Difference between revisions of "GLAPI/glTexSubImage2D"

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(4.0 API.)
 
m (Math equations.)
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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 [[GLAPI/glEnable|glEnable]] and [[GLAPI/glDisable|glDisable]] with argument {{code|GL_TEXTURE_2D}}.
 
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 [[GLAPI/glEnable|glEnable]] and [[GLAPI/glDisable|glDisable]] with argument {{code|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 <!--Missing Equation-->, inclusive, and y indices ''yoffset'' and <!--Missing Equation-->, 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.
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'''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 {{code|GL_PIXEL_UNPACK_BUFFER}} target (see [[GLAPI/glBindBuffer|glBindBuffer]]) while a texture image is specified, ''data'' is treated as a byte offset into the buffer object's data store.
 
If a non-zero named buffer object is bound to the {{code|GL_PIXEL_UNPACK_BUFFER}} target (see [[GLAPI/glBindBuffer|glBindBuffer]]) while a texture image is specified, ''data'' is treated as a byte offset into the buffer object's data store.
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{{code|GL_INVALID_VALUE}} is generated if ''level'' is less than 0.
 
{{code|GL_INVALID_VALUE}} is generated if ''level'' is less than 0.
  
{{code|GL_INVALID_VALUE}} may be generated if ''level'' is greater than <!--Missing Equation-->''max'', where ''max'' is the returned value of {{code|GL_MAX_TEXTURE_SIZE}}.
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{{code|GL_INVALID_VALUE}} may be generated if ''level'' is greater than log<sub>2</sub>(''max''), where ''max'' is the returned value of {{code|GL_MAX_TEXTURE_SIZE}}.
  
{{code|GL_INVALID_VALUE}} is generated if <!--Missing Equation-->, <!--Missing Equation-->, <!--Missing Equation-->, or <!--Missing Equation-->, where <!--Missing Equation--> is the {{code|GL_TEXTURE_WIDTH}}, <!--Missing Equation--> is the {{code|GL_TEXTURE_HEIGHT}}, and <!--Missing Equation--> is the border width of the texture image being modified. Note that <!--Missing Equation--> and <!--Missing Equation--> include twice the border width.
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{{code|GL_INVALID_VALUE}} is generated if ''xoffset'' < 0, (''xoffset'' + ''width'') > ''w'', ''yoffset'' < 0, or (''yoffset'' + ''height'') > ''h'', where ''w'' is the {{code|GL_TEXTURE_WIDTH}} and ''h'' is the {{code|GL_TEXTURE_HEIGHT}}.
  
 
{{code|GL_INVALID_VALUE}} is generated if ''width'' or ''height'' is less than 0.
 
{{code|GL_INVALID_VALUE}} is generated if ''width'' or ''height'' is less than 0.

Revision as of 18:25, 31 January 2012

glTexSubImage2D
Core in version 4.5
Core since version 1.0

glTexSubImage2D: specify a two-dimensional texture subimage

Function Definition

 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​, 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 log2(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.

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/.