D or
GL_TEXTURE_CUBE_MAP.
GL_INVALID_OPERATION is generated if
the texture bound to target is a cube map, but its
six faces do not share indentical widths, heights, formats, and types.
GL_INVALID_OPERATION is generated if
either the width or height of the zero level array is not a power of two.
GL_INVALID_OPERATION is generated if
the zero level array is stored in a compressed internal format.
Copyright © 2008 Khronos Group. This material may be distributed subject to the terms and conditions set forth in the Open Publication License, v 1.0, 8 June 1999. http://opencontent.org/openpub/.