## Name

glTexStorage1D — simultaneously specify storage for all levels of a one-dimensional texture

## C Specification

`void glTexStorage1D(` | GLenum target,
| GLsizei levels,
| GLenum internalformat,
| GLsizei width`)`;

## Parameters

`target`

  Specify the target of the operation. `target` must be either `GL_TEXTURE_1D` or `GL_PROXY_TEXTURE_1D`.

`levels`

  Specify the number of texture levels.

`internalformat`

  Specifies the sized internal format to be used to store texture image data.

`width`

  Specifies the width of the texture, in texels.

## Description

`glTexStorage1D` specifies the storage requirements for all levels of a one-dimensional texture simultaneously. Once a texture is specified with this command, the format and dimensions of all levels become immutable unless it is a proxy texture. The contents of the image may still be modified, however, its storage requirements may not change. Such a texture is referred to as an immutable-format texture.

Calling `glTexStorage1D` is equivalent, assuming no errors are generated, to executing the following pseudo-code:

        for (i = 0; i < levels; i++)
        {
            glTexImage1D(target, i, internalformat, width, 0, format, type, NULL);
            width = max(1, (width / 2));
        }

Since no texture data is actually provided, the values used in the pseudo-code for `format` and `type` are irrelevant and may be considered to be any values that are legal for the chosen `internalformat` enumerant. `internalformat` must be one of the sized internal formats given in Table 1 below, one of the sized depth-component formats `GL_DEPTH_COMPONENT32F`, `GL_DEPTH_COMPONENT24`, or `GL_DEPTH_COMPONENT16`, one of the combined depth-stencil formats, `GL_DEPTH32F_STENCIL8`, or `GL_DEPTH24_STENCIL8`, or the stencil-only format, `GL_STENCIL_INDEX8`. Upon success, the value of `GL_TEXTURE_IMMUTABLE_FORMAT` becomes `GL_TRUE`. The value of `GL_TEXTURE_IMMUTABLE_FORMAT` may be discovered by calling glGetTexParameter with `pname` set to `GL_TEXTURE_IMMUTABLE_FORMAT`. No further changes to the dimensions or format of the texture object may be made. Using any command that might alter the dimensions or format of the texture object (such as glTexImage1D or another call to `glTexStorage1D`) will result in the generation of a `GL_INVALID_OPERATION` error, even if it would not, in fact, alter the dimensions or format of the object.

