GLAPI/glTextureView

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glTextureView
Core in version 4.4
Core since version 4.3
Core ARB extension ARB_texture_view

glTextureView: initialize a texture as a data alias of another texture's data store

Function Definition

 void glTextureView(GLuint texture​, GLenum target​, GLuint origtexture​, GLenum internalformat​, GLuint minlevel​, GLuint numlevels​, GLuint minlayer​, GLuint numlayers​);
texture
Specifies the texture object to be initialized as a view.
target
Specifies the target to be used for the newly initialized texture.
origtexture
Specifies the name of a texture object of which to make a view.
internalFormat
Specifies the internal format for the newly created view.
minlevel
Specifies lowest level of detail of the view.
numlevels
Specifies the number of levels of detail to include in the view.
minlayer
Specifies the index of the first layer to include in the view.
numlayers
Specifies the number of layers to include in the view.

Description

glTextureView initializes a texture object as an alias, or view of another texture object, sharing some or all of the parent texture's data store with the initialized texture. texture​ specifies a name previously reserved by a successful call to glGenTextures but that has not yet been bound or given a target. target​ specifies the target for the newly initialized texture and must be compatible with the target of the parent texture, given in origtexture​ as specified in the following table:

Original Target Compatible New Targets
GL_TEXTURE_1D​ GL_TEXTURE_1D​, GL_TEXTURE_1D_ARRAY​
GL_TEXTURE_2D​ GL_TEXTURE_2D​, GL_TEXTURE_2D_ARRAY​
GL_TEXTURE_3D​ GL_TEXTURE_3D​
GL_TEXTURE_CUBE_MAP​ GL_TEXTURE_CUBE_MAP​, GL_TEXTURE_2D​, GL_TEXTURE_2D_ARRAY​, GL_TEXTUER_CUBE_MAP_ARRAY​
GL_TEXTURE_RECTANGLE​ GL_TEXTURE_RECTANGLE​
GL_TEXTURE_BUFFER​ none. Cannot be used with this function.
GL_TEXTURE_1D_ARRAY​ GL_TEXTURE_1D​, GL_TEXTURE_1D_ARRAY​
GL_TEXTURE_2D_ARRAY​ GL_TEXTURE_2D​, GL_TEXTURE_CUBE_MAP​, GL_TEXTURE_2D_ARRAY​, GL_TEXTUER_CUBE_MAP_ARRAY​
GL_TEXTURE_CUBE_MAP_ARRAY​ GL_TEXTURE_CUBE_MAP​, GL_TEXTURE_2D​, GL_TEXTURE_2D_ARRAY​, GL_TEXTUER_CUBE_MAP_ARRAY​
GL_TEXTURE_2D_MULTISAMPLE​ GL_TEXTURE_2D_MULTISAMPLE​, GL_TEXTURE_MULTISAMPLE_ARRAY​
GL_TEXTURE_2D_MULTISAMPLE_ARRAY​ GL_TEXTURE_2D_MULTISAMPLE​, GL_TEXTURE_MULTISAMPLE_ARRAY​


The value of GL_TEXTURE_IMMUTABLE_FORMAT​ for origtexture​ must be GL_TRUE​. After initialization, texture​ inherits the data store of the parent texture, origtexture​ and is usable as a normal texture object with target target​. Data in the shared store is reinterpreted with the new internal format specified by internalformat​. internalformat​ must be compatible with the internal format of the parent texture as specified in the following table:

Class Internal Formats
128-bit GL_RGBA32F​, GL_RGBA32UI​, GL_RGBA32I​
96-bit GL_RGB32F​, GL_RGB32UI​, GL_RGB32I​
64-bit GL_RGBA16F​, GL_RG32F​, GL_RGBA16UI​, GL_RG32UI​, GL_RGBA16I​, GL_RG32I​, GL_RGBA16​, GL_RGBA16_SNORM​
48-bit GL_RGB16​, GL_RGB16_SNORM​, GL_RGB16F​, GL_RGB16UI​, GL_RGB16I​
32-bit GL_RG16F​, GL_R11F_G11F_B10F​, GL_R32F​, GL_RGB10_A2UI​, GL_RGBA8UI​, GL_RG16UI​, GL_R32UI​, GL_RGBA8I​, GL_RG16I​, GL_R32I​, GL_RGB10_A2​, GL_RGBA8​, GL_RG16​, GL_RGBA8_SNORM​, GL_RG16_SNORM​, GL_SRGB8_ALPHA8​, GL_RGB9_E5​
24-bit GL_RGB8​, GL_RGB8_SNORM​, GL_SRGB8​, GL_RGB8UI​, GL_RGB8I​
16-bit GL_R16F​, GL_RG8UI​, GL_R16UI​, GL_RG8I​, GL_R16I​, GL_RG8​, GL_R16​, GL_RG8_SNORM​, GL_R16_SNORM​
8-bit GL_R8UI​, GL_R8I​, GL_R8​, GL_R8_SNORM​
GL_VIEW_CLASS_RGTC1_RED​ GL_COMPRESSED_RED_RGTC1​, GL_COMPRESSED_SIGNED_RED_RGTC1​
GL_VIEW_CLASS_RGTC2_RG​ GL_COMPRESSED_RG_RGTC2​, GL_COMPRESSED_SIGNED_RG_RGTC2​
GL_VIEW_CLASS_BPTC_UNORM​ GL_COMPRESSED_RGBA_BPTC_UNORM​, GL_COMPRESSED_SRGB_ALPHA_BPTC_UNORM​
GL_VIEW_CLASS_BPTC_FLOAT​ GL_COMPRESSED_RGB_BPTC_SIGNED_FLOAT​, GL_COMPRESSED_RGB_BPTC_UNSIGNED_FLOAT​


