From OpenGL Reference
Jump to navigation Jump to search

Perform a lookup of a single texel within a texture.


gvec4 texelFetch( gsampler1D sampler, int P, int lod );
gvec4 texelFetch( gsampler2D sampler, ivec2 P, int lod );
gvec4 texelFetch( gsampler3D sampler, ivec3 P, int lod );
gvec4 texelFetch( gsampler2DRect sampler, ivec2 P );
gvec4 texelFetch( gsampler1DArray sampler, ivec2 P, int lod );
gvec4 texelFetch( gsampler2DArray sampler, ivec3 P, int lod );
gvec4 texelFetch( gsamplerBuffer sampler, int P );
gvec4 texelFetch( gsampler2DMS sampler, ivec2 P, int sample );
gvec4 texelFetch( gsampler2DMSArray sampler, ivec3 P, int sample );


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.
lod - If present, specifies the level-of-detail within the texture from which the texel will be fetched.
sample - For multisampled fetches, specifies which sample within the texel from which will be returned.


texelFetch performs a lookup of a single texel from texture coordinate P in the texture bound to sampler. The array layer is specified in the last component of P for array forms. The lod parameter (if present) specifies the level-of-detail from which the texel will be fetched. The sample specifies which sample within the texel will be returned when reading from a multi-sample texure.

Version Support[edit]

texelFetch 1.3+
texelFetch (gsampler2DRect, gsamplerBuffer) 1.4+
texelFetch (gsampler2DMS, gsampler2DMSArray) 1.5+

See Also[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/.