Module texture

Expand description

A texture is an image loaded in video memory, which can be sampled in your shaders.

§Texture kinds

One thing that is important to understand when it comes to textures is that the way a texture is accessed (in other words, its “public API”) is disconnected from the internal representation of the data.

When it comes to accessing a texture, there are six kinds of textures:

Floating-point textures.
Integral textures (that contain signed integers).
Unsigned textures (that contain unsigned integers).
Depth textures (that contain depth information).
Stencil textures (that contain stencil information).
Depth-stencil textures (that contain at the same time depth and stencil information).

Textures have a different API depending on their kind. For example a integral texture can only be sampled in GLSL through a sampler type which is prefixed with i.

The internal format can only be chosen when the texture is created, and then can never be touched again. Integral and unsigned textures can only contain signed integers and unsigned integers.

Floating-point textures can contain either floating-points or integers. If integers are used, then the maximum value corresponds to the floating-point value 1.0 and the minimal value to 0.0. For example if a texture contains u8s and internally contains the value 128, reading from the texture will yield the value 0.5.

§Dimensions

Textures come in nine different dimensions:

Textures with one dimension.
Textures with two dimensions.
Textures with two dimensions and multisampling enabled.
Textures with three dimensions.
Cube textures, which are arrays of six two-dimensional textures corresponding to the six faces of a cube.
Arrays of one-dimensional textures.
Arrays of two-dimensional textures.
Arrays of two-dimensional textures with multisampling enabled.
Arrays of cube textures.

The difference between a 3D texture and a 2D textures array (and between a 2D texture and a 1D textures array) is that texture arrays can only be accessed by individual layers. That is, you can only access layer 0, or layer 1, or layer 2, and so on. Whereas if you use 3D textures you can access layer 0.5 for example.

All textures except depth, stencil and depth-stencil textures have mipmaps. A mipmap is a smaller version of the texture whose purpose is to be used during rendering when the texture will be small on the screen.

§Texture types in glium

In addition to the nine different dimensions types, there are nine kinds of texture formats:

The texture contains floating-point data, with either the Compressed prefix or no prefix at all.
The texture contains floating-point data in the sRGB color space, with either the Compressed prefix or not.
The texture contains signed integers, with the Integral prefix.
The texture contains unsigned integers, with the Unsigned prefix.
The texture contains depth information, with the Depth prefix.
The texture contains stencil information, with the Stencil prefix.
The texture contains depth and stencil information, with the DepthStencil prefix.

Each combination of dimensions and format corresponds to a sampler type in GLSL and in glium. For example, an IntegralTexture3d can only be bound to an isampler3D uniform in GLSL.

The difference between compressed textures and uncompressed textures is that you can’t do render-to-texture on the former.

The most common types of textures are CompressedSrgbTexture2d, SrgbTexture2d and Texture2d (the two dimensions being the width and height). These are what you will use most of the time.

§Buffer textures

A BufferTexture is a special kind of one-dimensional texture that gets its data from a buffer. Buffer textures have very limited capabilities (you can’t draw to them for example). They are an alternative to uniform buffers and SSBOs.

See the buffer_textures module for more infos.

§About sRGB

For historical reasons, the color data contained in almost all image files are not in RGB but in sRGB. sRGB colors are slightly brighter than linear RGB in order to compensate for the fact that screens darken some values that they receive.

When you load image files, you are encouraged to create sRGB textures (with SrgbTexture2d instead of Texture2d for example).

By default, glium enables the GL_FRAMEBUFFER_SRGB trigger, which expects the output of your fragment shader to be in linear RGB and then turns it into sRGB before writing in the framebuffer. Sampling from an sRGB texture will convert the texture colors from sRGB to RGB. If you create a regular RGB texture and put sRGB data in it, then the result will be too bright.

§Bindless textures

Bindless textures are a very recent feature that is supported only by recent hardware and drivers.

Without bindless textures, using a texture in a shader requires binding the texture to a specific bind point before drawing. This not only slows down rendering, but may also prevent you from grouping multiple draw calls into one because of the limitation to the number of available texture units.

