Graphics.GPipe.Sampler

A sampler is a value from which filtered color samples may be taken inside a shader. A sampler is created from a texture and some sampling parameters. There also exist Shadow samplers that doesnt return a sampled color value, but instead compare a reference value to the texture value.

Sampler data types

data Sampler1D f

data Sampler1DArray f

data Sampler2D f

data Sampler2DArray f

data Sampler3D f

data SamplerCube f

data Shadow

Used instead of Format for shadow samplers. These samplers have specialized sampler values, see sample1DShadow and friends.

Creating samplers

These Shader actions all take a texture and some filtering and edge options from the shader environment, and return a sampler.

newSampler1D :: forall os f s c. ColorSampleable c => (s -> (Texture1D os (Format c), SamplerFilter c, (EdgeMode, BorderColor c))) -> Shader os f s (Sampler1D (Format c))

newSampler1DArray :: forall os f s c. ColorSampleable c => (s -> (Texture1DArray os (Format c), SamplerFilter c, (EdgeMode, BorderColor c))) -> Shader os f s (Sampler1DArray (Format c))

newSampler2D :: forall os f s c. ColorSampleable c => (s -> (Texture2D os (Format c), SamplerFilter c, (EdgeMode2, BorderColor c))) -> Shader os f s (Sampler2D (Format c))

newSampler2DArray :: forall os f s c. ColorSampleable c => (s -> (Texture2DArray os (Format c), SamplerFilter c, (EdgeMode2, BorderColor c))) -> Shader os f s (Sampler2DArray (Format c))

newSampler3D :: forall os f s c. ColorRenderable c => (s -> (Texture3D os (Format c), SamplerFilter c, (EdgeMode3, BorderColor c))) -> Shader os f s (Sampler3D (Format c))

newSamplerCube :: forall os f s c. ColorSampleable c => (s -> (TextureCube os (Format c), SamplerFilter c)) -> Shader os f s (SamplerCube (Format c))

newSampler1DShadow :: forall os f s d. DepthRenderable d => (s -> (Texture1D os (Format d), SamplerFilter d, (EdgeMode, BorderColor d), ComparisonFunction)) -> Shader os f s (Sampler1D Shadow)

newSampler1DArrayShadow :: forall os f s d. DepthRenderable d => (s -> (Texture1DArray os (Format d), SamplerFilter d, (EdgeMode, BorderColor d), ComparisonFunction)) -> Shader os f s (Sampler1DArray Shadow)

newSampler2DShadow :: forall os f s d. DepthRenderable d => (s -> (Texture2D os d, SamplerFilter (Format d), (EdgeMode2, BorderColor d), ComparisonFunction)) -> Shader os f s (Sampler2D Shadow)

newSampler2DArrayShadow :: forall os f s d. DepthRenderable d => (s -> (Texture2DArray os (Format d), SamplerFilter d, (EdgeMode2, BorderColor d), ComparisonFunction)) -> Shader os f s (Sampler2DArray Shadow)

newSamplerCubeShadow :: forall os f s d. DepthRenderable d => (s -> (TextureCube os (Format d), SamplerFilter d, ComparisonFunction)) -> Shader os f s (SamplerCube Shadow)

Types for specifying sampler filter and edge mode

data Filter

Constructors

Nearest

Linear

Instances

Enum Filter

Eq Filter

data EdgeMode

Constructors

Repeat

Mirror

ClampToEdge

ClampToBorder

Instances

Enum EdgeMode

Eq EdgeMode

type EdgeMode2 = V2 EdgeMode

type EdgeMode3 = V3 EdgeMode

type BorderColor c = Color c (ColorElement c)

type Anisotropy = Maybe Float

type MinFilter = Filter

type MagFilter = Filter

type LodFilter = Filter

data SamplerFilter c where

A GADT for sample filters, where SamplerFilter cannot be used for integer textures.

Constructors

SamplerFilter :: (ColorElement c ~ Float) => MagFilter -> MinFilter -> LodFilter -> Anisotropy -> SamplerFilter c

SamplerNearest :: SamplerFilter c

data ComparisonFunction

Constructors

Never

Less

Equal

Lequal

Greater

Notequal

Gequal

Always

Instances

Eq ComparisonFunction

Ord ComparisonFunction

Show ComparisonFunction

Sampler properties

These functions can be used to get the size of a sampler inside the shader.

sampler1DSize :: Sampler1D f -> S x Level -> S x Int

sampler1DArraySize :: Sampler1DArray f -> S x Level -> V2 (S x Int)

sampler2DSize :: Sampler2D f -> S x Level -> V2 (S x Int)

sampler2DArraySize :: Sampler2DArray f -> S x Level -> V3 (S x Int)

sampler3DSize :: Sampler3D f -> S x Level -> V3 (S x Int)

samplerCubeSize :: SamplerCube f -> S x Level -> S x Int

Sampling functions

These functions sample a sampler using its filter and edge mode. Besides the sampler and the coordinate, many additional parameters are provided to enable many different variations of sampling. In most cases when sampling in a FragmentStream, use Nothing or SampleAuto to get what you need. Float coordinates are given with components in range [0,1].

