TEXTUREGATHER(3G)               [FIXME: manual]              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 (C) 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 (C) 2011-2014 Khronos Group

[FIXME: source]                   05/21/2022                 TEXTUREGATHER(3G)