textureGatherOffsets

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Gathers four texels from a texture with an array of offsets.

Declaration[edit]

gvec4 textureGatherOffsets( gsampler2D sampler, vec2 P, ivec2 offsets[4], [int comp] );
gvec4 textureGatherOffsets( gsampler2DArray sampler, vec3 P, ivec2 offsets[4], [int comp] );
gvec4 textureGatherOffsets( gsampler2DRect sampler, vec3 P, ivec2 offsets[4], [int comp] );
vec4 textureGatherOffsets( gsampler2DShadow sampler, vec2 P, float refZ, ivec2 offsets[4] );
vec4 textureGatherOffsets( gsampler2DArrayShadow sampler, vec3 P, float refZ, ivec2 offsets[4] );
vec4 textureGatherOffsets( gsampler2DRectShadow sampler, vec3 P, float refZ, ivec2 offsets[4] );


Parameters[edit]

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.
comp - Specifies the component of the source texture that will be used to generate the resulting vector.
refZ - Specifies the reference Z value used in the comparison for shadow forms.
offsets - Specifies an array of offsets from the specified texture coordinate P from which the texels will be gathered.


Description[edit]

 textureGatherOffsets operates identically to textureGatherOffset , except that offsets is used to determine the location of the four texels to sample. Each of the four texels is obtained by applying the offset in offsets as a (u, v) coordinate offset to P , identifying the four-texel GL_LINEAR footprint, and then selecting the texel [math][/math] of that footprint. The specified values in offsets must be set with constant integral expressions.


Version Support[edit]

textureGatherOffsets 4.0+

See Also[edit]

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


Copyright[edit]

Copyright© 2011-2014 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/.