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glBindImageTexture
3G
glBindImageTexture
bind a level of a texture to an image unit
C Specification
void glBindImageTexture
GLuint unit
GLuint texture
GLint level
GLboolean layered
GLint layer
GLenum access
GLenum format
Parameters
unit
Specifies the index of the image unit to which to bind the texture
texture
Specifies the name of the texture to bind to the image unit.
level
Specifies the level of the texture that is to be bound.
layered
Specifies whether a layered texture binding is to be established.
layer
If layered is GL_FALSE, specifies the layer of texture to be bound to the image unit. Ignored otherwise.
access
Specifies a token indicating the type of access that will be performed on the image.
format
Specifies the format that the elements of the image will be treated as for the purposes of formatted stores.
Description
glBindImageTexture binds a single level of a texture to an image unit for the purpose of
reading and writing it from shaders. unit specifies the zero-based index of the image
unit to which to bind the texture level. texture specifies the name of an existing texture
object to bind to the image unit. If texture is zero, then any existing binding to
the image unit is broken. level specifies the level of the texture to bind to the image
unit.
If texture is the name of a one-, two-, or three-dimensional array texture, a cube map
or cube map array texture, or a two-dimensional multisample array texture, then it is possible to bind either
the entire array, or only a single layer of the array to the image unit. In such cases, if layered
is GL_TRUE, the entire array is attached to the image unit and layer
is ignored. However, if layered is GL_FALSE then layer
specifies the layer of the array to attach to the image unit.
access specifies the access types to be performed by shaders and may be set to
GL_READ_ONLY, GL_WRITE_ONLY, or GL_READ_WRITE
to indicate read-only, write-only or read-write access, respectively. Violation of the access type specified in access
(for example, if a shader writes to an image bound with access set to GL_READ_ONLY)
will lead to undefined results, possibly including program termination.
format specifies the format that is to be used when performing formatted stores into the
image from shaders. format must be compatible with the texture's internal format and must
be one of the formats listed in the following table.
Internal Image Formats
Image Unit Format
Format Qualifier
GL_RGBA32Frgba32f
GL_RGBA16Frgba16f
GL_RG32Frg32f
GL_RG16Frg16f
GL_R11F_G11F_B10Fr11f_g11f_b10f
GL_R32Fr32f
GL_R16Fr16f
GL_RGBA32UIrgba32ui
GL_RGBA16UIrgba16ui
GL_RGB10_A2UIrgb10_a2ui
GL_RGBA8UIrgba8ui
GL_RG32UIrg32ui
GL_RG16UIrg16ui
GL_RG8UIrg8ui
GL_R32UIr32ui
GL_R16UIr16ui
GL_R8UIr8ui
GL_RGBA32Irgba32i
GL_RGBA16Irgba16i
GL_RGBA8Irgba8i
GL_RG32Irg32i
GL_RG16Irg16i
GL_RG8Irg8i
GL_R32Ir32i
GL_R16Ir16i
GL_R8Ir8i
GL_RGBA16rgba16
GL_RGB10_A2rgb10_a2
GL_RGBA8rgba8
GL_RG16rg16
GL_RG8rg8
GL_R16r16
GL_R8r8
GL_RGBA16_SNORMrgba16_snorm
GL_RGBA8_SNORMrgba8_snorm
GL_RG16_SNORMrg16_snorm
GL_RG8_SNORMrg8_snorm
GL_R16_SNORMr16_snorm
GL_R8_SNORMr8_snorm
When a texture is bound to an image unit, the format parameter for the image
unit need not exactly match the texture internal format as long as the formats are
considered compatible as defined in the OpenGL Specification. The matching criterion used
for a given texture may be determined by calling glGetTexParameter
with value
set to GL_IMAGE_FORMAT_COMPATIBILITY_TYPE, with return values of GL_IMAGE_FORMAT_COMPATIBILITY_BY_SIZE
and GL_IMAGE_FORMAT_COMPATIBILITY_BY_CLASS, specifying matches by size and class, respectively.
Notes
The glBindImageTexture is available only if the GL version is 4.2 or greater.
Errors
GL_INVALID_VALUE is generated if unit greater than or equal to the
value of GL_MAX_IMAGE_UNITS.
GL_INVALID_VALUE is generated if texture is not the name of
an existing texture object.
GL_INVALID_VALUE is generated if level or layer
is less than zero.
GL_INVALID_ENUM is generated if access or format
is not one of the supported tokens.
Associated Gets
glGet with argument GL_IMAGE_BINDING_NAME.
glGet with argument GL_IMAGE_BINDING_LEVEL.
glGet with argument GL_IMAGE_BINDING_LAYERED.
glGet with argument GL_IMAGE_BINDING_LAYER.
glGet with argument GL_IMAGE_BINDING_ACCESS.
glGet with argument GL_IMAGE_BINDING_FORMAT.
See Also
glGenTextures,
glTexImage1D,
glTexImage2D,
glTexImage3D,
glTexStorage1D,
glTexStorage2D,
glTexStorage3D,
glBindTexture
Copyright
Copyright 2011 Khronos Group.
This material may be distributed subject to the terms and conditions set forth in
the Open Publication License, v 1.0, 8 June 1999.
http://opencontent.org/openpub/.