Instead, bindless textures allow you to manually manipulate pointers to textures in video memory. You can use thousands of textures if you want.

Re-exports§

pub use self::bindless::ResidentTexture;
pub use self::bindless::TextureHandle;
pub use self::bindless::BindlessTexturesNotSupportedError;

Modules§

bindless: Without bindless textures, using a texture in a shader requires binding the texture to a specific bind point before drawing. This not only slows down rendering, but may also prevent you from grouping multiple draw calls into one because of the limitation to the number of available texture units.
buffer_texture: A BufferTexture is a special kind of one-dimensional texture that gets its data from a buffer. Buffer textures have very limited capabilities compared to other texture types.
compressed_cubemap: Contains the implementation of CompressedCubemap.
compressed_cubemap_array: Contains the implementation of CompressedCubemapArray.
compressed_srgb_cubemap: Contains the implementation of CompressedSrgbCubemap.
compressed_srgb_cubemap_array: Contains the implementation of CompressedSrgbCubemapArray.
compressed_srgb_texture1d: Contains the implementation of CompressedSrgbTexture1d.
compressed_srgb_texture1d_array: Contains the implementation of CompressedSrgbTexture1dArray.
compressed_srgb_texture2d: Contains the implementation of CompressedSrgbTexture2d.
compressed_srgb_texture2d_array: Contains the implementation of CompressedSrgbTexture2dArray.
compressed_srgb_texture3d: Contains the implementation of CompressedSrgbTexture3d.
compressed_texture1d: Contains the implementation of CompressedTexture1d.
compressed_texture1d_array: Contains the implementation of CompressedTexture1dArray.
compressed_texture2d: Contains the implementation of CompressedTexture2d.
compressed_texture2d_array: Contains the implementation of CompressedTexture2dArray.
compressed_texture3d: Contains the implementation of CompressedTexture3d.
cubemap: Contains the implementation of Cubemap.
cubemap_array: Contains the implementation of CubemapArray.
depth_cubemap: Contains the implementation of DepthCubemap.
depth_cubemap_array: Contains the implementation of DepthCubemapArray.
depth_stencil_cubemap: Contains the implementation of DepthStencilCubemap.
depth_stencil_cubemap_array: Contains the implementation of DepthStencilCubemapArray.
depth_stencil_texture1d: Contains the implementation of DepthStencilTexture1d.
depth_stencil_texture1d_array: Contains the implementation of DepthStencilTexture1dArray.
depth_stencil_texture2d: Contains the implementation of DepthStencilTexture2d.
depth_stencil_texture2d_array: Contains the implementation of DepthStencilTexture2dArray.
depth_stencil_texture2d_multisample: Contains the implementation of DepthStencilTexture2dMultisample.
depth_stencil_texture2d_multisample_array: Contains the implementation of DepthStencilTexture2dMultisampleArray.
depth_stencil_texture3d: Contains the implementation of DepthStencilTexture3d.
depth_texture1d: Contains the implementation of DepthTexture1d.
depth_texture1d_array: Contains the implementation of DepthTexture1dArray.
depth_texture2d: Contains the implementation of DepthTexture2d.
depth_texture2d_array: Contains the implementation of DepthTexture2dArray.
depth_texture2d_multisample: Contains the implementation of DepthTexture2dMultisample.
depth_texture2d_multisample_array: Contains the implementation of DepthTexture2dMultisampleArray.
depth_texture3d: Contains the implementation of DepthTexture3d.
integral_cubemap: Contains the implementation of IntegralCubemap.
integral_cubemap_array: Contains the implementation of IntegralCubemapArray.
integral_texture1d: Contains the implementation of IntegralTexture1d.
integral_texture1d_array: Contains the implementation of IntegralTexture1dArray.
integral_texture2d: Contains the implementation of IntegralTexture2d.
integral_texture2d_array: Contains the implementation of IntegralTexture2dArray.
integral_texture2d_multisample: Contains the implementation of IntegralTexture2dMultisample.
integral_texture2d_multisample_array: Contains the implementation of IntegralTexture2dMultisampleArray.
integral_texture3d: Contains the implementation of IntegralTexture3d.
pixel_buffer: Pixel buffers are buffers that contain two-dimensional texture data.
srgb_cubemap: Contains the implementation of SrgbCubemap.
srgb_cubemap_array: Contains the implementation of SrgbCubemapArray.
srgb_texture1d: Contains the implementation of SrgbTexture1d.
srgb_texture1d_array: Contains the implementation of SrgbTexture1dArray.
srgb_texture2d: Contains the implementation of SrgbTexture2d.
srgb_texture2d_array: Contains the implementation of SrgbTexture2dArray.
srgb_texture2d_multisample: Contains the implementation of SrgbTexture2dMultisample.
srgb_texture2d_multisample_array: Contains the implementation of SrgbTexture2dMultisampleArray.
srgb_texture3d: Contains the implementation of SrgbTexture3d.
stencil_cubemap: Contains the implementation of StencilCubemap.
stencil_cubemap_array: Contains the implementation of StencilCubemapArray.
stencil_texture1d: Contains the implementation of StencilTexture1d.
stencil_texture1d_array: Contains the implementation of StencilTexture1dArray.
stencil_texture2d: Contains the implementation of StencilTexture2d.
stencil_texture2d_array: Contains the implementation of StencilTexture2dArray.
stencil_texture2d_multisample: Contains the implementation of StencilTexture2dMultisample.
stencil_texture2d_multisample_array: Contains the implementation of StencilTexture2dMultisampleArray.
texture1d: Contains the implementation of Texture1d.
texture1d_array: Contains the implementation of Texture1dArray.
texture2d: Contains the implementation of Texture2d.
texture2d_array: Contains the implementation of Texture2dArray.
texture2d_multisample: Contains the implementation of Texture2dMultisample.
texture2d_multisample_array: Contains the implementation of Texture2dMultisampleArray.
texture3d: Contains the implementation of Texture3d.
unsigned_cubemap: Contains the implementation of UnsignedCubemap.
unsigned_cubemap_array: Contains the implementation of UnsignedCubemapArray.
unsigned_texture1d: Contains the implementation of UnsignedTexture1d.
unsigned_texture1d_array: Contains the implementation of UnsignedTexture1dArray.
unsigned_texture2d: Contains the implementation of UnsignedTexture2d.
unsigned_texture2d_array: Contains the implementation of UnsignedTexture2dArray.
unsigned_texture2d_multisample: Contains the implementation of UnsignedTexture2dMultisample.
unsigned_texture2d_multisample_array: Contains the implementation of UnsignedTexture2dMultisampleArray.
unsigned_texture3d: Contains the implementation of UnsignedTexture3d.

