NAME    [Toc]    [Back]

       glCopyTexImage2D - copy pixels into a 2D texture image

SYNOPSIS    [Toc]    [Back]

       void glCopyTexImage2D(
               GLenum target,
               GLint level,
               GLenum internalformat,
               GLint x,
               GLint y,
               GLsizei width,
               GLsizei height,
               GLint border );

PARAMETERS    [Toc]    [Back]

       Specifies  the  target  texture.  Must  be  GL_TEXTURE_2D.
       Specifies the level-of-detail number. Level 0 is the  base
       image  level.  Level  n is the nth mipmap reduction image.
       Specifies the internal  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.  Specify the window coordinates  of  the  lower
       left  corner  of  the  rectangular  region of pixels to be
       copied.  Specifies the width of the texture image. Must be
       0  or  2^n  +  2*border for some integer n.  Specifies the
       height of the texture image. Must be 0 or 2^m  +  2*border
       for  some  integer  m.  Specifies the width of the border.
       Must be either 0 or 1.

DESCRIPTION    [Toc]    [Back]

       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 (x, y) and with a width of width+2*border and a  height
       of height+2*border defines the texture array at the mipmap
       level specified by level.   internalformat  specifies  the
       internal  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  for storage in the texel
       array.

       Pixel ordering is such that lower x and y  screen  coordinates
 correspond to lower s and t texture coordinates.

       If any of the pixels within the specified rectangle of the
       current GL_READ_BUFFER are outside the  window  associated
       with  the  current  rendering  context,  then  the  values
       obtained for those pixels are undefined.

NOTES    [Toc]    [Back]

       glCopyTexImage2D is available only if the  GL  version  is
       1.1 or greater.

       Texturing has no effect in color index mode.

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

       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    [Toc]    [Back]

       GL_INVALID_ENUM is generated  if  target  is  not  GL_TEXTURE_2D.


       GL_INVALID_VALUE is generated if level is less than 0.

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


       GL_INVALID_VALUE  is  generated if width or height is less
       than 0, greater than 2+GL_MAX_TEXTURE_SIZE, or if width or
       height  cannot  be  represented as 2^k + 2*border for some
       integer k.

       GL_INVALID_VALUE is generated if border is not 0 or 1.

       GL_INVALID_VALUE is generated if internalformat 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    [Toc]    [Back]

       glGetTexImage()
       glIsEnabled() with argument GL_TEXTURE_2D

SEE ALSO    [Toc]    [Back]

       glCopyPixels(3),    glCopyTexImage1D(3),   glCopyTexSubImage1D(3), glCopyTexSubImage2D(3), glPixelStore(3),  glPixelTransfer(3),  glTexEnv(3), glTexGen(3), glTexImage1D(3),
       glTexImage2D(3),  glTexSubImage1D(3),  glTexSubImage2D(3),
       glTexParameter(3)



                                             glCopyTexImage2D(3G)