Name

textureGrad — perform a texture lookup with explicit gradients

Declaration

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);
 
float textureGrad(sampler2DShadow sampler,
 vec3 P,
 vec2 dPdx,
 vec2 dPdy);
 
float textureGrad(samplerCubeShadow sampler,
 vec4 P,
 vec3 dPdx,
 vec3 dPdy);
 
gvec4 textureGrad(gsampler2DArray sampler,
 vec3 P,
 vec2 dPdx,
 vec2 dPdy);
 
float textureGrad(gsampler2DArrayShadow sampler,
 vec4 P,
 vec2 dPdx,
 vec2 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.s δx

δs δy = δP.s δy

δt δx = δP.t δx

δt δy = δP.t δy

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

δr δy = 0.0   for a 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

OpenGL ES Shading Language Version
Function Name 1.00 3.00
textureGrad-✔

See Also

texelFetch, texelFetchOffset, texture, textureGradOffset, textureLod, textureLodOffset, textureOffset, textureProj, textureProjGrad, textureProjGradOffset, textureProjLod, textureProjLodOffset, textureProjOffset, textureSize

Copyright

Copyright © 2011-2013 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.