TEXTUREGATHER(3G)

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_j0(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
 | OpenGL Shading Language Version
Function Name | 1.10 | 1.20 | 1.30 | 1.40 | 1.50 | 3.30 | 4.00 | 4.10 | 4.20 | 4.30 | 4.40 | 4.50
textureGather | - | - | - | - | - | - | ✔ | ✔ | ✔ | ✔ | ✔ | ✔

SEE ALSO

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

COPYRIGHT

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/.

COPYRIGHT
Copyright © 2011-2014 Khronos Group