Name

textureGrad — perform a texture lookup with explicit gradients

Declaration

gvec4 textureGrad(gsampler1D  sampler,
 float  P,
 float  dPdx,
 float  dPdy);
gvec4 textureGrad(gsampler2D  sampler,
 vec2  P,
 vec2  dPdx,
 vec2  dPdy);
gvec4 textureGrad(gsampler3D  sampler,
 vec3  P,
 vec3  dPdx,
 vec3  dPdy);
gvec4 textureGrad(gsamplerCube  sampler,
 vec3  P,
 vec3  dPdx,
 vec3  dPdy);
gvec4 textureGrad(gsampler2DRect  sampler,
 vec2  P,
 vec2  dPdx,
 vec2  dPdy);
float textureGrad(gsampler2DRectShadow  sampler,
 vec2  P,
 vec2  dPdx,
 vec2  dPdy);
float textureGrad(sampler1DShadow  sampler,
 vec3  P,
 float  dPdx,
 float  dPdy);
float textureGrad(sampler2DShadow  sampler,
 vec3  P,
 vec2  dPdx,
 vec2  dPdy);
gvec4 textureGrad(gsampler1DArray  sampler,
 vec2  P,
 float  dPdx,
 float  dPdy);
gvec4 textureGrad(gsampler2DArray  sampler,
 vec3  P,
 vec2  dPdx,
 vec2  dPdy);
float textureGrad(sampler1DArrayShadow  sampler,
 vec3  P,
 float  dPdx,
 float  dPdy);
gvec4 textureGrad(gsamplerCubeArray  sampler,
 vec4  P,
 vec3  dPdx,
 vec3  dPdy);

Parameters

sampler

Specifies the sampler to which the texture from which texels will be retrieved is bound.

P

Specifies the texture coordinates at which texture will be sampled.

dPdx

Specifies the partial derivative of P with respect to window x.

dPdy

Specifies the partial derivative of P with respect to window y.

Description

textureGrad performs a texture lookup at coordinate P from the texture bound to sampler with explicit texture coordinate gradiends as specified in dPdx and dPdy. Set:

δs δx = δP δx   for a 1D texture,  δP.s δx   otherwise

δs δy = δP δy   for a 1D texture,  δP.s δy   otherwise

δt δx = 0.0   for a 1D texture,  δP.t δx otherwise

δt δy = 0.0   for a 1D texture,  δP.t δy   otherwise

δr δx = 0.0   for a 1D or 2D texture,  δP.p δx   otherwise

δr δy = 0.0   for a 1D or 2D texture,  δP.p δy   otherwise

For the cube version, the partial derivatives of P are assumed to be in the coordinate system used before texture coordinates are projected onto the appropriate cube face.

Version Support

FunctionVersion 1.10Version 1.20Version 1.30Version 1.40Version 1.50Version 3.30Version 4.00Version 4.10Version 4.20Version 4.30
textureGrad--YYYYYYYY
textureGrad (gsampler2DRect{Shadow})---YYYYYYY
textureGrad (gsamplerCubeArray)------YYYY

See Also

texelFetch, texelFetchOffset, texture, textureGather, textureGatherOffset, textureGatherOffsets, textureGradOffset, textureLod, textureLodOffset, textureOffset, textureProj, textureProjGrad, textureProjGradOffset, textureProjLod, textureProjLodOffset, textureProjOffset, textureQueryLod, textureSize

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/.