2011-2013
Khronos Group
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_RGBA32F
rgba32f
GL_RGBA16F
rgba16f
GL_RG32F
rg32f
GL_RG16F
rg16f
GL_R11F_G11F_B10F
r11f_g11f_b10f
GL_R32F
r32f
GL_R16F
r16f
GL_RGBA32UI
rgba32ui
GL_RGBA16UI
rgba16ui
GL_RGB10_A2UI
rgb10_a2ui
GL_RGBA8UI
rgba8ui
GL_RG32UI
rg32ui
GL_RG16UI
rg16ui
GL_RG8UI
rg8ui
GL_R32UI
r32ui
GL_R16UI
r16ui
GL_R8UI
r8ui
GL_RGBA32I
rgba32i
GL_RGBA16I
rgba16i
GL_RGBA8I
rgba8i
GL_RG32I
rg32i
GL_RG16I
rg16i
GL_RG8I
rg8i
GL_R32I
r32i
GL_R16I
r16i
GL_R8I
r8i
GL_RGBA16
rgba16
GL_RGB10_A2
rgb10_a2
GL_RGBA8
rgba8
GL_RG16
rg16
GL_RG8
rg8
GL_R16
r16
GL_R8
r8
GL_RGBA16_SNORM
rgba16_snorm
GL_RGBA8_SNORM
rgba8_snorm
GL_RG16_SNORM
rg16_snorm
GL_RG8_SNORM
rg8_snorm
GL_R16_SNORM
r16_snorm
GL_R8_SNORM
r8_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 2011-2013 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/.