Additional classes for S3TC

If the original texture is an array or has multiple mipmap levels, the parameters minlayer​, numlayers​, minlevel​, and numlevels​ control which of those slices and levels are considered part of the texture. The minlevel​ and minlayer​ parameters are relative to the view of the original texture. If numlayers​ or numlevels​ extend beyond the original texture, they are clamped to the max extent of the original texture.

If the new texture's target is GL_TEXTURE_CUBE_MAP​, the clamped numlayers​ must be equal to 6. If the new texture's target is GL_TEXTURE_CUBE_MAP_ARRAY​, then numlayers​ counts layer-faces rather than layers, and the clamped numlayers​ must be a multiple of 6. If the new texture's target is GL_TEXTURE_CUBE_MAP​ or GL_TEXTURE_CUBE_MAP_ARRAY​, the width and height of the original texture's levels must be equal.

When the original texture's target is GL_TEXTURE_CUBE_MAP​, the layer parameters are interpreted in the same order as if it were a GL_TEXTURE_CUBE_MAP_ARRAY​ with 6 layer-faces.

If target​ is GL_TEXTURE_1D​, GL_TEXTURE_2D​, GL_TEXTURE_3D​, GL_TEXTURE_RECTANGLE​, or GL_TEXTURE_2D_MULTISAMPLE​, numlayers​ must equal 1.

The dimensions of the original texture must be less than or equal to the maximum supported dimensions of the new target. For example, if the original texture has a GL_TEXTURE_2D_ARRAY​ target and its width is greater than GL_MAX_CUBE_MAP_TEXTURE_SIZE​, an error will be generated if glTextureView is called to create a GL_TEXTURE_CUBE_MAP​ view.

Texture commands that take a level​ or layer​ parameter, such as glTexSubImage2D, interpret that parameter to be relative to the view of the texture. i.e. the mipmap level of the data store that would be updated via glTexSubImage2D would be the sum of level​ and the value of GL_TEXTURE_VIEW_MIN_LEVEL​.

Errors

GL_INVALID_VALUE​ is generated if minlayer​ or minlevel​ are larger than the greatest layer or level of origtexture​.

GL_INVALID_OPERATION​ is generated if target​ is not compatible with the target of origtexture​.

GL_INVALID_OPERATION​ is generated if the dimensions of origtexture​ are greater than the maximum supported dimensions for target​.

GL_INVALID_OPERATION​ is generated if internalformat​ is not compatible with the internal format of origtexture​.

GL_INVALID_OPERATION​ is generated if texture​ has already been bound or otherwise given a target.

GL_INVALID_OPERATION​ is generated if the value of GL_TEXTURE_IMMUTABLE_FORMAT​ for origtexture​ is not GL_TRUE​.

GL_INVALID_OPERATION​ is generated if origtexture​ is not the name of an existing texture object.

GL_INVALID_VALUE​ is generaged if target​ is GL_TEXTURE_CUBE_MAP​ and numlayers​ is not 6, or if target​ is GL_TEXTURE_CUBE_MAP_ARRAY​ and numlayers​ is not an integer multiple of 6.

GL_INVALID_VALUE​ is generated if target​ is GL_TEXTURE_1D​, GL_TEXTURE_2D​, GL_TEXTURE_3D​, GL_TEXTURE_RECTANGLE​, or GL_TEXTURE_2D_MULTISAMPLE​ and numlayers​ does not equal 1.

GL_INVALID_VALUE​ is generated if texture​ zero or is not the name of a texture previously returned from a successful call to glGenTextures.

Associated Gets

glTexParameter with arguments GL_TEXTURE_VIEW_MIN_LEVEL​, GL_TEXTURE_VIEW_NUM_LEVELS​, GL_TEXTURE_VIEW_MIN_LAYER​, GL_TEXTURE_VIEW_NUM_LAYERS​, or GL_TEXTURE_IMMUTABLE_LEVELS​.

See Also

glActiveTexture, glBindTexture, glTexStorage1D, glTexStorage2D, glTexStorage2DMultisample, glTexStorage3D, glTexStorage3DMultisample

View textures and S3TC compressed formats

Copyright

Copyright © 2012 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/.