0.9.9/api/a00323_source.html

 #pragma once
 #include "../detail/type_vec4.hpp"

 namespace glm
 {

     typedef vec<4, float, highp>        highp_vec4;

     typedef vec<4, float, mediump>      mediump_vec4;

     typedef vec<4, float, lowp>         lowp_vec4;

 }//namespace glm
glm::highp_vec4
vec< 4, float, highp > highp_vec4
4 components vector of high single-qualifier floating-point numbers.
Definition: vector_float4_precision.hpp:16

glm::lowp_vec4
vec< 4, float, lowp > lowp_vec4
4 components vector of low single-qualifier floating-point numbers.
Definition: vector_float4_precision.hpp:28

glm
Definition: common.hpp:20

glm::mediump_vec4
vec< 4, float, mediump > mediump_vec4
4 components vector of medium single-qualifier floating-point numbers.
Definition: vector_float4_precision.hpp:22