Structs§

CompressedCubemap: A compressed cube texture containing floating-point data.
CompressedCubemapArray: An array of compressed cube textures containing floating-point data.
CompressedSrgbCubemap: A compressed cube texture containing sRGB floating-point data.
CompressedSrgbCubemapArray: An array of compressed cube textures containing sRGB floating-point data.
CompressedSrgbTexture1d: A compressed one-dimensional texture containing sRGB floating-point data.
CompressedSrgbTexture1dArray: An array of compressed one-dimensional textures containing sRGB floating-point data.
CompressedSrgbTexture2d: A compressed two-dimensional texture containing sRGB floating-point data.
CompressedSrgbTexture2dArray: An array of compressed two-dimensional textures containing sRGB floating-point data.
CompressedSrgbTexture3d: A compressed three-dimensional texture containing sRGB floating-point data.
CompressedTexture1d: A compressed one-dimensional texture containing floating-point data.
CompressedTexture1dArray: An array of compressed one-dimensional textures containing floating-point data.
CompressedTexture2d: A compressed two-dimensional texture containing floating-point data.
CompressedTexture2dArray: An array of compressed two-dimensional textures containing floating-point data.
CompressedTexture3d: A compressed three-dimensional texture containing floating-point data.
Cubemap: A cube texture containing floating-point data.
CubemapArray: An array of cube textures containing floating-point data.
DepthCubemap: A cube texture containing depth data.
DepthCubemapArray: An array of cube textures containing depth data.
DepthStencilCubemap: A cube texture containing both depth and stencil data.
DepthStencilCubemapArray: An array of cube textures containing both depth and stencil data.
DepthStencilTexture1d: A one-dimensional texture containing both depth and stencil data.
DepthStencilTexture1dArray: An array of one-dimensional textures containing both depth and stencil data.
DepthStencilTexture2d: A two-dimensional texture containing both depth and stencil data.
DepthStencilTexture2dArray: An array of two-dimensional textures containing both depth and stencil data.
DepthStencilTexture2dMultisample: A two-dimensional texture containing both depth and stencil data.
DepthStencilTexture2dMultisampleArray: An array of two-dimensional textures containing both depth and stencil data.
DepthStencilTexture3d: A three-dimensional texture containing both depth and stencil data.
DepthTexture1d: A one-dimensional texture containing depth data.
DepthTexture1dArray: An array of one-dimensional textures containing depth data.
DepthTexture2d: A two-dimensional texture containing depth data.
DepthTexture2dArray: An array of two-dimensional textures containing depth data.
DepthTexture2dMultisample: A two-dimensional texture containing depth data.
DepthTexture2dMultisampleArray: An array of two-dimensional textures containing depth data.
DepthTexture3d: A three-dimensional texture containing depth data.
ImportParameters: Contains parameters needed to import a texture created in an external API into OpenGL. Must match with parameters used by external memory.
IntegralCubemap: A cube texture containing signed integral data.
IntegralCubemapArray: An array of cube textures containing signed integral data.
IntegralTexture1d: A one-dimensional texture containing signed integral data.
IntegralTexture1dArray: An array of one-dimensional textures containing signed integral data.
IntegralTexture2d: A two-dimensional texture containing signed integral data.
IntegralTexture2dArray: An array of two-dimensional textures containing signed integral data.
