Name

textureGather — gathers four texels from a texture

Declaration

gvec4 textureGather(gsampler2D  sampler,
 vec2  P,
 [int  comp]);
gvec4 textureGather(gsampler2DArray  sampler,
 vec3  P,
 [int  comp]);
gvec4 textureGather(gsamplerCube  sampler,
 vec3  P,
 [int  comp]);
gvec4 textureGather(gsamplerCubeArray  sampler,
 vec4  P,
 [int  comp]);
gvec4 textureGather(gsampler2DRect  sampler,
 vec3  P,
 [int  comp]);
vec4 textureGather(gsampler2DShadow  sampler,
 vec2  P,
 float  refZ);
vec4 textureGather(gsampler2DArrayShadow  sampler,
 vec3  P,
 float  refZ);
vec4 textureGather(gsamplerCubeShadow  sampler,
 vec3  P,
 float  refZ);
vec4 textureGather(gsamplerCubeArrayShadow  sampler,
 vec4  P,
 float  refZ);
vec4 textureGather(gsampler2DRectShadow  sampler,
 vec3  P,
 float  refZ);

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.

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.

Description

textureGather returns the value:

    vec4(Sample_i0_j1(P, base).comp,
         Sample_i1_j1(P, base).comp,
         Sample_i1_j0(P, base).comp,
         Sample_i0_j9(P, base).comp);

If specified, the value of comp must ba constant integer expression with a value of 0, 1, 2, or 3, identifying the x, y, z or w component of the four-component vector lookup result for each texel, respectively. If comp is not specified, it is treated as 0, selecting the x component of each texel to generate the result.

Version Support

FunctionVersion 1.10Version 1.20Version 1.30Version 1.40Version 1.50Version 3.30Version 4.00Version 4.10Version 4.20Version 4.30
textureGather------YYYY

See Also

texelFetch, texelFetchOffset, texture, textureGatherOffset, textureGatherOffsets, textureGrad, 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/.