GLAPI/glTextureView

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glTextureView
Core in version 4.5
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_2D_MULTISAMPLE_ARRAY
GL_TEXTURE_2D_MULTISAMPLE_ARRAY GL_TEXTURE_2D_MULTISAMPLE, GL_TEXTURE_2D_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/.