IntegralTexture2dMultisample: A two-dimensional texture containing signed integral data.
IntegralTexture2dMultisampleArray: An array of two-dimensional textures containing signed integral data.
IntegralTexture3d: A three-dimensional texture containing signed integral data.
RawImage1d: Represents raw data for a two-dimensional image.
RawImage2d: Represents raw data for a two-dimensional image.
RawImage3d: Represents raw data for a two-dimensional image.
SrgbCubemap: A cube texture containing sRGB floating-point data.
SrgbCubemapArray: An array of cube textures containing sRGB floating-point data.
SrgbTexture1d: A one-dimensional texture containing sRGB floating-point data.
SrgbTexture1dArray: An array of one-dimensional textures containing sRGB floating-point data.
SrgbTexture2d: A two-dimensional texture containing sRGB floating-point data.
SrgbTexture2dArray: An array of two-dimensional textures containing sRGB floating-point data.
SrgbTexture2dMultisample: A two-dimensional texture containing sRGB floating-point data.
SrgbTexture2dMultisampleArray: An array of two-dimensional textures containing sRGB floating-point data.
SrgbTexture3d: A three-dimensional texture containing sRGB floating-point data.
StencilCubemap: A cube texture containing stencil data.
StencilCubemapArray: An array of cube textures containing stencil data.
StencilTexture1d: A one-dimensional texture containing stencil data.
StencilTexture1dArray: An array of one-dimensional textures containing stencil data.
StencilTexture2d: A two-dimensional texture containing stencil data.
StencilTexture2dArray: An array of two-dimensional textures containing stencil data.
StencilTexture2dMultisample: A two-dimensional texture containing stencil data.
StencilTexture2dMultisampleArray: An array of two-dimensional textures containing stencil data.
Texture1d: A one-dimensional texture containing floating-point data.
Texture1dArray: An array of one-dimensional textures containing floating-point data.
Texture2d: A two-dimensional texture containing floating-point data.
Texture2dArray: An array of two-dimensional textures containing floating-point data.
Texture2dMultisample: A two-dimensional texture containing floating-point data.
Texture2dMultisampleArray: An array of two-dimensional textures containing floating-point data.
Texture3d: A three-dimensional texture containing floating-point data.
TextureAny: A texture whose type isn’t fixed at compile-time.
TextureAnyImage: Represents a specific 2D image of a texture. 1D textures are considered as having a height of 1.
TextureAnyLayer: Represents a specific layer of an array texture and 3D textures.
TextureAnyLayerMipmap: Represents a specific layer of a specific mipmap. This is the same as TextureAnyImage, except for 3D textures, cubemaps and cubemap arrays.
TextureAnyMipmap: Represents a specific mipmap of a texture.
UnsignedCubemap: A cube texture containing unsigned integral data.
UnsignedCubemapArray: An array of cube textures containing unsigned integral data.
UnsignedTexture1d: A one-dimensional texture containing unsigned integral data.
UnsignedTexture1dArray: An array of one-dimensional textures containing unsigned integral data.
UnsignedTexture2d: A two-dimensional texture containing unsigned integral data.
UnsignedTexture2dArray: An array of two-dimensional textures containing unsigned integral data.
UnsignedTexture2dMultisample: A two-dimensional texture containing unsigned integral data.
UnsignedTexture2dMultisampleArray: An array of two-dimensional textures containing unsigned integral data.
UnsignedTexture3d: A three-dimensional texture containing unsigned integral data.

