1991-2006
Silicon Graphics, Inc.
glCopyTexImage2D
3G

# glCopyTexImage2D

copy pixels into a 2D texture image

## C Specification

                    void glCopyTexImage2D
                    GLenum target
                    GLint level
                    GLenum internalformat
                    GLint x
                    GLint y
                    GLsizei width
                    GLsizei height
                    GLint border

## Parameters

`target`

  Specifies the target texture. Must be `GL_TEXTURE_2D`, `GL_TEXTURE_CUBE_MAP_POSITIVE_X`, `GL_TEXTURE_CUBE_MAP_NEGATIVE_X`, `GL_TEXTURE_CUBE_MAP_POSITIVE_Y`, `GL_TEXTURE_CUBE_MAP_NEGATIVE_Y`, `GL_TEXTURE_CUBE_MAP_POSITIVE_Z`, or `GL_TEXTURE_CUBE_MAP_NEGATIVE_Z`.

`level`

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

`internalformat`

  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_COMPRESSED_ALPHA`, `GL_COMPRESSED_LUMINANCE`, `GL_COMPRESSED_LUMINANCE_ALPHA`, `GL_COMPRESSED_INTENSITY`, `GL_COMPRESSED_RGB`, `GL_COMPRESSED_RGBA`, `GL_DEPTH_COMPONENT`, `GL_DEPTH_COMPONENT16`, `GL_DEPTH_COMPONENT24`, `GL_DEPTH_COMPONENT32`, `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`, `GL_RGBA16`, `GL_SLUMINANCE`, `GL_SLUMINANCE8`, `GL_SLUMINANCE_ALPHA`, `GL_SLUMINANCE8_ALPHA8`, `GL_SRGB`, `GL_SRGB8`, `GL_SRGB_ALPHA`, or `GL_SRGB8_ALPHA8`.

`x`
`y`

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

`width`

  Specifies the width of the texture image. Must be 0 or 2 n + 2 &af; border for some integer n.

`height`

  Specifies the height of the texture image. Must be 0 or 2 m + 2 &af; border for some integer m.

`border`

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

## Description

`glCopyTexImage2D` defines a two-dimensional texture image, or cube-map 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 &af; border and a height of height + 2 &af; border defines the texture array at the mipmap level specified by `level`. `internalformat` 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.

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.

When `internalformat` is one of the sRGB types, the GL does not automatically convert the source pixels to the sRGB color space. In this case, the `glPixelMap` function can be used to accomplish the conversion.

## Notes

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

`GL_TEXTURE_CUBE_MAP_POSITIVE_X`, `GL_TEXTURE_CUBE_MAP_NEGATIVE_X`, `GL_TEXTURE_CUBE_MAP_POSITIVE_Y`, `GL_TEXTURE_CUBE_MAP_NEGATIVE_Y`, `GL_TEXTURE_CUBE_MAP_POSITIVE_Z`, `GL_TEXTURE_CUBE_MAP_NEGATIVE_Z`, or `GL_PROXY_TEXTURE_CUBE_MAP` are available only if the GL version is 1.3 or greater.

`GL_DEPTH_COMPONENT`, `GL_DEPTH_COMPONENT16`, `GL_DEPTH_COMPONENT24`, and `GL_DEPTH_COMPONENT32` are available only if the GL version is 1.4 or greater.

The `GL_SRGB`, `GL_SRGB8`, `GL_SRGB_ALPHA`, `GL_SRGB8_ALPHA8`, `GL_SLUMINANCE`, `GL_SLUMINANCE8`, `GL_SLUMINANCE_ALPHA`, and `GL_SLUMINANCE8_ALPHA8` internal formats are only available if the GL version is 2.1 or greater. See glTexImage2D for specific details about sRGB conversion.

## Errors

`GL_INVALID_ENUM` is generated if `target` is not `GL_TEXTURE_2D`, `GL_TEXTURE_CUBE_MAP_POSITIVE_X`, `GL_TEXTURE_CUBE_MAP_NEGATIVE_X`, `GL_TEXTURE_CUBE_MAP_POSITIVE_Y`, `GL_TEXTURE_CUBE_MAP_NEGATIVE_Y`, `GL_TEXTURE_CUBE_MAP_POSITIVE_Z`, or `GL_TEXTURE_CUBE_MAP_NEGATIVE_Z`.

`GL_INVALID_VALUE` is generated if `level` is less than 0.

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

`GL_INVALID_VALUE` is generated if `width` is less than 0 or greater than 2 + `GL_MAX_TEXTURE_SIZE`.

`GL_INVALID_VALUE` is generated if non-power-of-two textures are not supported and the `width` or `depth` cannot be represented as 2 k + 2 &af; 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 an accepted format.

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

`GL_INVALID_OPERATION` is generated if `internalformat` is `GL_DEPTH_COMPONENT`, `GL_DEPTH_COMPONENT16`, `GL_DEPTH_COMPONENT24`, or `GL_DEPTH_COMPONENT32` and there is no depth buffer.

## Associated Gets

glGetTexImage

glIsEnabled with argument `GL_TEXTURE_2D` or `GL_TEXTURE_CUBE_MAP`

## See Also

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

## Copyright

Copyright 1991-2006 Silicon Graphics, Inc. This document is licensed under the SGI Free Software B License. For details, see http://oss.sgi.com/projects/FreeB/.