sample1D :: forall c x. ColorSampleable c => Sampler1D (Format c) -> SampleLod1 x -> SampleProj x -> SampleOffset1 x -> S x Float -> ColorSample x c

sample1DArray :: forall c x. ColorSampleable c => Sampler1DArray (Format c) -> SampleLod1 x -> SampleOffset1 x -> V2 (S x Float) -> ColorSample x c

sample2D :: forall c x. ColorSampleable c => Sampler2D (Format c) -> SampleLod2 x -> SampleProj x -> SampleOffset2 x -> V2 (S x Float) -> ColorSample x c

sample2DArray :: forall c x. ColorSampleable c => Sampler2DArray (Format c) -> SampleLod2 x -> SampleOffset2 x -> V3 (S x Float) -> ColorSample x c

sample3D :: forall c x. ColorSampleable c => Sampler3D (Format c) -> SampleLod3 x -> SampleProj x -> SampleOffset3 x -> V3 (S x Float) -> ColorSample x c

sampleCube :: forall c x. ColorSampleable c => SamplerCube (Format c) -> SampleLod3 x -> V3 (S x Float) -> ColorSample x c

The following functions sample a shadow sampler using a ReferenceValue to compare the texture values to. The returned value is a S x Float value in the range [0,1] where 0 means false, 1 means true and any value in between is a fuzzy boolean value indicating how many adjacent texels compared true and how many compared false.

sample1DShadow :: forall x. Sampler1D Shadow -> SampleLod1 x -> SampleProj x -> SampleOffset1 x -> ReferenceValue x -> S x Float -> S x Float

sample1DArrayShadow :: forall x. Sampler1DArray Shadow -> SampleLod1 x -> SampleOffset1 x -> ReferenceValue x -> V2 (S x Float) -> S x Float

sample2DShadow :: forall x. Sampler2D Shadow -> SampleLod2 x -> SampleProj x -> SampleOffset2 x -> ReferenceValue x -> V2 (S x Float) -> S x Float

sample2DArrayShadow :: forall x. Sampler2DArray Shadow -> SampleLod2' x -> SampleOffset2 x -> ReferenceValue x -> V3 (S x Float) -> S x Float

sampleCubeShadow :: forall x. SamplerCube Shadow -> SampleLod3' x -> ReferenceValue x -> V3 (S x Float) -> S x Float

The following functions retrieve a texel value from a samplers texture without using any filtering. Coordinates for these functions are integer texel indices, and not normalized coordinates.

texelFetch1D :: forall c x. ColorSampleable c => Sampler1D (Format c) -> SampleOffset1 x -> S x Level -> S x Int -> ColorSample x c

texelFetch1DArray :: forall c x. ColorSampleable c => Sampler1DArray (Format c) -> SampleOffset1 x -> S x Level -> V2 (S x Int) -> ColorSample x c

texelFetch2D :: forall c x. ColorSampleable c => Sampler2D (Format c) -> SampleOffset2 x -> S x Level -> V2 (S x Int) -> ColorSample x c

texelFetch2DArray :: forall c x. ColorSampleable c => Sampler2DArray (Format c) -> SampleOffset2 x -> S x Level -> V3 (S x Int) -> ColorSample x c

texelFetch3D :: forall c x. ColorSampleable c => Sampler3D (Format c) -> SampleOffset3 x -> S x Level -> V3 (S x Int) -> ColorSample x c

Sample parameter types

data SampleLod vx x where

A GADT to specify where the level of detail and/or partial derivates should be taken from. Some values of this GADT are restricted to only FragmentStreams.

Constructors

SampleAuto :: SampleLod v F

SampleBias :: FFloat -> SampleLod vx F

SampleLod :: S x Float -> SampleLod vx x

SampleGrad :: vx -> vx -> SampleLod vx x

type SampleLod1 x = SampleLod (S x Float) x

type SampleLod2 x = SampleLod (V2 (S x Float)) x

type SampleLod3 x = SampleLod (V3 (S x Float)) x

data SampleLod' vx x where

For some reason, OpenGl doesnt allow explicit lod to be specified for some sampler types, hence this extra GADT.

Constructors

SampleAuto' :: SampleLod' v F

SampleBias' :: FFloat -> SampleLod' vx F

SampleGrad' :: vx -> vx -> SampleLod' vx x

type SampleLod2' x = SampleLod' (V2 (S x Float)) x

type SampleLod3' x = SampleLod' (V3 (S x Float)) x

fromLod' :: SampleLod' v x -> SampleLod v x

type SampleProj x = Maybe (S x Float)

type SampleOffset1 x = Maybe Int

type SampleOffset2 x = Maybe (V2 Int)

type SampleOffset3 x = Maybe (V3 Int)

type ReferenceValue x = S x Float

type ColorSample x f = Color f (S x (ColorElement f))

The type of a color sample made by a texture t