GlTexSubImage2D

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_glTexSubImage2D: specify a two-dimensional texture subimage


Syntax

 SUB _glTexSubImage2D (BYVAL target AS _UNSIGNED LONG, BYVAL level AS LONG, BYVAL xoffset AS LONG, BYVAL yoffset AS LONG, BYVAL width AS LONG, BYVAL height AS LONG, BYVAL format AS _UNSIGNED LONG, BYVAL type AS _UNSIGNED LONG, pixels AS _OFFSET)
 void _glTexSubImage2D(GLenum target, GLint level, GLint xoffset, GLint yoffset, GLsizei width, GLsizei height, GLenum format, GLenum type, const GLvoid * data);


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, _GL_TEXTURE_CUBE_MAP_NEGATIVE_Z, or _GL_TEXTURE_1D_ARRAY.
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.

Template:Glapi pixeltransferupparams


Description

Texturing maps a portion of a specified texture image onto each graphical primitive for which texturing is enabled.

_glTexSubImage2D redefines a contiguous subregion of an existing two-dimensional or one-dimensional array 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, _GL_TEXTURE_CUBE_MAP_NEGATIVE_Z, or _GL_TEXTURE_1D_ARRAY.

_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<sub>2</sub>(max), where max is the returned value of _GL_MAX_TEXTURE_SIZE.

_GL_INVALID_VALUE is generated if xoffset < 0, (xoffset + width) > w, yoffset < 0, or (yoffset + height) > h, where w is the _GL_TEXTURE_WIDTH and h is the _GL_TEXTURE_HEIGHT.

_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.


Use With:

_glGetTexImage

_glGet with argument _GL_PIXEL_UNPACK_BUFFER_BINDING


See also

SUB _GL _glActiveTexture, _glBindTexture, _glTexSubImage1D, _glTexSubImage3D, _glCopyTexImage2D, _glTexImage2D, _glTexStorage2D, _glTextureView, _glPixelStore


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/.



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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/.