2010 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_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/.