C SPECIFICATION

       void GLAPIENTRY glCopyTexImage2D( GLenum target,
                                         GLint leve )

PARAMETERS

       target  Specifies the target texture.  Must be GL_TEXTURE_2D.

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

       _param3 Specifies the internal format of the texture.  Must be  one  of
               the   following   symbolic   constants:   GL_ALPHA,  GL_ALPHA4,
               GL_ALPHA8, GL_ALPHA12, GL_ALPHA16, GL_LUMINANCE, GL_LUMINANCE4,
               GL_LUMINANCE8,          GL_LUMINANCE12,         GL_LUMINANCE16,
               GL_LUMINANCE_ALPHA, GL_LUMINANCE4_ALPHA4, GL_LUMINANCE6_ALPHA2,
               GL_LUMINANCE8_ALPHA8,                    GL_LUMINANCE12_ALPHA4,
               GL_LUMINANCE12_ALPHA12,  GL_LUMINANCE16_ALPHA16,  GL_INTENSITY,
               GL_INTENSITY4,  GL_INTENSITY8,  GL_INTENSITY12, GL_INTENSITY16,
               GL_RGB,  GL_R3_G3_B2,  GL_RGB4,  GL_RGB5,  GL_RGB8,   GL_RGB10,
               GL_RGB12,  GL_RGB16,  GL_RGBA,  GL_RGBA2, GL_RGBA4, GL_RGB5_A1,
               GL_RGBA8, GL_RGB10_A2, GL_RGBA12, or GL_RGBA16.

       _param4, _param5
               Specify the window coordinates of the lower left corner of  the
               rectangular region of pixels to be copied.

       _param6 Specifies  the  width  of  the  texture  image.   Must  be 0 or
               2n+2*_param8 for some integer n.

       _param7 Specifies the height of  the  texture  image.   Must  be  0  or
               2m+2*_param8 for some integer m.

       _param8 Specifies the width of the border.  Must be either 0 or 1.

DESCRIPTION

       glCopyTexImage2D  defines  a  two-dimensional texture image with pixels
       from the current GL_READ_BUFFER.

       The screen-aligned pixel rectangle with lower left corner at  (_param4,
       _param5)  and  with  a  width  of  _param6+2*_param8  and  a  height of
       _param7+2*_param8 defines the texture array at the mipmap level  speci-
       fied  by  leve.   _param3  specifies the internal format of the texture
       array.

       The pixels in the rectangle are processed exactly  as  if  glCopyPixels
       had  been  called,  but the process stops just before final conversion.
       At this point all pixel component values are clamped to the range [0,1]
       and  then converted to the texture's internal format for storage in the
       texel array.

       1, 2, 3, and 4 are not accepted values for _param3.

       An image with height or width of 0 indicates a NULL texture.

       When  the  GL_ARB_imaging  extension  is supported, the RGBA components
       read from the framebuffer may be processed  by  the  imaging  pipeline.
       See glTexImage1D for specific details.

ERRORS

       GL_INVALID_ENUM is generated if target is not GL_TEXTURE_2D.

       GL_INVALID_VALUE is generated if leve is less than 0.

       GL_INVALID_VALUE  may  be  generated  if  leve is greater than log2max,
       where max is the returned value of GL_MAX_TEXTURE_SIZE.

       GL_INVALID_VALUE is generated if _param6 or _param7  is  less  than  0,
       greater  than 2+GL_MAX_TEXTURE_SIZE, or if _param6 or _param7 cannot be
       represented as 2k+2*_param8 for some integer k.

       GL_INVALID_VALUE is generated if _param8 is not 0 or 1.

       GL_INVALID_VALUE is generated if _param3 is not one  of  the  allowable
       values.

       GL_INVALID_OPERATION  is  generated  if  glCopyTexImage2D  is  executed
       between the execution of glBegin and  the  corresponding  execution  of
       glEnd.

ASSOCIATED GETS

       glGetTexImage
       glIsEnabled with argument GL_TEXTURE_2D

SEE ALSO

       glCopyPixels,           glCopyTexImage1D,          glCopyTexSubImage1D,
       glCopyTexSubImage2D, glPixelStore, glPixelTransfer, glTexEnv, glTexGen,
       glTexImage1D, glTexImage2D, glTexSubImage1D, glTexSubImage2D,
       glTexParameter





                                                          GLCOPYTEXIMAGE2D(3G)