Enums§

ClientFormat: List of client-side pixel formats.
CompressedFormat: List of compressed texture formats.
CompressedMipmapsOption: Describes what to do about mipmaps during compressed texture creation.
CompressedSrgbFormat: List of compressed pixel formats in the sRGB color space.
CubeLayer: Represents a layer of a cubemap.
DepthFormat: List of formats available for depth textures.
DepthStencilFormat: List of formats available for depth-stencil textures.
Dimensions: Type of a texture.
ExternalTilingMode: Describes a tiling mode used in texture storage by an external API
GetFormatError: Error that can happen when retrieving the internal format of a texture.
InternalFormat: Internal format of a texture.
InternalFormatType: Format of a component of an internal format.
MipmapsOption: Describes what to do about mipmaps during texture creation.
SrgbFormat: List of uncompressed pixel formats that contain floating-point data in the sRGB color space.
StencilFormat: List of formats available for stencil textures.
TextureCreationError: Error that can happen when creating a texture.
TextureFormat: Format of the internal representation of a texture.
TextureImportError: Error that can happen when importing a texture.
TextureKind: Represents a kind of texture.
UncompressedFloatFormat: List of uncompressed pixel formats that contain floating-point-like data.
UncompressedIntFormat: List of uncompressed pixel formats that contain signed integral data.
UncompressedUintFormat: List of uncompressed pixel formats that contain unsigned integral data.

Traits§

PixelValue: A trait that must be implemented for any type that can represent the value of a pixel.
Texture1dDataSink: Trait that describes types that can be built from one-dimensional texture data.
Texture1dDataSource: Trait that describes data for a one-dimensional texture.
Texture2dDataSink: Trait that describes types that can be built from two-dimensional texture data.
Texture2dDataSource: Trait that describes data for a two-dimensional texture.
Texture3dDataSink: Trait that describes types that can be built from one-dimensional texture data.
Texture3dDataSource: Trait that describes data for a two-dimensional texture.
ToClientFormat

Functions§

is_cubemap_arrays_supported: Returns true is cubemap arrays are supported.
is_cubemaps_supported: Returns true is cubemaps are supported.
is_texture_1d_array_supported: Returns true is one-dimensional texture arrays are supported.
is_texture_1d_supported: Returns true is one-dimensional textures are supported.
is_texture_2d_array_supported: Returns true is two-dimensional texture arrays are supported.
is_texture_2d_multisample_array_supported: Returns true is two-dimensional multisample texture arrays are supported.
is_texture_2d_multisample_supported: Returns true is two-dimensional multisample textures are supported.
is_texture_2d_supported: Returns true is two-dimensional textures are supported.
is_texture_3d_supported: Returns true is three-dimensional textures are supported.

Module textureCopy item path