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_COMPRESSED_RED,
GL_COMPRESSED_RG,
GL_COMPRESSED_RGB,
GL_COMPRESSED_RGBA.
GL_COMPRESSED_SRGB,
GL_COMPRESSED_SRGB_ALPHA.
GL_DEPTH_COMPONENT,
GL_DEPTH_COMPONENT16,
GL_DEPTH_COMPONENT24,
GL_DEPTH_COMPONENT32,
GL_RED,
GL_RG,
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_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
⁡
border
for some integer
n.
height
Specifies the height of the texture image.
Must be 0 or
2
m
+
2
⁡
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
⁡
border
and a height of
height
+
2
⁡
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
glReadPixels 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
1, 2, 3, and 4 are not accepted values for internalformat.
An image with height or width of 0 indicates a NULL texture.
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
⁢
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
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
⁡
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 internalformat is
GL_DEPTH_COMPONENT, GL_DEPTH_COMPONENT16,
GL_DEPTH_COMPONENT24, or GL_DEPTH_COMPONENT32 and there is no depth
buffer.
Associated Gets
glGetTexImage
See Also
glCopyTexImage1D,
glCopyTexSubImage1D,
glCopyTexSubImage2D,
glPixelStore,
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/.