GLAPI/glTexBuffer

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glTexBuffer
Core in version 4.4
Core since version 3.0

glTexBuffer: attach the storage for a buffer object to the active buffer texture

Function Definition

 void glTexBuffer(GLenum target​, GLenum internalFormat​, GLuint buffer​);
target
Specifies the target of the operation and must be GL_TEXTURE_BUFFER​.
internalFormat
Specifies the internal format of the data in the store belonging to buffer​.
buffer
Specifies the name of the buffer object whose storage to attach to the active buffer texture.

Description

glTexBuffer attaches the storage for the buffer object named buffer​ to the active buffer texture, and specifies the internal format for the texel array found in the attached buffer object. If buffer​ is zero, any buffer object attached to the buffer texture is detached and no new buffer object is attached. If buffer​ is non-zero, it must be the name of an existing buffer object. target​ must be GL_TEXTURE_BUFFER​. internalformat​ specifies the storage format, and must be one of the following sized internal formats:

Internal Format Base Type Count Norm Components
GL_R8​ ubyte 1 YES R 0 0 1
GL_R16​ ushort 1 YES R 0 0 1
GL_R16F​ half 1 NO R 0 0 1
GL_R32F​ float 1 NO R 0 0 1
GL_R8I​ byte 1 NO R 0 0 1
GL_R16I​ short 1 NO R 0 0 1
GL_R32I​ int 1 NO R 0 0 1
GL_R8UI​ ubyte 1 NO R 0 0 1
GL_R16UI​ ushort 1 NO R 0 0 1
GL_R32UI​ uint 1 NO R 0 0 1
GL_RG8​ ubyte 2 YES R G 0 1
GL_RG16​ ushort 2 YES R G 0 1
GL_RG16F​ half 2 NO R G 0 1
GL_RG32F​ float 2 NO R G 0 1
GL_RG8I​ byte 2 NO R G 0 1
GL_RG16I​ short 2 NO R G 0 1
GL_RG32I​ int 2 NO R G 0 1
GL_RG8UI​ ubyte 2 NO R G 0 1
GL_RG16UI​ ushort 2 NO R G 0 1
GL_RG32UI​ uint 2 NO R G 0 1
GL_RGB32F​ float 3 NO R G B 1
GL_RGB32I​ int 3 NO R G B 1
GL_RGB32UI​ uint 3 NO R G B 1
GL_RGBA8​ ubyte 4 YES R G B A
GL_RGBA16​ short 4 YES R G B A
GL_RGBA16F​ half 4 NO R G B A
GL_RGBA32F​ float 4 NO R G B A
GL_RGBA8I​ byte 4 NO R G B A
GL_RGBA16I​ short 4 NO R G B A
GL_RGBA32I​ int 4 NO R G B A
GL_RGBA8UI​ ubyte 4 NO R G B A
GL_RGBA16UI​ ushort 4 NO R G B A
GL_RGBA32UI​ uint 4 NO R G B A


When a buffer object is attached to a buffer texture, the buffer object's data store is taken as the texture's texel array. The number of texels in the buffer texture's texel array is given by:

\left \lfloor \tfrac{buffer\_size}{components \times sizeof(base\_type)} \right \rfloor

where buffer_size is the size of the buffer object, in basic machine units and components and base type are the element count and base data type for elements, as specified in the table above. The number of texels in the texel array is then clamped to the implementation-dependent limit GL_MAX_TEXTURE_BUFFER_SIZE​. When a buffer texture is accessed in a shader, the results of a texel fetch are undefined if the specified texel coordinate is negative, or greater than or equal to the clamped number of texels in the texel array.

Errors

GL_INVALID_ENUM​ is generated if target​ is not GL_TEXTURE_BUFFER​.

GL_INVALID_ENUM​ is generated if internalFormat​ is not one of the accepted tokens.

GL_INVALID_OPERATION​ is generated if buffer​ is not zero or the name of an existing buffer object.

Notes

glTexBuffer is available only if the GL version is 3.1 or greater.

Associated Gets

glGet with argument GL_MAX_TEXTURE_BUFFER_SIZE​

glGet with argument GL_TEXTURE_BINDING_BUFFER​

glGetTexLevelParameter with argument GL_TEXTURE_BUFFER_DATA_STORE_BINDING​

See Also

glActiveTexture, glBindTexture, glGenBuffers, glBufferData, glTexBuffer

Copyright

Copyright © 2010-2013 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/.