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GLGETTEXLEVELPARAMETER(3G)                                                        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, or GL_PROXY_TEXTURE_3D.

       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,    GL_TEXTURE_INTERNAL_FORMAT,    GL_TEXTURE_BORDER,   GL_TEXTURE_RED_SIZE,
               GL_TEXTURE_GREEN_SIZE,              GL_TEXTURE_BLUE_SIZE,              GL_TEXTURE_ALPHA_SIZE,
               GL_TEXTURE_LUMINANCE_SIZE, and GL_TEXTURE_INTENSITY_SIZE 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, either  GL_TEXTURE_1D,  GL_TEXTURE_2D,
       GL_TEXTURE_3D, GL_PROXY_TEXTURE_1D, GL_PROXY_TEXTURE_2D, or GL_PROXY_TEXTURE_3D.

       GL_MAX_TEXTURE_SIZE,  and GL_MAX_3D_TEXTURE_SIZE are 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 tar-gets targets
       gets allow the user to more accurately query whether the GL can accommodate a texture of a given con-figuration. configuration.
       figuration.  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_DEPTH
                 params  returns  a  single  value, the depth 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  of the texture image.

       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_GREEN_SIZE,

       GL_TEXTURE_BLUE_SIZE,

       GL_TEXTURE_ALPHA_SIZE,

       GL_TEXTURE_LUMINANCE_SIZE,

       GL_TEXTURE_INTENSITY_SIZE
                 The  internal  storage resolution of an individual component.  The resolution chosen by the
                 GL will be a close match for the resolution requested by the user with the component  argu-ment argument
                 ment  of  glTexImage1D, glTexImage2D, glTexImage3D, glCopyTexImage1D, and glCopyTexImage2D.
                 The initial value is 0.

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

       GL_TEXTURE_INTERNAL_FORMAT is available only 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 available only if the GL version is 1.1 or greater.

       GL_TEXTURE_3D,  GL_PROXY_TEXTURE_3D, and GL_TEXTURE_DEPTH are available only if the GL version is 1.2
       or greater.

       When the GL_ARB_multitexture extension is supported, glGetTexLevelParameter returns the texture level
       parameters for the active texture unit.

ERRORS
       GL_INVALID_ENUM is generated if target or pname 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 log2(max), where 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
       glActiveTextureARB(3G),   glGetTexParameter(3G),   glCopyTexImage1D(3G),  glCopyTexImage2D(3G),  glCopyTexSubImage1D(3G),
       glCopyTexSubImage2D(3G),   glCopyTexSubImage3D(3G),   glTexEnv(3G),   glTexGen(3G),    glTexImage1D(3G),    glTexImage2D(3G),
       glTexImage3D(3G), glTexSubImage1D(3G), glTexSubImage2D(3G), glTexSubImage3D(3G), glTexParameter(3G)




                                                                                  GLGETTEXLEVELPARAMETER(3G)