NAME¶
glTexSubImage2D - specify a two-dimensional texture subimage
C SPECIFICATION¶
void
glTexSubImage2D(GLenum target,
GLint level, GLint xoffset,
GLint yoffset, GLsizei width,
GLsizei height, GLenum format,
GLenum type,
const GLvoid * data);
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.
xoffset
Specifies a texel offset in the x direction
within the texture array.
yoffset
Specifies a texel offset in the y direction
within the texture array.
width
Specifies the width of the texture
subimage.
height
Specifies the height of the texture
subimage.
format
Specifies the format of the pixel data. The
following symbolic values are accepted: GL_RED, GL_RG,
GL_RGB, GL_BGR, GL_RGBA, and GL_BGRA.
type
Specifies the data type of the pixel data. The
following symbolic values are accepted: GL_UNSIGNED_BYTE,
GL_BYTE, GL_UNSIGNED_SHORT, GL_SHORT,
GL_UNSIGNED_INT, GL_INT, GL_FLOAT,
GL_UNSIGNED_BYTE_3_3_2, GL_UNSIGNED_BYTE_2_3_3_REV,
GL_UNSIGNED_SHORT_5_6_5, GL_UNSIGNED_SHORT_5_6_5_REV,
GL_UNSIGNED_SHORT_4_4_4_4, GL_UNSIGNED_SHORT_4_4_4_4_REV,
GL_UNSIGNED_SHORT_5_5_5_1, GL_UNSIGNED_SHORT_1_5_5_5_REV,
GL_UNSIGNED_INT_8_8_8_8, GL_UNSIGNED_INT_8_8_8_8_REV,
GL_UNSIGNED_INT_10_10_10_2, and
GL_UNSIGNED_INT_2_10_10_10_REV.
data
Specifies a pointer to the image data in
memory.
DESCRIPTION¶
Texturing maps a portion of a specified texture image onto each graphical
primitive for which texturing is enabled. To enable and disable
two-dimensional texturing, call
glEnable() and
glDisable() with
argument
GL_TEXTURE_2D.
glTexSubImage2D redefines a contiguous subregion of an existing
two-dimensional texture image. The texels referenced by
data replace
the portion of the existing texture array with x indices
xoffset and
xoffset + width - 1, inclusive, and y indices
yoffset and yoffset +
height - 1, inclusive. This region may not include any texels outside the
range of the texture array as it was originally specified. It is not an error
to specify a subtexture with zero width or height, but such a specification
has no effect.
If a non-zero named buffer object is bound to the
GL_PIXEL_UNPACK_BUFFER
target (see
glBindBuffer()) while a texture image is specified,
data is treated as a byte offset into the buffer object's data store.
NOTES¶
glPixelStore() modes affect texture images.
glTexSubImage2D specifies a two-dimensional subtexture for the current
texture unit, specified with
glActiveTexture().
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_ENUM is generated if
format is not an accepted format
constant.
GL_INVALID_ENUM is generated if
type is not a type constant.
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 xoffset < - b, xoffset + width > w
- b, yoffset < - b, or yoffset + height > h - b, where w is the
GL_TEXTURE_WIDTH, h is the
GL_TEXTURE_HEIGHT, and b is the
border width of the texture image being modified. Note that w and h include
twice the border width.
GL_INVALID_VALUE is generated if
width or
height is less
than 0.
GL_INVALID_OPERATION is generated if the texture array has not been
defined by a previous
glTexImage2D() operation.
GL_INVALID_OPERATION is generated if
type is one of
GL_UNSIGNED_BYTE_3_3_2,
GL_UNSIGNED_BYTE_2_3_3_REV,
GL_UNSIGNED_SHORT_5_6_5, or
GL_UNSIGNED_SHORT_5_6_5_REV and
format is not
GL_RGB.
GL_INVALID_OPERATION is generated if
type is one of
GL_UNSIGNED_SHORT_4_4_4_4,
GL_UNSIGNED_SHORT_4_4_4_4_REV,
GL_UNSIGNED_SHORT_5_5_5_1,
GL_UNSIGNED_SHORT_1_5_5_5_REV,
GL_UNSIGNED_INT_8_8_8_8,
GL_UNSIGNED_INT_8_8_8_8_REV,
GL_UNSIGNED_INT_10_10_10_2, or
GL_UNSIGNED_INT_2_10_10_10_REV
and
format is neither
GL_RGBA nor
GL_BGRA.
GL_INVALID_OPERATION is generated if a non-zero buffer object name is
bound to the
GL_PIXEL_UNPACK_BUFFER target and the buffer object's data
store is currently mapped.
GL_INVALID_OPERATION is generated if a non-zero buffer object name is
bound to the
GL_PIXEL_UNPACK_BUFFER target and the data would be
unpacked from the buffer object such that the memory reads required would
exceed the data store size.
GL_INVALID_OPERATION is generated if a non-zero buffer object name is
bound to the
GL_PIXEL_UNPACK_BUFFER target and
data is not
evenly divisible into the number of bytes needed to store in memory a datum
indicated by
type.
ASSOCIATED GETS¶
glGetTexImage()
glGet() with argument
GL_PIXEL_UNPACK_BUFFER_BINDING
SEE ALSO¶
glActiveTexture(),
glCopyTexImage1D(),
glCopyTexImage2D(),
glCopyTexSubImage1D(),
glCopyTexSubImage2D(),
glCopyTexSubImage3D(),
glPixelStore(),
glTexImage1D(),
glTexImage2D(),
glTexImage3D(),
glTexSubImage1D(),
glTexSubImage3D(),
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/.