glGetTexLevelParameter(3G)

NAME
     glGetTexLevelParameterfv, glGetTexLevelParameteriv - return texture
     parameter values for a specific level of detail


C SPECIFICATION
     void glGetTexLevelParameterfv( GLenum target,
                                    GLint level,
                                    GLenum pname,
                                    GLfloat *params )
     void glGetTexLevelParameteriv( GLenum target,
                                    GLint level,
                                    GLenum pname,
                                    GLint *params )


PARAMETERS
     target  Specifies the symbolic name of the target texture, either
             GL_TEXTURE_1D, GL_TEXTURE_2D, GL_TEXTURE_3D, GL_PROXY_TEXTURE_1D,
             GL_PROXY_TEXTURE_2D, GL_PROXY_TEXTURE_1D_EXT,
             GL_PROXY_TEXTURE_2D_EXT, GL_PROXY_TEXTURE_3D_EXT, or
             GL_DETAIL_TEXTURE_2D_SGIS.

     level   Specifies the level-of-detail number of the desired image.  Level
             0 is the base image level.  Level n is the nth mipmap reduction
             image.

     pname   Specifies the symbolic name of a texture parameter.
             GL_TEXTURE_WIDTH, GL_TEXTURE_HEIGHT, GL_TEXTURE_DEPTH_EXT,
             GL_TEXTURE_COMPONENTS, GL_TEXTURE_INTERNAL_FORMAT,
             GL_TEXTURE_BORDER, GL_TEXTURE_RED_SIZE, GL_TEXTURE_RED_SIZE_EXT,
             GL_TEXTURE_GREEN_SIZE, GL_TEXTURE_GREEN_SIZE_EXT,
             GL_TEXTURE_BLUE_SIZE, GL_TEXTURE_BLUE_SIZE_EXT,
             GL_TEXTURE_ALPHA_SIZE, GL_TEXTURE_ALPHA_SIZE_EXT,
             GL_TEXTURE_LUMINANCE_SIZE, GL_TEXTURE_LUMINANCE_SIZE_EXT,
             GL_TEXTURE_INTENSITY_SIZE, and GL_TEXTURE_INTENSITY_SIZE_EXT are
             accepted.

     params  Returns the requested data.

DESCRIPTION
     glGetTexLevelParameter returns in params texture parameter values for a
     specific level-of-detail value, specified as level.  target defines the
     target texture, one of GL_TEXTURE_1D, GL_TEXTURE_2D, GL_TEXTURE_3D,
     GL_PROXY_TEXTURE_1D, GL_PROXY_TEXTURE_2D, GL_PROXY_TEXTURE_1D_EXT,
     GL_PROXY_TEXTURE_2D_EXT, GL_PROXY_TEXTURE_3D_EXT, or
     GL_DETAIL_TEXTURE_2D_SGIS.

     GL_MAX_TEXTURE_SIZE is not really descriptive enough.  It has to report
     the largest square texture image that can be accommodated with mipmaps
     and borders, but a long skinny texture, or a texture without mipmaps and
     borders, may easily fit in texture memory.  The proxy targets allow the
     user to more accurately query whether the GL can accommodate a texture of
     a given configuration.  If the texture cannot be accommodated, the
     texture state variables, which may be queried with
     glGetTexLevelParameter, are set to 0.  If the texture can be
     accommodated, the texture state values will be set as they would be set
     for a non-proxy target.

     pname specifies the texture parameter whose value or values will be
     returned.

     The accepted parameter names are as follows:

     GL_TEXTURE_WIDTH
               params returns a single value, the width of the texture image.
               This value includes the border of the texture image. The
               initial value is 0.

     GL_TEXTURE_HEIGHT
               params returns a single value, the height of the texture image.
               This value includes the border of the texture image. The
               initial value is 0.

     GL_TEXTURE_INTERNAL_FORMAT
               params returns a single value, the internal format of the
               texture image.

     GL_TEXTURE_DEPTH_EXT
               params returns a single value, the depth of the texture image.
               This value includes the border of the texture image.

     GL_TEXTURE_COMPONENTS
               params returns a single value, the level-of-detail's component
               as it was specified by the user.

     GL_TEXTURE_BORDER
               params returns a single value, the width in pixels of the
               border of the texture image. The initial value is 0.

     GL_TEXTURE_RED_SIZE,

     GL_TEXTURE_RED_SIZE_EXT,

     GL_TEXTURE_GREEN_SIZE,

     GL_TEXTURE_GREEN_SIZE_EXT,

     GL_TEXTURE_BLUE_SIZE,

     GL_TEXTURE_BLUE_SIZE_EXT,

     GL_TEXTURE_ALPHA_SIZE,

     GL_TEXTURE_ALPHA_SIZE_EXT,

     GL_TEXTURE_LUMINANCE_SIZE,

     GL_TEXTURE_LUMINANCE_SIZE_EXT,

     GL_TEXTURE_INTENSITY_SIZE, or

     GL_TEXTURE_INTENSITY_SIZE_EXT
               The internal storage resolution of an individual component.
               The resolution chosen by the GL will be a close match for the
               format requested by the user with the component argument of
               glTexImage1d, glTexImage2d, or glTexImage3DEXT. These values
               for pname query the format chosen by the GL, while
               GL_TEXTURE_INTERNAL_FORMAT and GL_TEXTURE_COMPONENTS are used
               to query the value requested by the user.

NOTES
     If an error is generated, no change is made to the contents of params.

     GL_TEXTURE_INTERNAL_FORMAT is only available if the GL version is 1.1 or
     greater. In version 1.0, use GL_TEXTURE_COMPONENTS instead.

     GL_PROXY_TEXTURE_1D and GL_PROXY_TEXTURE_2D are only available if the GL
     version is 1.1 or greater.

     texture3D will be present if GL_PROXY_TEXTURE_3D_EXT and
     GL_TEXTURE_3D_EXT are supported.

ERRORS
     GL_INVALID_ENUM is generated if target, pname, or params is not an
     accepted value.

     GL_INVALID_VALUE is generated if level is less than 0.

     GL_INVALID_VALUE may be generated if level is greater than log max, where
                                                                   2
     max is the returned value of GL_MAX_TEXTURE_SIZE.

     GL_INVALID_OPERATION is generated if glGetTexLevelParameter is executed
     between the execution of glBegin and the corresponding execution of
     glEnd.


SEE ALSO
     glGetTexParameter, glCopyTexImage1D, glCopyTexImage2D,
     glCopyTexSubImage1D, glCopyTexSubImage2D, glTexEnv, glTexGen,
     glTexImage1D, glTexImage2D, glTexImage3DEXT, glTexParameter,
     glTexSubImage1D, glTexSubImage2D, glGetString.