Table 1. Sized Internal Formats

Sized Internal Format | Base Internal Format | Red Bits | Green Bits | Blue Bits | Alpha Bits | Shared Bits
--- | --- | --- | --- | --- | --- | ---
`GL_R8` | `GL_RED` | 8 |  |  |  |
`GL_R8_SNORM` | `GL_RED` | s8 |  |  |  |
`GL_R16` | `GL_RED` | 16 |  |  |  |
`GL_R16_SNORM` | `GL_RED` | s16 |  |  |  |
`GL_RG8` | `GL_RG` | 8 | 8 |  |  |
`GL_RG8_SNORM` | `GL_RG` | s8 | s8 |  |  |
`GL_RG16` | `GL_RG` | 16 | 16 |  |  |
`GL_RG16_SNORM` | `GL_RG` | s16 | s16 |  |  |
`GL_R3_G3_B2` | `GL_RGB` | 3 | 3 | 2 |  |
`GL_RGB4` | `GL_RGB` | 4 | 4 | 4 |  |
`GL_RGB5` | `GL_RGB` | 5 | 5 | 5 |  |
`GL_RGB8` | `GL_RGB` | 8 | 8 | 8 |  |
`GL_RGB8_SNORM` | `GL_RGB` | s8 | s8 | s8 |  |
`GL_RGB10` | `GL_RGB` | 10 | 10 | 10 |  |
`GL_RGB12` | `GL_RGB` | 12 | 12 | 12 |  |
`GL_RGB16_SNORM` | `GL_RGB` | 16 | 16 | 16 |  |
`GL_RGBA2` | `GL_RGB` | 2 | 2 | 2 | 2 |
`GL_RGBA4` | `GL_RGB` | 4 | 4 | 4 | 4 |
`GL_RGB5_A1` | `GL_RGBA` | 5 | 5 | 5 | 1 |
`GL_RGBA8` | `GL_RGBA` | 8 | 8 | 8 | 8 |
`GL_RGBA8_SNORM` | `GL_RGBA` | s8 | s8 | s8 | s8 |
`GL_RGB10_A2` | `GL_RGBA` | 10 | 10 | 10 | 2 |
`GL_RGB10_A2UI` | `GL_RGBA` | ui10 | ui10 | ui10 | ui2 |
`GL_RGBA12` | `GL_RGBA` | 12 | 12 | 12 | 12 |
`GL_RGBA16` | `GL_RGBA` | 16 | 16 | 16 | 16 |
`GL_SRGB8` | `GL_RGB` | 8 | 8 | 8 |  |
`GL_SRGB8_ALPHA8` | `GL_RGBA` | 8 | 8 | 8 | 8 |
`GL_R16F` | `GL_RED` | f16 |  |  |  |
`GL_RG16F` | `GL_RG` | f16 | f16 |  |  |
`GL_RGB16F` | `GL_RGB` | f16 | f16 | f16 |  |
`GL_RGBA16F` | `GL_RGBA` | f16 | f16 | f16 | f16 |
`GL_R32F` | `GL_RED` | f32 |  |  |  |
`GL_RG32F` | `GL_RG` | f32 | f32 |  |  |
`GL_RGB32F` | `GL_RGB` | f32 | f32 | f32 |  |
`GL_RGBA32F` | `GL_RGBA` | f32 | f32 | f32 | f32 |
`GL_R11F_G11F_B10F` | `GL_RGB` | f11 | f11 | f10 |  |
`GL_RGB9_E5` | `GL_RGB` | 9 | 9 | 9 |  | 5
`GL_R8I` | `GL_RED` | i8 |  |  |  |
`GL_R8UI` | `GL_RED` | ui8 |  |  |  |
`GL_R16I` | `GL_RED` | i16 |  |  |  |
`GL_R16UI` | `GL_RED` | ui16 |  |  |  |
`GL_R32I` | `GL_RED` | i32 |  |  |  |
`GL_R32UI` | `GL_RED` | ui32 |  |  |  |
`GL_RG8I` | `GL_RG` | i8 | i8 |  |  |
`GL_RG8UI` | `GL_RG` | ui8 | ui8 |  |  |
`GL_RG16I` | `GL_RG` | i16 | i16 |  |  |
`GL_RG16UI` | `GL_RG` | ui16 | ui16 |  |  |
`GL_RG32I` | `GL_RG` | i32 | i32 |  |  |
`GL_RG32UI` | `GL_RG` | ui32 | ui32 |  |  |
`GL_RGB8I` | `GL_RGB` | i8 | i8 | i8 |  |
`GL_RGB8UI` | `GL_RGB` | ui8 | ui8 | ui8 |  |
`GL_RGB16I` | `GL_RGB` | i16 | i16 | i16 |  |
`GL_RGB16UI` | `GL_RGB` | ui16 | ui16 | ui16 |  |
`GL_RGB32I` | `GL_RGB` | i32 | i32 | i32 |  |
`GL_RGB32UI` | `GL_RGB` | ui32 | ui32 | ui32 |  |
`GL_RGBA8I` | `GL_RGBA` | i8 | i8 | i8 | i8 |
`GL_RGBA8UI` | `GL_RGBA` | ui8 | ui8 | ui8 | ui8 |
`GL_RGBA16I` | `GL_RGBA` | i16 | i16 | i16 | i16 |
`GL_RGBA16UI` | `GL_RGBA` | ui16 | ui16 | ui16 | ui16 |
`GL_RGBA32I` | `GL_RGBA` | i32 | i32 | i32 | i32 |
`GL_RGBA32UI` | `GL_RGBA` | ui32 | ui32 | ui32 | ui32 |

## Notes

`GL_STENCIL_INDEX8` is accepted for `internalformat` only if the GL version is 4.4 or higher.

## Errors

`GL_INVALID_ENUM` is generated if `internalformat` is not a valid sized internal format.

`GL_INVALID_ENUM` is generated if `target` is not `GL_TEXTURE_1D` or `GL_TEXTURE_2D`.

`GL_INVALID_VALUE` is generated if `width` or `levels` are less than 1.

`GL_INVALID_OPERATION` is generated if `levels` is greater than log 2 width + 1 .

## See Also

glTexImage1D, glTexStorage2D, glTexStorage3D.

## 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/.